(navigation image)
Home American Libraries | Canadian Libraries | Universal Library | Community Texts | Project Gutenberg | Children's Library | Biodiversity Heritage Library | Additional Collections
Search: Advanced Search
Anonymous User (login or join us)
Upload
See other formats

Full text of "Building code of the city of Boston; consisting of chapter 479 of the Acts of 1938, as amended by chapter 217 of the Acts of 1939, with the amendments by ordinance incorporated"

r€ 



ciV? 




slsJL 




Bn 



LP 




FROM THE 

ROBERT C. BILLINGS FUND 



3 1 



Digitized by the Internet Archive 

in 2010 with funding from 

Boston Public Library 



http://www.archive.org/details/buildingcodeofci1954bost 



JZ^->, J& 



*aJtZ) 



M 



BUILDING CODE 



OF THE 



CITY OF BOSTON 



Consisting of Chapter 479 of the Acts of 1938, As Amended 

by Chapter 217 of the Acts of 1939, With the 

Amendments by Ordinance Incorporated. 







CITY OF BOSTON 

ADMINISTRATIVE SERVICES DEPARTMENT 

PRINTING SECTION 

1954 





CITY OF BOSTON, 
Office of the City Clerk. 

April 1, 1955. 

I hereby certify that Chapter 479 of the Acts of 1938, 
as amended by Chapter 217 of the Acts of 1939, was 
accepted by order passed by the City Council on 
May 10, 1943, and approved by the Mayor on May 15, 
1943. 

I hereby further certify that pages 5 to 284, inclusive, 
of this volume contain a true copy of Chapter 479 of 
the Acts of 1938 as amended by Chapter 217 of the 
Acts of 1939 and by ordinances of the City of Boston 
adopted in the period from May 15, 1943, to date. 

Attest : 



W. J. Malloy, 

City Clerk. 



(2) 



CONTENTS. 



PAGE 

Part 1 — Administration 5 

2 — Fire Limits 32 

3 — Special Requirements for Group A Occupancy: Theatres . 34 

4 — Special Requirements for Group B Occupancy: Halls . . 43 

5 — Special Requirements for Group C Occupancy: Schools . 50 

6 — Special Requirements for Group D Occupancy: Hospitals 

and Detention Buildings 55 

7 — Special Requirements for Group E Occupancy: Commercial 

Buildings of Hazardous Occupancy 59 

8 — Special Requirements for Group F Occupancy: Offices and 

Commercial Buildings 62 

9 — Special Requirements for Group G Occupancy: Commercial 

Buildings of Non-Hazardous Occupancy .... 66 

10 — Special Requirements for Group H Occupancy: Unlimited 

Habitations and Large Dwellings 69 

11 — Special Requirements for Group I Occupancy: Limited 

Habitations and Small Dwellings 77 

12 — Special Requirements for Group J Occupancy: Miscellaneous 

Structures 79 

13 — Separation of Occupancies 82 

14 — Walls and Partitions 86 

15 — Protection of Vertical Openings 100 

16 — Floor Construction 104 

17 — Roof Construction and Covering 109 

18 — Exits Ill 

19 — Doors, Windows and Skylights 123 

20 — Penthouses and Roof Structures 126 

21 — Chimneys and Heating Apparatus 128 

22 — Fire-Resistive Construction 138 

23 — Live and Dead Loads 156 

24 — Masonry 163 

25 — Wood 171 

26 — Reinforced Concrete 183 

27 — Precast Gypsum Concrete 224 

28 — Steel and Iron 226 

29 — Excavations and Foundations 240 

30 — Fire Extinguishing Apparatus 253 

31 — Plumbing 261 

32 — Validity .284 

33 — War Provision \- . . .284 

Gasfitting Regulations 285 

Fire Zones 299 

Index 301 

(3) 



&fje Commontoealtf) of iflassacljusietto 



ACTS OF 1938, CHAPTER 479 



An Act for codification, revision and amendment of the laws relative 
to the construction, alteration and maintenance of buildings 
and other structures in the city of boston. 

Be it enacted by the Senate and House of Representatives in General Court 
assembled, and by the authority of the same, as follows: 

PART I. 

ADMINISTRATION. 

Section 
101— Title. 

102 — Repeals. 

103 — Pending Actions. 

104 — Other Statutes. 

105 — Effective Date. 

[105A — Amendment by Ordinance.] 

106 — Definitions. 

107 — Scope. 

108 — Maintenance. 

109 — Organization. 

1 10 — Application for Permit. 

111 — Permits. 

112 — Fees. 

113 — Inspection. 

114 — Posting Floor Loads. 

115 — Annual Report. 

116 — Powers and Duties of Building Commissioner, 

117 — Board of Appeal. 

118 — Appeals. 

1 19 — Decisions of the Board of Appeal. 

120 — Board of Examiners. 

121 — Board of Examiners of Gas Fitters. 

122 — Penalties. 

123 — Enforcement Jurisdiction. 

124 — Classification of Buildings by Types of Construction. 

125 — Types of Construction. 

126 — Type I, Fireproof Construction. 

127 — Type II, Semi=Fireproof Construction. 

128 — Type III, Heavy Timber and Masonry Construction. 

129 — Type IV, Light Wood and Masonry Construction. 

(5) 



Sees. 101-105 

Section 

130 — Type V, Metal Frame Construction. 

131 — Type VI, Wooden Frame Construction. 

132 — Occupancies Classified. 

133 — Change of Occupancy. 

134 — Multiple Occupancies. 

135 — Elevators and Escalators. 

136 — Building Height. 

Section 101. Title. — This act shall be known and may be cited as the 
Boston Building Code and is hereinafter referred to as this code. 

Sect. 102. Repeals. — Except as provided in section one hundred and 
three, the following acts and parts of acts, as severally amended, are hereby 
repealed; — chapter two hundred and sixty-five of the acts of eighteen 
hundred and ninety-seven; the two paragraphs added to section four of 
chapter three hundred and eighty-three of the acts of nineteen hundred and 
five by section one of chapter one hundred and fifty-six of the Special Acts 
of nineteen hundred and nineteen; chapter five hundred and fifty of the 
acts of nineteen hundred and seven, except section one hundred and twenty- 
eight thereof; chapter three hundred and forty-two of the acts of nineteen 
hundred and eleven; chapter seven hundred and twenty-nine of the acts of 
nineteen hundred and thirteen; chapter seven hundred and eighty-two 
of the acts of nineteen hundred and fourteen; sections one to five, inclusive, 
of chapter one hundred and sixty-three of the Special Acts of nineteen hundred 
and nineteen; chapter two hundred and seventy -eight of the acts of nineteen 
hundred and twenty-three; chapter one hundred and eighty-two of the 
acts of nineteen hundred and twenty-six; and chapter forty-two of the acts 
of nineteen hundred and twenty-seven. 

Sect. 103. Pending Actions. — All actions and proceedings, at law or in 
equity, and all prosecutions, pending on the effective date of this code, whether 
commenced for the purpose of enforcing any of the provisions of the acts, or 
parts thereof, repealed by the preceding section or brought upon any complaint 
or indictment for the violation of any of such provisions, or for the violation 
of any ordinance, rule or regulation established thereunder for the violation 
of which a penalty of a fine or imprisonment, or otherwise, is provided therein, 
may be prosecuted and enforced to the same extent as if said acts, or parts 
thereof, were still in force and effect. 

Sect. 104. Other Statutes. — All statutes applicable generally to depart- 
ments of the city of Boston, including the provisions of section five of chapter 
four hundred and eighty-six of the acts of nineteen hundred and nine, as most 
recently amended by chapter two hundred and twenty-seven of the acts of 
nineteen hundred and thirty-four, and any pertinent action taken thereunder 
whether before or after the effective date of this code, shall apply to the 
building department and to the boards established under sections one hundred 
and nine, one hundred and seventeen, one hundred and twenty and one 
hundred and twenty-one hereof. 

*Sect. 105. Effective Date. — This code shall take full effect upon its 
acceptance by vote of the city council of the city of Boston, subject to the 

(6) 



Sees. I OS- 1 06 

provisions of its charter. If an application for a permit is filed before said 
effective date, and a permit is issued thereon and the work is actually com- 
menced within ninety days after the issuance of the permit, the applicant 
notwithstanding any provision to the contrary in section one hundred and 
seven, may elect to be governed in the entire operation covered by the permit 
either by the building laws as they existed when the application was filed or 
by this code. 

[ *As amended by Ord. 1943, ch. 2 ] 
fSect. 105A. [Amendment by Ordinance.] — The city of Boston, 
for the purposes of the prevention of fire and the preservation of life, 
health and morals, or for any of such purposes, may from time to time, 
by ordinance and upon the written recommendation of the building com- 
missioner or the board of appeal, regulate the inspection, materials, con- 
struction, alteration, repair, height, area, location and use of buildings and 
other structures in said city, except such buildings or structures as are excluded 
from the operation of this code by sub -section (a) of section one hundred 
and seven, and for any or all of said purposes may from time to time, by 
ordinance upon like written recommendation, alter, amend, extend or render 
ineffective any provision or provisions of this code regulating building and 
other structures as aforesaid. 

[ fAs inserted by Stat. 1939, ch. 217 ] 
JSect. 106. Definitions. — (a) For the purposes of this code the words 
and phrases defined in this section shall be construed as so defined except 
when the context clearly indicates that another meaning is intended. 

"Abut", touch, be contiguous. A building abuts upon a street when some 
part of the building touches or extends to the line of the street. A building 
shall be construed to abut upon a street if it is nearer at any point than ten 
feet from the street or when the space between the building and the side line 
of the street is used wholly or chiefly for the purposes of a street or sidewalk. 

"Apartment", a room or suite of rooms occupied by one person or one 
family for living and sleeping purposes. 

"Apartment hotel", a building containing four or more apartments without 
kitchens, primarily for persons who have their residences therein. 

"Apartment house", a building containing four or more apartments with 
kitchens, primarily for persons who have their residences therein. 

"Approved", approved by the building commissioner of the city of 
Boston. 

"Area of a building", see "Building, area of". 

"Assembly hall", a hall or room, including the balconies thereof, if any, 
in which persons may assemble in a manner as permitted in Group B, Part 4. 

"Attic", finished or unfinished story situated within a sloping roof, the 
area of which at a height of four feet (4) above the level of its finished floor 
does not exceed two-thirds (2/3) of the area of the story immediately below it. 
There shall be only one attic in any building, and it shall be considered as a 
half story. 

"Auditorium", an assembly hall in which persons may assemble to hear or 
see concerts, plays, lectures, athletic or sports events or similar performances. 

(7) 



Sec. 106 

"Automatic sprinklers", a system of piping supplied with water under 
pressure with devices for releasing under the influence of heat and spraying 
the water on ceilings, walls and floors. 

"Balcony", within an auditorium, is a floor, inclined, stepped, or level, 
above the main floor, the open side or sides of which shall be protected by a 
rail or railings. Where a balcony of an auditorium has exits at two or more 
levels opening into separate foyers, one above another, each portion thereof 
served by such a foyer shall be considered a separate balcony for the purpose 
of this code. 

"Basement", a story of a building below the first story. 

"Building", a structure forming a shelter for persons, animals or property, 
and having a roof- The word "building" shall be construed, where the con- 
text allows, as though followed by the words "or part thereof." The word 
"building" shall not include such frame-works and tents as are customarily 
used exclusively for outdoor carnivals, lawn parties or like activities. 

"Building, area of", the maximum horizontal projected area of a building, 
above ground, within the property lines, including exterior walls one or more 
of which may be party walls and including covered porches but excluding 
terraces, steps and cornices. 

"Building, height of", in linear measure, the vertical distance of the 
highest point of the roof, excluding pent houses and roof structures, above 
the mean grade of the sidewalk at the line of the street or streets on which 
the building abuts; and, if the building does not abut on a street, above the 
mean grade of the ground around and contiguous to the building; and provided, 
further, that for the purposes of establishing said mean grade, the ground 
bounded by the lot lines and contiguous to the building and within twenty 
feet of it, shall be considered to slant toward the building not more than one 
foot upward or downward in two horizontal feet. In stories, the number of 
stories above the floor of the first story. 

"Building, pre-code", a building already erected on the effective date of 
this code, or thereafter erected, as provided in section one hundred and five, 
under permit for its construction subject to the provisions of law in effect prior 
to such effective date. 

"Building, post-code", a building erected after the effective date of this 
code and subject to the provisions thereof. 

"Bulkhead", the raised portion of a floor or roof, raised for the passage 
of persons, materials, light or air, through the side of such raised portion, or 
for other purpose. 

" Cellar ", see basement. 

"Chimney", a vertical structure of masonry with one or more flues in 
which smoke or the products of combustion are conducted upward for dis- 
posal in the open air at a height above the ground. 

"Code", "this code", the Boston Building Code, consisting of this act 
and the regulations established thereunder. 

"Commissioner", the building commissioner of the city of Boston. 

"Corridor", an enclosed passageway. 

"Dead load", the weight of materials built into the construction of a 

(8) 



Sec. 106 

building including walls, permanent partitions, floors, roofs, framing and all 
other permanent stationary construction entering into and becoming part 
of a building. 

"Department", the building department of the city of Boston. 

"Exit", a means of egress; a way out. 

"Exit from a room", a doorway or other means of egress from the room 
on the way toward an exit from the building. 

"Exit from a story", a stairway, ramp, ladder or other means of egress 
from the story on the way toward an exit from the building. 

"Exit from a building", a doorway or other means of egress from the build- 
ing opening upon a street or upon an open space with unobstructed access to 
a street. 

"Exit, path of", the continuous series of doorways, connecting rooms, 
corridors, passages, stairways, ramps and the like, which leads from any 
exit from a room through an exit from the building. 

"Family", a group of persons living together who share at least in part 
their living quarters and accommodations. 

"Fire division", a portion of a building so separated from the rest by 
separations as specified in Part 13, that it may be erected to the maximum 
height and area allowed for its principal occupancy and type of construction, 
independently of adjoining occupancies. A portion of a building separated 
from the rest by fire walls. A fire division may not be larger than a maximum 
unit of occupancy and may be further limited by the application of require- 
ments of Table A, (2), section thirteen hundred and two. 

"Fire division, area of", the maximum horizontal projected area of the 
division within the property lines including exterior walls, one or more of 
which may be party walls, and in the case of separation walls within the 
property lines to the center of the separation wall. 

"Fire door", a door of fire-resistive construction as described in Part 22. 

"Fire extinguisher", a portable device the contents of which are for ex- 
tinguishing a fire. 

"First aid hose station", a hose connection with valve in a system of piping 
adequately supplied with water, hose and nozzle for use of occupants of a 
building in extinguishing a fire. 

"Floor area", of a room, the area of the floor contained within the walls. 

"Foundation", that portion of a building or structure of which the sole 
or chief purpose or use is to transmit the weight of the building or structure to 
the earth; the support of the lowest portions of columns, walls, piers or other 
vertical members. 

"Foyer", a foyer, lobby, corridor or passage, one or more in combination, 
adjacent to the auditorium of a theatre or assembly hall at the level of the 
main floor or a balcony thereof and into which one or more exits therefrom 
open, in the path of normal egress from the building. 

"Front", a building or wall fronts upon a street when a wall of the building 
or the wall faces the street and is parallel thereto or makes an angle of less 
than forty-five degrees therewith. 

(9) 



Sec. 106 

"Fusible link", a device consisting of two pieces of brass or other suitable 
metal connected by solder or other metal fusible at a moderate temperature, 
arranged to release in the presence of fire or excessive heat; or any equivalent 
approved device. 

"Gage", for sheet metal, United States Standard Gage; for brass and 
copper tubing, Stubs Gage; for wire, Washburn & Moen or Roebling Steel 
wire gage. 

"Garage", a building or portion thereof in which is housed or stored one or 
more motor vehicles containing or using a volatile flammable fluid for fuel or 
power, or in which such motor vehicles are painted, repaired or serviced. 

"Gasfitting", the art of installing, repairing or altering pipes, fittings, 
fixtures and other apparatus for distributing gas for heat, light, power or other 
purposes; the system of pipes, fittings, fixtures and other apparatus for 
distributing gas for heat, light, power or other purposes. 

"Grade", elevation with reference to Boston city base, namely, a hori- 
zontal plane of reference established and used by the city of Boston. 

"Grade, mean", the average of the grades of mid-points of successive equal 
distances of not over ten feet measured along the line or lines along which 
the mean grade is to be determined. 

"Hotel", a building containing four or more apartments without kitchens, 
or sleeping accommodations for ten or more persons, primarily the temporary 
abode of persons who have their residences elsewhere. 

"Kitchen", a room used or adapted for cooking and containing a stove, 
range, hot-plate or other cooking apparatus, which burns coal, oil, gas or 
other fuel or is heated by electricity, except electric appliances consuming 
less than eighteen hundred watts. 

"Lintel", a beam in a masonry wall supporting the masonry above an 
opening. 

"Live load", the load or weight to be supported on floors or other portions 
of buildings incidental to their occupancy; the pressure of wind, the weight 
of snow, and all loads other than dead loads. 

"Masonry", construction of assembled units of stone, brick, concrete, 
gypsum or other similar incombustible materials separated from one another 
and held in place by mortar. 

"Masonry, dry", masonry, except that the units are not separated or held 
in place by mortar. 

"May", a term giving permission but not, except in the negative, making a 
requirement. "May" is used in this code to emphasize that specified con- 
struction is not prohibited by the code when such prohibition might other- 
wise be implied or construed; or to limit the scope of a prohibition by except- 
ing specified construction from its effect. A permission so expressed in this 
code in specific terms shall not be construed as a prohibition of other con- 
struction. "May not" is prohibitive. 

"Mezzanine floor", a floor within a story between the floor and ceiling 
thereof, having an area not over forty per cent of the area of the building at 
the level at which the mezzanine floor occurs. A floor of larger area separates 
two stories. 

(10) 



Sec. 106 

"Non-corrodible metal", a metal which, under the conditions of its use, 
may reasonably be expected, without unusual or excessive maintenance, 
to serve its purpose throughout the probable life of the structure in which it is 
used as determined by the commissioner. 

''Occupancy", use or occupancy of a building, character of use, or desig- 
nated purpose of a building or structure or portion thereof. 

"Occupancy, unit of", that portion of one building within separations 
within which the occupancy, whether of one or more tenants, falls in a single 
group and division as classified in section one hundred and thirty -two and 
Parts 3 to 12, inclusive, of this code. 

"Or", providing an alternative at the option, unless the contrary is clearly 
indicated, of the applicant for a permit. 

"Owner", the owner of e the land as recorded in the registry of deeds for 
Suffolk county, or as registered in the land court, except as otherwise provided 
in paragraph (d) of this section. 

"Partition", see Wall. 

"Passageway", a continuous way, of required width, kept clear for use 
as an exit, whether enclosed or not. 

"Pier", a vertical body of masonry used as a column, the portion of a 
masonry wall between thinner portions or between openings when the hori- 
zontal dimension parallel to the wall does not exceed four times the thickness. 

"Plan or plans". The word plan or plans shall be construed to mean 
drawing or drawings illustrating the work involved. 

"Plumbing", the art of installing, repairing or altering the pipes, fixtures 
and other apparatus for distributing the water supply and removing liquid 
and water-carried wastes; the system of pipes, fixtures and other apparatus 
installed in buildings for distributing the water supply and for the disposal 
of liquid and water-carried wastes, including valves, traps and soil, waste and 
vent pipes; provided, that nothing herein contained shall include the work 
of steamfitting. 

"Projection room", a room in a theatre or assembly hall containing a 
projector of moving pictures. 

"Remote", in reference to two or more exits, removed or distant from one 
another in such manner that a person in any place served by such exits may 
choose either of two directions in a path toward an exit and in such manner 
that a single fire could not, in its early stages, block both paths toward an 
exit. 

"Seating capacity", the number of seats within an auditorium or other 
hall when fastened to the floor; the number of persons who may be seated 
within an auditorium or hall allowing six square feet of floor area per person 
unless fixed seats are provided. 

"Separation", a system of walls, floors or other construction serving to 
separate or cut off one unit of occupancy from another. 

"Shaft", an enclosure of a vertical opening in two or more stories. 

"Smoke pipe", a flue, approximately horizontal, of metal or other material, 
in which smoke or the products of combustion are conducted from a furnace 
to a chimney or stack. 

(ID 



Sec. 106 

"Smoke stack", a vertical flue of metal or reinforced concrete, whether or 
not lined with masonry or other protective material, in which smoke, or the 
products of combustion, are conducted upward for disposal in the open air 
at a height above the ground. 

"Soil", the softer matter mostly inorganic composing part of the surface 
of the earth in distinction from the firm rock; including gravel, clay, loam 
and the like, and filling materials of similar nature. 

"Sprinklers, automatic", a system of automatic sprinklers installed in 
accordance with this code. 

"Stair, rise of", the vertical distance between successive treads or steps 
measured always from the same relative position thereon. 

"Stair, tread of", the horizontal distance from one riser to the next or from 
one nosing to the next. 

"Story", that portion of a building included between the top surface of a 
floor and the top surface of the next floor or roof above, except that a space 
used exclusively for the housing of mechanical services of the building shall 
not be considered to be a story if access to such space may be had only for 
maintenance of such services. 

"Story, first", the lowest story of which sixty-five per cent or more of the 
height is above the mean grade from which the height of the building is 
measured. 

"Structure", a combination of materials assembled at a fixed location to 
give support or shelter, such as a building, bridge, trestle, tower, frame-work, 
retaining wall, tank, tunnel, tent, stadium, reviewing stand, platform, bin, 
fence, sign, flag-pole or the like. The word "structure" shall be construed, 
where the context allows, as though followed by the words "or part thereof". 

"Unit of occupancy", see "Occupancy, unit of". 

"Unit of occupancy, area of", the maximum horizontal projected area of a 
unit of occupancy. 

"Vertical opening", an opening in a floor or roof for giving access vertically 
from the story below or above for light, ventilation, the movement of persons 
or materials or for any other purpose. 

"Wall, bearing", a wall which supports a floor, roof or other vertical load 
in addition to its own weight. 

"Wall, curtain", an exterior, non-bearing wall more than one story high 
and not supported at each floor level, which is laterally stayed by masonry 
piers or by the frame of the building. 

"Wall, enclosure", an interior wall, bearing or non-bearing, which encloses 
a stairway, elevator shaft or other vertical opening. 

"Wall, fire", a wall separating two fire divisions of a building. 

"Wall, non-bearing", a wall which supports only its own weight. 

"Wall, panel", a non-bearing exterior wall not over one story high, or 
supported at each floor level. 

"Wall, parapet", a wall or part of a wall above the roof of a building. 

"Wall, partition", an interior bearing or non-bearing wall, not over one 
story in height the chief function of which is to separate two rooms. 

"Wall, party", a wall used or adapted for use in common as a part of two 
buildings. 

(12) 



Sees. 106-107 

"Wall, retaining", a wall used to resist the lateral displacement of liquid, 
granular or other materials. 

(b) In conformity with the purposes of this code, to prescribe the minimum 
requirements for structures and the maximum utility of structures consonant 
with safety, the phrases "at least", "not less than" or "not more than" 
shall be construed to precede quantitative specifications, as determined 
by the commissioner. 

(c) Wherever in this code a public official is referred to by the title of his 
office without mention of any municipality, unless the context otherwise 
requires, such reference shall be to an official of the city of Boston. 

(d) Nothing in this code shall be held to prevent the owner of land from 
transferring to another his rights and responsibilities under this code by means 
of a lease or other suitable agreement. The commissioner may recognize 
the person to whom such a transfer by operation of law or otherwise has been 
made as the possessor of such rights and responsibilities and to such extent 
as the owner in receiving applications, issuing permits and otherwise in en- 
forcing this code. 

[ %As amended by Ord. 1943, ch. 2 and Ord. 1945, ch. 6 ] 

*Sect. 107. Scope. — (a) The provisions of this code shall apply to 
every building or structure hereafter erected in the city of Boston, except 
public highway, railroad or railway bridges or trestles, quays or wharves, 
buildings owned and occupied by the United States or the commonwealth, 
railroad structures and stations used primarily for railroad purposes, subway 
and elevated railway structures and stations used primarily for railway 
purposes, voting booths erected and maintained by the board of election 
commissioners, prefabricated metal tanks of less than five thousand gallons 
capacity and tanks exceeding ten thousand gallons capacity for liquids other 
than water, tunnels constructed and maintained by a public authority, tents 
covering an area less than one hundred square feet, fences less than six feet 
high, signs or billboards upon the ground and signs less than one square 
foot in area, upon or attached to the outside of a structure and flagpoles 
less than twenty feet in length. 

(b) The provisions of sections one hundred and eight, one hundred and 
fourteen, one hundred and sixteen, one hundred and eighteen, one hundred 
and nineteen, one hundred and twenty-two, and one hundred and twenty- 
three shall apply to pre-code buildings. 

(c) A pre-code building may be altered, repaired, enlarged, moved, or 
converted to other uses, only in conformity with the following provisions of 
this section and subject to permit as hereinafter provided. 

(d) A pre-code building which is altered or repaired within any period of 
twelve months, said alterations or repairs costing in excess of fifty per cent 
of its physical value, shall be made to conform to the requirements of this 
code for post-code buildings. A pre-code building damaged by fire or other- 
wise in excess of fifty per cent of its physical value before such damage shall 
be made to conform to such requirements, if repaired. If the cost of such 
alterations or repairs or the amount of such damage is more than twenty-five 
but not more than fifty per cent of the physical value of the building it shall 

(13) 



Sec. 107 

be made to conform to such requirements in the portions so altered or repaired 
to such extent as the commissioner may determine. For the purposes of this 
paragraph physical value shall mean the reproduction cost of the building 
less physical deterioration as determined by the building commissioner. 

(e) When occupancy of a pre-code building, or portions thereof separated 
from the remainder as required in Part 13, is so changed that the hazard is 
increased, the commissioner may require that said pre-code building or said 
portions thereof be made to conform with the provisions of this code, which 
will specifically eliminate said increased hazard. 

1. All buildings altered or repaired shall, in the opinion of the building 
commissioner, provide structural safety, adequate resistance to the spread 
of fire, and safe egress in the event of fire to the occupants. 

2. Structural safety shall be construed to mean that a building or 
parts thereof shall sustain twice the loads and stresses subjected therein or 
thereupon by actual normal use. Owners, if directed to do so by the 
building commissioner, shall demonstrate such structural safety by actual 
load tests made as directed by him. 

3. Adequate resistance to the spread of fire shall be construed to mean 
protection to adjacent properties and protection to egress enclosures 
keeping them free from fire long enough to permit the occupants to evacuate 
the building. The resistance of various materials and constructions to fire 
shall be assumed to be as stated in this code or as otherwise satisfactorily 
demonstrated to the commissioner. 

4. Safe egresses not less than two in number shall be construed to 
mean egress facilities sufficient to evacuate the building in three minutes. 
Owners of buildings shall, if directed by the building commissioner, demon- 
strate the time required to evacuate the occupants by actual test conducted 
under the direction of the commissioner. 

5. An electrical fire alarm system shall be installed, if it is necessary 
in the opinion of the commissioner to meet the above egress requirements. 

(f) A pre-code building which is enlarged in floor area or in number of 
stories shall be made to conform throughout the entire building to the require- 
ments of this code in respect to egress and fire protection. 

(g) A pre-code building to which repairs and alterations are made which 
are not covered by the preceding paragraphs of this section, may be repaired 
or altered with the same kind of materials as those of which the building is 
constructed, providing such alterations or repairs will not increase an existing 
non-conformity or hazard; but not more than twenty-five per cent of the 
roof covering of a building shall be replaced in any period of twelve months 
unless the entire roof covering is made to conform with the requirements of 
this code for post-code buildings. New roofing meeting the requirements 
of this code may be placed over existing roofing providing that it be properly 
supported and securely fastened. 

(h) A pre-code building when moved to another location shall conform 
to the requirements of this code relative to the fire limits, to location on the 
lot and to exterior walls. 

(i) Except as otherwise provided in this section, no provision of this 
code shall be held to deprive the health department, the police commissioner, 

(14) 



Sees. 107=109 

the board of street commissioners, the licensing board, the fire commissioner 

or the park department of the city of Boston either of any power or authority 

which it, he or they had on the effective date of this act or of any remedy 

then existing for the enforcement of its, his or their orders. 

(j) Provisions of this code relating to buildings shall also apply to 

structures other than buildings to such extent as they are pertinent. 

[ *As amended by Ord. 1943, ch. 2 ] 

fSect. 108. Maintenance. — All buildings or structures, and all parts 

thereof, shall be maintained in a safe condition. All devices or safeguards 

which are required by this code in a building when erected, altered or repaired, 

shall be maintained in good working order, except as otherwise provided in 

section twenty-seven A of chapter one hundred and forty-eight of the General 

Laws. Except as otherwise provided in paragraph (d) of section one hundred 

and six, the owner shall be responsible for the maintenance of all buildings 

and structures. This section shall apply to pre-code as well as to post-code 

buildings. 

[ \As amended by Ord. 1943, ch. 2 ] 

Sect. 109. Organization. — (a) There is hereby established in the city 
of Boston a department to be called the building department, which shall 
be in charge of the building commissioner. 

(b) The commissioner shall have had at least ten years' experience as an 
architect, builder or civil engineer, and shall be appointed by the mayor 
for a term of five years. He shall receive such salary as shall be fixed by 
the city council, with the approval of the mayor. 

(c) Upon the effective date of this code the building commissioner of 
the building department, as constituted immediately prior thereto, shall 
become the building commissioner of the building department established by 
paragraph (a) of this section, the members of the board of appeal, as consti- 
tuted immediately prior thereto, shall become the members of the board of 
appeal established by paragraph (a) of section one hundred and seventeen, 
the members of the board of examiners, as constituted immediately prior 
thereto, shall become the members of the board of examiners established by 
paragraph (a) of section one hundred and twenty, and the licensed master 
gasfitter member of the board of examiners of gasfitters, as constituted 
immediately prior thereto, shall become the licensed master gasfitter member 
of the board of examiners of gasfitters established by paragraph (a) of section 
one hundred and twenty-one, and each of said persons shall thereafter hold 
his respective position until the expiration of such period of time as shall be 
equal to the remainder of the term for which he was appointed, unless sooner 
removed or discharged according to law; and all of the employees of the 
building department, as constituted immediately prior thereto, who are 
subject to the civil service laws shall be reappointed to similar positions in 
the building department or the several boards established by this code with 
the same status and compensation held and received by them, respectively, 
immediately prior thereto in the building department and the several boards 
established by this code, without civil service examination or registration; 
and the said building commissioner, and all such employees upon such re- 

(15) 



Sees. 109=110 

appointment, shall retain all rights to retirement with pension that shall 
have accrued or would thereafter accrue to them, and their services shall be 
deemed to have been continuous to the same extent as if this code had not 
been passed. 

(d) The commissioner, with the approval of the mayor, may appoint 
such number of officers, inspectors, assistants and other employees as the 
city council shall from time to time determine. No person shall be appointed 
as inspector of construction who has not had at least five years' experience 
as a builder, civil engineer or architect, or as a superintendent, foreman or 
competent mechanic in charge of construction. 

(e) The commissioner may appoint as his deputy an officer or other 
employee in the department who shall, during the absence or disability of the 
commissioner, exercise all the powers of the commissioner. 

(f) No officer or employee connected with the department, except one 
whose only connection is as a member of a board, shall be financially interested 
in furnishing of labor, material or appliances for the construction, alteration 
or maintenance of a building, or in the making of plans or of specifications 
therefor, unless he is the owner of such building. No such officer or employee 
shall engage in any work which is inconsistent with his duties or with the 
interests of the department. The provisions of this paragraph shall not 
apply to the members of boards established by this code. 

(g) The commissioner shall keep a record of the business of the depart- 
ment. The records of the department shall be open to public inspection. 
The commissioner shall not, however, be required to allow inspection of the 
plans of buildings except upon request of the owner. If such request is 
made more than two months after completion of the work described in 
the plans, the commissioner shall allow such inspection only upon payment 
of such fee as the commissioner, with the approval of the mayor, may establish. 

*Sect. 110. Application for Permit. — (a) Whoever desires in the 
city of Boston to erect, enlarge, alter, substantially repair, move, demolish 
or change the occupancy of a building or structure, or to install, alter or 
substantially repair plumbing, gasfitting, fire extinguishing apparatus or 
elevators, or to install a steam boiler, furnace, heater, or other heat pro- 
ducing apparatus the installation of which is regulated by this code, or to 
install an engine or dynamo, or to cause any such work to be done, shall 
first make application to the building commissioner and obtain a permit 
therefor. 

No engine, dynamo, boiler or furnace shall be placed in any building 
without a permit from the commissioner. Every application for such permit 
shall be in writing, shall be filed with the commissioner and shall set forth 
the character of the building, the size, power and purpose of the apparatus, 
and such other information as the commissioner may require. The com- 
missioner may, after an examination of the premises described in the applica- 
tion, and after hearing the applicant and any objectors, issue a permit for 
placing a boiler or furnace on such premises, upon such conditions as he 
shall prescribe, or he may refuse such permit. If the application is for 
anything other than a boiler or furnace, the applicant shall publish in at 
least two daily newspapers published in the city of Boston, and on at least 

(16) 



Sec. 110 

three days in each, and, if so directed by the commissioner, shall also post 
conspicuously on the premises a copy of the application, and shall deliver 
copies thereof to such persons as the commissioner may designate. 

If no objection is filed with the commissioner before the expiration of 
ten days after the time of the first publication of notice, or within ten days 
of the delivery and first posting of the notice, if such delivery or posting is 
required, the commissioner shall if the arrangement, location and construction 
of the proposed apparatus is proper and in accordance with the provisions 
of this code, issue a permit for the same. If objection is filed, the application 
shall be referred to the board of appeal which may in its discretion require 
the deposit by the objector of a reasonable sum as security for the payment 
of the costs. 

After such notice as the board shall order it shall hear the same and shall 
direct the commissioner to issue a permit under such conditions as it may 
prescribe, or to withhold the same. If the permit is refused, the applicant 
and if it is granted the objectors shall pay such costs as the board may order. 

The commissioner may, from time to time, after public notice and hearing, 
prescribe the conditions on which furnaces, boilers, or other steam generators 
and hot water heaters may be maintained in buildings, and, if any person 
interested objects to such conditions and appeals from his decision establishing 
the same, the appeal shall be referred to the board of appeal, and thereupon 
said board shall prescribe the conditions. 

(b) Each application for a permit with the required fee shall be filed 
with the commissioner on a form furnished by him and shall contain a general 
description of the proposed work and its location. It shall be signed by the 
owner or his authorized agent, and before a permit is issued such application 
shall also be signed by the person who is to perform or take charge of the work 
covered by such permit. 

(c) Each application hereunder shall indicate the proposed occupancy 
of all parts of the building and of that portion of the lot, if any, not covered 
by the building, and shall contain such other information as may be required 
by the commissioner. 

(d) The commissioner may require the material facts contained in each 
such application to be certified by the applicant under oath. 

(e) When required by the commissioner, copies of plans drawn with 
sufficient clarity and detail to indicate the nature and character of the work 
shall accompany every such application, and shall be filed in duplicate with 
the commissioner. Such plans shall contain information, in the form of 
notes or otherwise, as to the quality of materials where quality is essential 
to conformity with this code. Such information shall be specific, and this 
code shall not be cited as a whole or in part, nor shall the term "legal" or its 
equivalent be used, as a substitute for specific information. 

(i) The commissioner may require details, computations, stress diagrams 
and other data necessary to describe the construction and basis of calculations. 
He may also require plans showing the location of the proposed building 
and of every existing building on the lot. He may require structural plans 
and computations to bear the signature of the architect or engineer in charge 

(17) 



Sees. 110-111 

of the structural design, and plot plans to bear the signature of an approved 
surveyor. 

(g) An application for a permit for any proposed work shall be deemed to 
have been abandoned six months after the date of filing, unless within such 
time a permit shall have been issued; provided, that for cause one or more 
extensions of time for periods of not exceeding ninety days each may be 
allowed in writing by the commissioner. 

(h) The commissioner shall examine each application for permit and the 
plans and computations filed therewith and shall ascertain by examination 
whether the construction indicated and described is in accordance with the 
requirements of this code and of all other pertinent laws or ordinances. 

(i) The commissioner may accept an application for a permit accompanied 
by plans and computations and an affidavit filed therewith by a competent 
architect or engineer to the effect that said plans and computations are in 
accordance with the requirements of this code and of all other pertinent laws 

or ordinances. 

[ *As amended by Ord. 191^3, ch. 2 ] 
fSect. 111. Permits. — (a) If the commissioner is satisfied that the 
work described in an application for permit conforms to the requirements 
of this code and other pertinent laws and ordinances, and if the person desig- 
nated by signature on the application as the person who will perform or take 
charge of the work is duly licensed, the commissioner shall issue a permit 
therefor to the applicant; provided, that if the work to be done, in the opinion 
of the commissioner, is of minor importance, and of such simple character 
that its execution by an unlicensed person will not endanger the public or any 
workman engaged thereon, the commissioner need not require the signature 
to be that of a licensed person but may issue the permit applied for after 
entering upon the application his reason for waiving such requirement. 

(b) If the application for a permit and the plans filed therewith describe 
work which does not conform to the requirements of this code or other per- 
tinent laws or ordinances, the commissioner shall not issue a permit, but shall 
return the plans to the applicant with his refusal to issue such permit. Such 
refusal when requested shall be in writing and shall contain the reasons 
therefor. 

(c) Permits for ordinary repairs, for minor alterations not involving vital 
structural changes, may be issued upon presentation of an application on a 
special form, to be furnished by the commissioner, and payment of the required 
fee. 

(d) When application for permit to erect or enlarge a building has been 
filed, and pending issuance of such permit, the commissioner may, in his 
discretion, upon payment of the required fee, issue a special permit for the 
foundations of such building. The holder of such a special permit -shall 
proceed only at his own risk and without assurance that a permit for the 
superstructure will be granted. 

(e) The commissioner shall act upon an application for a permit with 
plans as filed, or as amended, without unreasonable or unnecessary delay. 
A permit issued shall be construed to be a license to proceed with the work 
and shall not be construed as authority to violate, cancel, alter or set aside any 

(18) 



Sec. ! 1 1 

of the provisions of this code, nor shall such issuance of a permit prevent the 
commissioner from thereafter requiring correction of errors in plans or in 
construction or of violations of this code. Any permit issued shall become 
invalid unless the work authorized by it shall have been commenced within 
six months after its issuance; provided, that for cause one or more extensions 
of time, for periods not exceeding three months each, may be allowed in writing 
by the commissioner, except that in no event shall the time for commencing the 
work be extended beyond eighteen months after the issuance of the permit. 
Any permit issued may be revoked by the commissioner at any time after 
notice and hearing if there is a false statement or misrepresentation of a 
material fact in the application for the permit or in the plans or computations 
filed therewith, or if the work authorized by the permit violates any provision 
of this code or other provision of law or the permit is otherwise issued in 
error, or if in the course of the work there is any violation of any provision 
of this code or other provision of law, or if after commencement of the work 
there is unreasonable delay in completing the work, or if there is other good 
cause for revocation of the permit. 

(f) When the commissioner issues a permit he shall endorse in writing, or 
stamp, duplicate sets of plans "Approved". One set of plans so approved 
shall be retained by the commissioner and the other set shall be returned to the 
applicant, shall be kept at the site of work and shall be open to inspection at 
all reasonable times by the commissioner or his authorized representative. 

(g) An architect, engineer or builder who is preparing plans for a building 
or structure in the city of Boston may make written request of the com- 
missioner for an interpretation of this code as specifically applicable to such 
building or structure. The request shall be made on a form furnished by the 
commissioner, shall indicate the specific provision of this code as to which 
interpretation is so desired, shall be accompanied by the required fee, and 
shall contain or be accompanied by a description of the proposed work with 
plans sufficient to enable the commissioner to form an opinion. The com- 
missioner shall make reply in writing within thirty days after receipt of the 
request either that the description of the proposed work is inadequate to 
form the basis of an opinion, or that he discerns no reason under the indicated 
provision of this code for disallowing the proposed construction, or that his 
interpretation of such provision will not allow the proposed construction for 
reasons which he shall state. If the commissioner shall interpret such pro- 
vision as not allowing the proposed construction, such interpretation shall 
be deemed a disallowance thereof and any person deeming himself aggrieved 
thereby may appeal from such disallowance as provided in section one hundred 
and eighteen. 

(h) Whenever a permit is to be issued in reliance upon an affidavit as 
provided in paragraph (i) of section one hundred and ten or whenever the 
work to be covered by a permit involves construction under conditions which, 
in the opinion of the commissioner, are hazardous or complex, the commis- 
sioner shall require that the architect or engineer who signed the affidavit 
or made the plans or computations shall supervise such work, be responsible 
for its conformity with the approved plans, and forthwith upon its completion 

(19) 



Sees. 111-114 

make and file with the commissioner written affidavit that the work has been 
done in conformity with the approved plans and with the structural provisions 
of this code. In the event that such architect or engineer is not available 
a competent person whose qualifications are approved by the commissioner 
shall be employed by the owner in his stead. 

[f As amended by Ord. 1943, ch. 2 and Ord. 1953, ch. 7] 
JSect. 112. Fees. — (a) Whoever applies for a permit shall pay, at 
the time of filing his application, the fee established under authority of chapter 
two hundred and ninety-seven of the acts of nineteen hundred and thirty- 
one as amended by Chapter 173 of the acts of nineteen hundred and thirty- 
nine. 

(b) The commissioner, with the approval of the mayor, may establish 
and from time to time alter or amend fees — 

(1) For producing for inspection the plans of buildings., as provided in 
section one hundred and nine. 

(2) For issuance of a special foundation permit, as provided in para- 
graph (d) of section one hundred and eleven. 

(3) For written interpretation of this code given for the purpose of an 
appeal from a disallowance as provided in paragraph (g) of said section one 
hundred and eleven. 

(c) No fee paid in connection with an application for a permit shall be 

returned, whether or not the permit is granted. 

[ %As amended by Ord. 1943, ch. 2 ] 
Note— Chapter 297 of the Acts of 1931 was affected by Stat. 1949, 
ch. 222, which gave to the City of Boston authority to fix certain fees 
and charges. 
Sect. 113. Inspection. — (a) The commissioner shall examine each 
site, application for permit to erect or enlarge a building or structure upon 
which has been received, and shall examine all buildings, applications for 
permit to enlarge, alter, repair, move, demolish or change the occupancy of 
which has been received. He shall inspect all such buildings and structures 
from time to time during and finally upon the completion of their erection, 
enlargement, alteration, repair, moving or demolition. He shall make a 
record of every such examination and inspection and of all violations of this 
code. The publication of such records shall be privileged. 

(b) No building operation requiring a permit shall be commenced until 
the permit holder or his authorized agent shall have posted a building permit 
card in a conspicuous place protected from the weather on the front of the 
premises and in such a position as to permit the commissioner to make the 
required entries thereon respecting inspection of the work. Such card shall 
be preserved and shall remain posted until the completion of the work. 
*Sect. 114. Posting Floor Loads. — No pre-code or post-code building 
shall be occupied for any purpose which will cause the floors thereof to be 
loaded beyond their safe capacity as specified in this code; provided, that 
the commissioner may permit occupancy of a building for mercantile, com- 
mercial or industrial purposes, by a specific business, when he is satisfied 
that such safe capacity will not thereby be exceeded, even though the class of 
occupancy of such business, under this code, requires a greater load capacity. 

(20) 



Sees. 114-116 

In every such case the safe floor loads, as determined by the commissioner, 
shall be marked on metal plates of approved design which shall be supplied 
and securely affixed by the owner of the building in a conspicuous place in 
each story to which they relate. Such plates shall not be removed or defaced, 
and if lost, removed or defaced shall be replaced by such owner. No such 
owner shall place or permit to be placed, or to remain on any floor of a building 
a greater load than the safe load so determined and posted. 

[ *As amended by Ord. 1943, ch. 2 ] 
fSect. 115. Annual Report. — The commissioner shall annually, not 
later than May first, submit a report to the mayor, covering the work of the 
department during the preceding calendar year, and shall incorporate in said 
report a summary of the decisions of the board of appeal, a summary of the 
proceedings of the board of examiners and of the board of examiners of gas 
fitters, during said year, and his recommendations as to desirable amend- 
ments of this code. 

[ fAs amended by Ord. 1948, ch. 2 ] 
{Sect. 116. Powers and Duties of Building Commissioner. — (a) 
The commissioner and the health commissioner shall severally enforce the 
provisions of this code relative to his powers and duties and they may, them- 
selves or by their respective duly authorized representatives, enter any build- 
ing or premises in said city to perform any duty imposed upon them, respec- 
tively, by this code. 

(b) Upon notice from the commissioner that work on any building or 
structure is being done contrary to the provisions of this code or in a dangerous 
or unsafe manner, such work shall be immediately stopped. Such notice shall 
be in writing and given to the owner of the property, or his agent, or the 
licensed builder or mechanic doing the work, and shall state the conditions 
under which work may be resumed. 

(c) Whoever hinders or prevents, or attempts to hinder or prevent, the 
commissioner or his authorized representative from entering a building, struc- 
ture or enclosure, or part thereof, in the performance of his duty in the 
enforcement of any provision of this code shall be punished by a fine of not 
less than fifty nor more than one hundred dollars. Each day during any 
portion of which such hindering continues shall be considered a separate 
offence. 

(d) Every building of which the exits are insufficient shall be provided 
with exits satisfactory to the commissioner; and every building which is 
dangerous or unsafe shall be made safe or removed; or every such building 
shall be vacated forthwith on order of the commissioner, with the approval of 
the mayor. Such order shall be in writing and shall be addressed and de- 
livered, or mailed, postage prepaid, to the owner or tenant, if he is known and 
can be found, or otherwise by posting an attested copy of the order in a con- 
spicuous place upon an external wall of the building, and shall state the con- 
ditions under which the building may again be used or occupied. An attested 
copy so posted shall not be defaced or removed without the approval of the 
commissioner. If in the opinion of the commissioner the public safety so 
requires the commissioner, with the approval of the mayor, may at once enter 
the building or other structure which he finds unsafe or dangerous, or land 

(21) 



Sec. 116 

on which it stands, or the abutting land or buildings, with such assistance as 
he may require, and make safe or remove said unsafe or dangerous building 
or other structure and may protect the public by a proper fence or otherwise! 
as may be necessary, and for this purpose may close a public or private way. 

(e) A claim for the expense incurred by the commissioner under paragraph 
(d) shall constitute a debt due the city upon completion of the work and 
rendering to the owner of an account therefor and recoverable from the owner 
in an action of contract. Said debt, together with interest thereon at the rate 
of six per cent per annum from the date upon which said debt became due, 
shall constitute a lien upon the real estate on which the expense was incurred 
in the manner hereafter provided. Such lien shall take effect upon the filing, 
within ninety days after the debt became due, for record in the registry oi 
deeds for Suffolk county, or in the case of registered land with the assistant 
recorder for the Suffolk district, of a statement of the claim, signed by the 
commissioner, setting forth the amount claimed without interest. Such lien 
shall continue for two years from the first day of October next following the 
date of filing said statement. Such lien may be dissolved by filing for record 
in such registry of deeds or with said assistant recorder, as the case may be> 
a certificate from the collector of taxes that the debt for which such lien 
attached, together with interest and costs thereon, has been paid or legally 
abated. The collector shall have the same powers and be subject to the same 
duties with respect to such claim as in the case of the annual taxes upon real 
estate, and the provisions of law relative to the collection of such annual taxes, 
the sale of land for the non-payment thereof, and the redemption of land so 
sold shall apply. 

(i) The owner of the real estate to which a lien has attached, as provided 
in paragraph (e), within ninety days after the statement of said lien was filed 
in the registry of deeds or with said assistant recorder, as the case may be, 
may appeal to the municipal court of the city of Boston, which shall hear and 
determine after a hearing whether the amount of the claim is more than the 
amount actually expended to make safe or remove the building or structure, if 
amount is more, said court may reduce the amount of the claim to the amount 
so actually expended. 

(g) Any requirement necessary for the strength or stability of a pre-code 
or proposed structure or for the safety of the occupants thereof, not specif- 
ically covered by this code, shall be determined by the commissioner subject 
to appeal to the board of appeal. 

(h) The commissioner shall examine every building reported as dangerous 
or damaged, and shall make a written record of such examination, stating 
the nature and estimated amount of the damage, and the purpose for which 
the building was used, and in case of fire the probable origin thereof. 

(i) The commissioner and the health commissioner shall from time to 
time, as either deems proper, inspect the gas fixtures and appliances in any 
building and shall make such rules, regulations and requirements relating 
thereto as they deem safety requires, and the owner of such building shall 
comply therewith. The materials used and work performed in gas fitting 

(22) 



Sees. 116-117 

shall be subject to such regulations as shall be made by the health commis- 
sioner and the building commissioner. 

(j) The commissioner shall make and issue rules and regulations governing 
the tearing down of buildings. 

(k) The provisions of this section shall apply to pre-code as well as post- 
code buildings. 

(I) Whoever desires to substitute for the materials or methods covered 
by this code, materials or methods of construction or maintenance not covered 
thereby, shall present to the commissioner plans, methods of analysis, and 
tests or other information substantiating the analysis of the system or qual- 
ities of the material and shall make such additional tests or present satis- 
factory evidence of such tests as the commissioner may require. The costs 
of any tests required to determine acceptability of substitute materials or 
methods shall be paid by the applicant. When the strength of any construc- 
tion cannot be satisfactorily determined by the application of accepted en- 
gineering principles, its safe strength shall be determined as one sixth of the 
ultimate strength evidenced by tests of full size units or assemblies thereof 
of such construction so loaded as to produce critical stresses. Such materials 
or methods of construction shall not be used until after the commissioner 
has issued regulations fixing the practices to be followed but no such regula- 
tion shall have the effect of altering the working stresses for any material 
herein mentioned or of reducing the fire-resistive and fire-protective require- 
ments of this code. 

[ XAs amended by Ord. 1943, ck. 2 ] 
*Sect. 117. Board of Appeal. — (a) There is hereby established in 
the city of Boston a board, to be called the board of appeal, and to consist 
of five members appointed by the mayor in the following manner: — One 
member from two candidates, one to be nominated by the Boston Real Estate 
Exchange and one by the Massachusetts Real Estate Exchange; one member 
from two candidates, one to be nominated by the Boston Society of Architects 
and one by the Boston Society of Civil Engineers; one member from three 
candidates, one to be nominated by the Master Builders Association, one by 
the Building Trades Employers' Association and one by the Building Con- 
tractors Association of Massachusetts, Inc. ; one member from two candidates 
to be nominated by the Building Trades Council of Boston and Vicinity; 
and one member selected by the mayor. 

(b) Upon the expiration of the term of office of a member of said board in 
office on the effective date of this code his successor shall be appointed for the 
term of five years; and subsequent appointments to said board shall be for 
terms of five years each. Vacancies shall be filled for an unexpired term in 
the manner in which original appointments are required to be made. Each 
member of the board of appeal shall receive for every day or part thereof of 
actual service twenty dollars or such other sum as may from time to time be 
fixed by the city council with the approval of the mayor; but no member 
shall so receive in any one year more than fifteen hundred dollars or such 
other sum as may from time to time be fixed by the city council with the 
approval of the mayor. No member shall act in a case in which he has a 

(23) 



Sees. 117-119 

personal interest, and when a member is so disqualified, or absent, the remain- 
ing members shall designate a substitute. 

Note — Chapter 6 of the Ordinances of 1952 provides: "Each member of 
the board of appeal shall receive for every day or part thereof of actual 
service twenty-five dollars; but in no event shall any member of said board 
receive in any one year more than thirty-five hundred dollars in the ag- 
gregate for services rendered by him under the building code and the 
zoning law. . . . " Effective January 1, 1953. 

(c) Members of said board shall be residents of or engaged in business in 
the city of Boston. 

(d) Said board shall cause to be made a detailed record of all its pro- 
ceedings, which shall set forth the reasons for its decisions, the vote of each 
member participating therein, the absence of a member, the name of his 
substitute and any failure of a member to vote. 

(e) The board shall establish rules and regulations for its own procedure 
not inconsistent with this code. 

[* As amended by Stat. 1949, ch. 201, and Stat. 1952, ch. 212 ] 
Sect. 118. Appeals. — (a) A person whose application for a permit 
has been refused by the commissioner may appeal to said board of appeal 
within ninety days thereafter. A person who has been ordered by the com- 
missioner to incur expense may so appeal therefrom within thirty days of the 
date of such order, except that, in case of a building or structure which, in 
the opinion of the commissioner, is unsafe or dangerous, the commissioner 
may in his order limit the time for such appeal to a shorter period. A person 
aggrieved by an adverse interpretation of this code and a disallowance by the 
commissioner of proposed construction thereunder, as provided in section one 
hundred and eleven, may so appeal from such disallowance within thirty days 
after the date thereof. Appeals hereunder shall be on forms provided by the 
commissioner and shall be accompanied by such fee as may be established by 
the commissioner, with the approval of the mayor. 

(b) The commissioner may refer without fee to the board of appeal for 
its decision such cases as, in his opinion, justice requires. 

fSect. 119. Decisions of the Board of Appeal. — (a) The board 
of appeal, when so appealed to and after a hearing, may vary the application 
of any provision of this code to any particular case when in its opinion the 
enforcement thereof would do manifest injustice, provided that the decision 
of the board shall not conflict with the spirit of any provision of this code. 

(b) Every decision of said board shall be in writing, shall indicate the 
vote of each member upon the decision, and if it is to vary the application 
of any provision of this code or modify an order of the commissioner, shall 
require the assent of at least four members. Every decision shall promptly 
be filed in the office of the commissioner, and shall be open to public inspec- 
tion; a certified copy shall be sent by mail or otherwise to the appellant and 
a copy shall be kept publicly posted in the office of the commissioner for 
two weeks after filing. 

(c) A decision of said board to vary the application of any provision of 
this code or modify an order of the commissioner shall specify in what manner 

(24) 






Sees. 119-120 



such variation or modification, respectively, is made, the conditions upon 
which it is made and the reasons therefor. 

(d) Said board shall in every case reach a decision without unreasonable 
or unnecessary delay. 

(e) If the refusal, order or disallowance of the commissioner is reversed 
or modified, or the application of any provision of this code is varied by a 
decision of said board, the commissioner shall immediately take action in 
accordance with such decision; but no decision of said board shall be regarded 
as establishing a precedent or be held to amend this code or the commis- 
sioner's interpretation thereof. 

(f) A person aggrieved by a decision of said board, whether previously 
a party to the proceeding or not, or a municipal officer or board, may, within 
fifteen days after the filing of such decision in the office of the commissioner, 
bring a petition in the supreme judicial court for the county of Suffolk for a 
writ of certiorari to correct errors of law in such decision, and the provisions 
of section four of chapter two hundred and forty-nine of the General Laws 
shall, except as hereinbefore provided, apply to such petition. 

The person filing the petition shall file a bond with sufficient surety, to be 
approved by the court, for such sum as shall be fixed by the court, to indemnify 
and save harmless the person or persons in whose favor the decision was 
rendered from all damages and costs which they may sustain in case the 
decision of said board is affirmed. In case the decision of the board is affirmed 
the court, on motion, shall assess damages, and execution shall issue therefor. 
[ fAs amended by Ord. 1943, ch. 2 ] 
JSect. 120. Board of Examiners. — (a) There is hereby established 
in the City of Boston a Board of Examiners to consist of three members 
appointed by the Mayor. The Board shall consist of an engineer or architect 
with at least five years' experience in the City of Boston, a contractor or 
person well qualified in the supervision of construction work with at least 
five years' experience in the City of Boston, and a lawyer or other person 
with proper legal qualifications. Said Board shall exercise the powers and 
perform the duty herein provided. Upon the expiration of the term of office 
of a member of said Board in office on the effective date of this code, his 
successor shall be appointed for the term of three years; and subsequent 
appointments to said Board shall be for terms of three years each. Vacancies 
shall be filled by appointments by the Mayor for the remainder of the un- 
expired term. Each member of the board of examiners shall receive for 
every day or part thereof of actual service ten dollars or such other sum as 
may from time to time be fixed by the city council with the approval of the 
mayor; but no member shall so receive in any one year more than one thousand 
dollars or such other sum as may from time to time be fixed by the city 
council with the approval of the mayor. 

Note — Section 6 of the Ordinances of 1952 provides: "Each member of 
the board of examiners, and the appointive member of the board of ex- 
aminers of gasfitters, shall receive for every day or part thereof of actual 
service fifteen dollars, bat in no event more than fifteen hundred dollars 
in any one year. " 

(25) 



Sec. 120 

(b) Said board shall hold examinations, under rules and regulations 
adopted by it, of persons desiring to be registered as qualified to have charge 
or control of the construction, alteration, removal or tearing down of build- 
ings or structures, or the installation or repair of elevators and escalators. 
Due notice of the time and place for such examinations shall be posted in 
the office of the building department and published in the City Record. 

Note — Stat. 1945, Chap. 626, provides that the licensing of elevator and 
escalator mechanics shall be under the jurisdiction of the State Depart- 
ment of Public Safety. 

(c) Said board shall establish various classes of persons to be registered, 
shall determine the qualifications required for each class, and after examina- 
tion shall register in each class the persons found to possess the requisite 
qualifications therefor. The name and address of each person so found to 
be qualified, with the designation of the class in which he is registered, shall 
thereupon be certified by said board to the commissioner, who shall make 
a record thereof, which shall be open to public inspection. 

Cd) Except as otherwise provided in section one hundred and eleven, 
all work of erecting, enlarging, altering, repairing, moving and demolishing 
of buildings or structures and installing and repairing of elevators and es- 
calators in the city of Boston shall be under the charge, control and personal 
supervision of a licensed builder or mechanic, qualified by education, training 
and experience for the performance of that duty in a manner which shall 
preserve the public safety and conform to this code and all other pertinent 
laws and ordinances. 

(e) Any person who shall by affidavit, together with such other evidence 
as may be required by said board, show to it that he has had charge or control 
of such work in the class in which he applies to be registered, and shall satisfy 
the board that he is qualified by education, training and experience to have 
charge or control of such work, may, without other examination, be registered 
in such class and be certified to the commissioner as a person qualified within 
such class. 

(f) Said board, upon payment of the required fee, shall issue a license 
to each person so certified by it to the commissioner. Each license shall 
expire one year from the date of its issuance. Said board shall renew a 
license, upon the expiration thereof and upon payment of the required fee 
therefor, for the further period of one year from the date of renewal. The 
fees to be paid to said board for such licenses and renewals shall be as pro- 
vided in chapter two hundred and ninety-seven of the acts of nineteen hun- 
dred and thirty-one, as amended by Chapter 173 of the acts of nineteen 
hundred and thirty -nine. 

(g) Any person who is duly licensed as aforesaid shall be entitled to 
have charge or control of any work described in this section, in the class in 
which he is registered, until his license is revoked or suspended by the com- 
missioner, upon the order of said board. No such license shall be revoked 
or suspended except upon proof, satisfactory to said board, or specific charges, 
filed with said board by the commissioner or other person, that the licensee 
has been careless or negligent in the performance of his duty in connection 
with work under his charge or control, or has caused or permitted a violation 

(2G) 



Sees. 120=121 

of this code in connection therewith, or that this code has been violated in 
connection with such work and that the licensee, being in charge of such 
work, knew, or, in the exercise of due diligence, should have known, of such 
violation. Upon learning of such carelessness, neglect of duty or violation 
of this code, the commissioner shall file charges with said board and prosecute 
them. Upon the filing thereof by the commissioner or other person, said 
board shall give to the licensee notice of a hearing thereon, which hearing 
shall be held by said board not less than seven days after date of said notice. 
Such notice shall be served upon the licensee either by service in hand or by 
registered mail, shall state the time and, place of the hearing and shall con- 
tain a copy of the charges. At such hearing the licensee may be represented 
by counsel, and the commissioner may be assisted by a representative of the 
law department of the city. 

(h) If, for any cause, a person licensed as herein provided shall cease to 
have charge or control of work described in this section before such work is 
finished, the work shall stop until another person duly licensed for the doing 
of such work has been placed in charge thereof. 

(i) Whoever violates any provision of this section shall be punished by a 
fine of not more than fifty dollars. 

[ tAs amended by Stat. 1952, ch. 212 and Ord. 1943, ch. 2 ] 
*Sect. 121. Board of Examiners of Qasfitters. — (a) There is hereby 
established in the city of Boston a board of examiners of gasfitters, to consist 
of three members, who shall be the building commissioner, the health com- 
missioner and a licensed master gasfitter. The member of the board of 
examiners of gasfitters who is a licensed master gasfitter shall be appointed 
annually by the mayor for a term ending on the first day of May of the year 
next ensuing; and he shall receive for every day or part thereof of actual 
service ten dollars or such other sum as may from time to time be fixed by 
the city council with the approval of the mayor. He shall have been con- 
tinuously engaged in business as a master gasfitter during the five years 
next preceding his appointment. 

Note — See note under Sect. 120, par. (a). 

(b) Said board shall hold examinations, under rules and regulations 
adopted by it, of persons desiring to engage in business as master gasfitters 
or to work as journeyman gasfitters. Due notice of the time and place for 
such examinations shall be posted in the office of the department and published 
in the City Record. 

(c) Said board shall determine the qualifications required for registration 
as master gasfitter and as journeyman gasfitter, and after examination shall 
register as such the persons found to possess the requisite qualifications. 
Said board shall, without re-examination, register as qualified master gas- 
fitters or journeyman gasfitters, as the case may be, persons desiring so to be 
registered who were so licensed before the effective date of this code. The 
name and address of each person so found to be qualified and registered, 
and the place of business of each person qualified as a master gasfitter, shall 
thereupon be certified by said board to the commissioner who shall, upon 
payment of the required fee, issue to each person so registered and certified a 

(27) 



Sees. 121=122 

license to engage in business as a master gasfitter or to work as a journeyman 
gasfitter, as the case may be. 

(d) Every original license issued under this section shall take effect upon 
its issuance and shall expire on such date, not later than one year after its 
effective date, as said board shall determine. Upon the expiration of any 
license issued under this section, the commissioner shall, upon payment of 
the required fee, renew the same except that, unless otherwise ordered by said 
board, he shall not renew the license of any person whose registration has been 
cancelled or whose license has been revoked or suspended. Every renewal 
license issued under this section shall take effect on such date, not later than 
one month after its issuance, and expire on such date, not later than one year 
after its effective date, as said board shall from time to time determine. The 
registration of any person whose license has not been renewed within one year 
after its expiration shall be cancelled. 

(e) The fee for issuance or renewal of a master gasfitter's license shall be 
two dollars and that for issuance or renewal of a journeyman gasfitter's 
license shall be fifty cents; provided, that such fees may be changed from 
time to time by the building commissioner, with the approval of the mayor. 

(f) Except as otherwise provided in this section all gas fitting in buildings 
shall be done by licensed master gasfitters, either themselves or through 
licensed journeymen gasfitters employed by them. A firm or corporation 
employing journeymen gasfitters shall be deemed to be licensed for the 
purpose of this section if a member of the firm or an officer of the corporation 
is duly licensed as a master gasfitter. A permit for gas fitting in buildings 
shall be issued only to licensed master gasfitters. 

(g) No person shall connect, disconnect or remove a gas meter, except 
the duly authorized representative of the gas company owning such meter. 
Nothing in this section shall be construed to affect the operations of a gas 
company upon its own premises or upon its mains and service pipes. 

(h) Whoever violates any provision of this section shall be punished 
by a fine of not more than one hundred dollars, and, in addition, if the offender 
is licensed under this section, his license shall be revoked or suspended by 
the commissioner, when so ordered by said board after a hearing. 
[*As amended by Stat. 1952, ch. 212, Stat. 1955, ch. 4, and Ord. 1943, ch. 2] 

Sect. 122. Penalties. — (a) A building or structure which is erected 
or maintained in violation of any provision of this code shall be deemed a 
common nuisance without other proof thereof than proof of the unlawful 
construction or maintenance, and the commissioner may abate and remove 
it in the same manner in which boards of health may remove nuisances 
under sections one hundred and twenty-three to one hundred and twenty- 
five, inclusive, of chapter one hundred and eleven of the General Laws. 

(b) Except as otherwise provided in this code, whoever violates any 
provision thereof, or whoever builds, alters, or maintains a structure or a 
part thereof in violation of any provision thereof, shall be punished by a 
fine of not exceeding five hundred dollars. Each day during any portion 
of which such violation is allowed to continue, or is permitted by the owner, 
shall be considered a separate offence. 

(28) 



Sees. 123=124 

Section 123. Enforcement Jurisdiction. — (a) Any court having 
jurisdiction in equity, or any justice thereof, may, upon the application of the 
city by its attorney — 

(1) Restrain the construction, alteration, repair, maintenance, use or 
occupation of any building or structure constructed, maintained, used or 
occupied in violation of any provision of this code, and order its removal 
or abatement as a nuisance; 

(2) Restrain the further construction, alteration, repair, maintenance, 
use or occupation of any building or structure which is unsafe or dangerous ; 

(3) Restrain the unlawful construction, alteration, repair, maintenance, 
use or occupation of any building or structure; 

(4) Compel compliance with the provisions of this code; 

(5) Order the removal by the owner of a building or structure unlaw- 
fully existing and authorize the commissioner, with the written approval 
of the mayor, in default of such removal by the owner, to remove it at the 
owner's expense. 

(b) The municipal court of the city of Boston, concurrently with the 
superior court, shall have jurisdiction throughout the city of prosecutions 
and proceedings at law under the provisions of this code, and all other pertinent 
laws and ordinances. 

(c) Upon the entry of any case brought under any provision of this code 
the court shall, at the request of either party, advance the case, so that it 
may be heard and determined with as little delay as possible. 

*Sect. 124. Classification of Buildings by Types of Construction.— 

(a) Buildings shall be classified by types of construction representing 
varying degrees of resistance to fire. All buildings required to be of a given 
type of construction shall conform to the minimum requirements of this code 
for that type, but materials and combinations of materials which offer greater 
resistance to fire than those specified for minimum requirements may be 
used. Every building shall be classified as of the most fire-resistive type 
all of the minimum requirements of which it fully meets. No building or 
portion thereof shall be required to conform to a type of construction more 
fire-resistive than that specified for its occupancy and size, or for its location 
in the fire zones, in this code. 

(b) When two or more types of construction occur in the same building 
and are separated as provided in this code, each portion so separated may be 
classified as of the type of construction to which it conforms; otherwise the 
entire building shall be classified as of the least fire-resistive type of con- 
struction used, and shall be subject to the restrictions of this code imposed 
upon that type. 

(c) A pre-code building which cannot be definitely classified as one of 
the types defined in sections one hundred and twenty-five to one hundred and 
thirty-one, inclusive, shall be deemed for the purpose of this code to belong 
to the less fire-resistive of the two types to which it most nearly conforms. 

[ *As amended by Ord. 1943, ch. 2 ] 
(29) 



Sees. 125=132 

Sect. 125. Types of Construction. — All buildings shall be classified 
for the purpose of this code in the following types of construction: — 
Type I. Fireproof. 
Type II. Semi-Fireproof. 
Type III. Heavy Timber and Masonry. 
Type IV. Light Wood and Masonry. 
Type V. Metal Frame. 
Type VI. Wooden Frame. 

Sect. 126. Type I, Fireproof Construction. — Buildings of Type I 
construction shall be of incombustible materials in all structural parts; their 
exterior bearing walls and frames shall be of four-hour fire-resistive construc- 
tion and their floors and roofs shall be of three-hour fire resistive construction 
and shall furnish protection of three-hour fire-resistive rating against the 
spread of fire. 

Sect. 127. Type II, Semi=Fireproof Construction. — Buildings of 
Type II construction shall be of incombustible materials in all structural 
parts; their exterior bearing walls shall be of four-hour fire-resistive con- 
struction, their columns and frames shall be of two-hour fire-resistive con- 
struction and their floors and roofs shall be of one-hour fire-resistive construc- 
tion and shall furnish protection of one-hour fire-resistive rating against the 
spread of fire. 

Sect. 128. Type III, Heavy Timber and Masonry Construction. — 
Buildings of Type III shall have exterior bearing walls of masonry or other 
construction of incombustible materials of four-hour fire-resistive construc- 
tion, and their frames, floors and roofs shall be of heavy timber construction 
without concealed air spaces. 

Sect. 129. Type IV, Light Wood and Masonry Construction. — 
Buildings of Type IV shall have exterior bearing walls of masonry or other 
construction of incombustible materials of four-hour fire-resistive construction 
and their frames, floors and roofs may be of wood. 

Sect. 130. Type V, Metal Frame Construction. — Buildings of Type 
V shall have walls, frames, floors and roofs of metal or other incombustible 
materials which may be without protection against fire. 

Sect. 131. Type VI, Wooden Frame Construction. — Buildings of 
Type VI may have walls, frames, floors and roofs of wood. 

*Sect. 132. Occupancies classified. — (a) Every building, whether 
pre-code or post-code, shall, for the purpose of this code, be classified according 
to its principal occupancy, as follows:— 

Group A. Theatres. 

Group B. Halls. 

Group C. Schools. 

Group D. Hospitals and detention buildings. 

Group E. Commercial buildings of hazardous occupancy. 

Group F. Offices and commercial buildings. 

Group G. Commercial buildings of non-hazardous occupancy. 

Group H. Unlimited habitations and large dwellings. 

Group I. Limited habitations and small dwellings. 

Group J. Miscellaneous structures. 

(30) 



Sees. 132=136 

(b) An occupancy not mentioned specifically in this section or in the 
definitions of groups and sub-divisions of groups contained in Parts 3 to 12, 
inclusive, of this code, or about which there is any question, shall be classified 
by the commissioner and included in the group which it most nearly resembles, 
as regards fire hazard and danger to the lives of persons. 
[ *As amended by Ord. 1948, ch. 2 ] 
fSect. 133. Change of Occupancy. — The occupancy of a building shall 
not be changed unless such building conforms or is made to conform with 
the requirements of this code for the group in which it is to be classified, 
except that the occupancy of a pre-code building may be changed as provided 
in section one hundred and seven. 

[ f As amended by Ord. 1943, ch. 2] 

Sect. 134. Multiple Occupancies. — When a building contains two or 
more units of occupancy, whether of the same or of different occupancy 
classifications, the separations between such units and the aggregate area of 
such units within the building shall be as provided in this code. 

Sect. 135. Elevators and Escalators. — No elevator or escalator shal] 
be installed in a building or structure except under the provisions of sections 
sixty-two to seventy-one, inclusive, of chapter one hundred and forty-three 
of the General Laws and the regulations issued thereunder, and in conformity 
with section one hundred and twenty of this code. 

Sect. 136. Building Height. — (a) No building or structure shall be 
so erected or altered that any part thereof shall be higher above the ground 
than two and one half times the shortest horizontal distance of that part from 
the further side of the street upon which it fronts ; provided, that, in case of a 
building at the intersection of two streets, within one hundred and fifty feet 
measured along the streets from the intersection of the nearer side lines thereof, 
the width of each street shall for the purpose of this section be taken as the 
width of the wider street. 

(b) No building or structure shall be erected or altered to a greater height 
measured to the highest point of the roof thereof than one hundred and fifty- 
five feet except as provided in this paragraph. If a building or structure shall 
be erected or altered to a greater height than one hundred and fifty-five feet 
every part of such building shall not be higher above the ground than one 
hundred and twenty-five feet plus two and one half times the shortest hori- 
zontal distance of that part from the nearest lot or street line. No building 
shall be erected or enlarged to contain a volume above the grade of the ground 
greater than the buildable area of the lot multiplied by one hundred and 
fifty-five feet. 

(c) In determining the height of any part of a building for the purposes 
of this section, the grade of the ground from which measurement shall be made 
shall be that from which the height of the building is measured as defined in 
section one hundred and six. Flag poles and weather vanes shall not be 
considered a part of a building for the purposes of this section. 



(31) 



Sees. 20N203 



PART 2. 
FIRE LIMITS. 

Section 

201 — Fire Limits. 

202 — Boundaries. 

203 — Construction within the Fire Zones. 

Section 201. Fire Limits. — For the purposes of this code there shall 
be established in the city of Boston two fire districts or zones within which 
building construction shall be limited as provided in this part of the code. 
Outside of the boundaries of the zones no limitation is placed by this part 
of the code upon the construction of buildings. 

Sect. 202. Boundaries. — (a) The boundaries of the first fire zone 
shall be the boundaries of the building limits as they existed prior to the 
twenty-second day of September in the year nineteen hundred and thirteen. 

(b) The boundaries of the second fire zone shall be the boundaries of 
the building limits as they were established on and after the twenty-second 
day of September in the year nineteen hundred and thirteen. 

(c) The city council of the city of Boston may by ordinance from time 
to time extend either fire zone and re-establish its boundaries. 

*Sect. 203. Construction within the Fire Zones. — (a) Buildings 
hereafter erected in the first or second fire zone shall be of Type I, Type II, 
Type III or Type IV construction except as hereinafter provided. 

(b) The limitations of this section shall not apply to buildings not over 
twenty-seven feet high on wharves and buildings for the storage and handling 
of coal or grain in bulk, of Type V or Type VI construction, in either fire 
zone, if the exterior thereof is covered with slate, tin, sheet metal or other 
equally fire-resistive construction, erected with the approval of the com- 
missioner and subject to such conditions as he may in each case specify. 

(c) Temporary structures to be used in connection with construction 
work and temporary reviewing stands, frame-works and tents, as are cus- 
tomarily used exclusively for outdoor carnivals, lawn parties or like activities, 
may be erected in either fire zone and of any type of construction, subject to 
the approval of the commissioner, and to such conditions and for such time 
as he may in each case specify. 

(d) Buildings of Type VI construction for dwellings for one or two families 
may be erected or enlarged in the second fire zone where the area of each does 
not exceed sixty per cent of the area of the lot on which it is located and the 
roof is pitched at not less than thirty degrees with the horizontal. 

(e) Buildings of Type V construction may be erected or enlarged for use 
as garages in the second fire zone providing they are equipped with fire win- 
dows and are not within two feet of a lot line or within five feet of a building 
of Type VI construction and the height does not exceed one story and the 
area six hundred square feet and the capacity two cars. 

(32) 



Sec. 203 

(f) Buildings of Type V construction for other occupancies may be erected 
in the second fire zone providing the location and the occupancy are approved 
by the building commissioner. 

(g) Buildings in the first or second fire zone erected, enlarged or con- 
verted to use as a garage for more than four cars shall be of Type I or Type II 
construction and if such garage be more than one story in height it shall be 
of Type I construction. 

(h) Every building in Group C in the first or second fire zone shall be of 
Type I or Type II construction. 

[ *As amended by Ord. 1945, ch. 6 ] 



(33) 



Sees. 30U303 



PART 3. 

SPECIAL REQUIREMENTS FOR GROUP A OCCUPANCY: 

THEATRES. 

Section 

301 — Group A Occupancy: Type, Height, Area. 

302 — Separation of Occupancies. 

303 — Exterior Wails. 

304 — Enclosure of Vertical Openings. 

305 — Exits and Entrances. 

306 — Aisles and Seating. 

307 — Exit Lights. 

308 — Light and Ventilation. 

309 — Stage Ventilators, Group A Occupancy. 

310 — Proscenium. 

311 — Stage Construction. 

312 — Dressing Rooms and Workshops. 

313 — Fire=Extinguishing Apparatus. 

314 — Projection Room. 

Section 301. Group A Occupancy: Type, Height, Area. — (a) 

Group A shall include every building containing an auditorium and a per- 
manent stage equipped with a gridiron or other means of hanging scenery, 
and primarily adapted for the giving of plays, operas or similar forms of 
entertainment. 

(b) Buildings or parts of buildings, classified for occupancy in Group A, 
shall be of Type I construction, except that portion of the stage which, under 
the provisions of section three hundred and eleven, may be of wood or un- 
protected metal, and they shall not hereby be limited as to seating capacity, 
area or height. 

Sect. 302. Separation of Occupancies. — Portions of a building of 
Group A occupancy may be used for purposes other than the giving of plays, 
operas and the like, but the parts given to such other occupancies shall be 
separated from that devoted to Group A occupancy by separations specified 
in Part 13. 

*Sect. 303. Exterior Walls. — (a) Exterior walls or parts of walls, 
except where fronting on a street, which are less than five feet from a property 
line, shall be without openings, except that openings in such walls at the ends 
of courts shall be allowed when protected by fire windows or Class B fire 
doors. Openings in such walls or parts of walls which are five feet or more 
but less than ten feet from a property line shall be protected by fire windows 
or Class B fire doors. 

(b) In an exterior wall, every opening which faces, at a distance of less 
than twenty feet, the further side of a street or a combustible wall or roof 
or an unprotected opening in a wall or roof of another building on the same 
lot, shall be protected by fire windows or Class B fire doors. 

(34) 



Sees. 303=305 

(c) The commissioner may waive the requirements of this section, for 
protection or prohibition of openings in walls, temporarily pending construc- 
tion on an adjoining lot or across a street, provided the owner agrees in a 
writing recorded in the registry of deeds for Suffolk county to comply with the 
said requirements on demand of the commissioner. 

[ *As amended by Ord. 1943, ch. 2 ] 

Sect. 304. Enclosure of Vertical Openings. — (a) Stair or ramp 
exits from only the first or lower balcony need not be enclosed. Stair or ramp 
exits from smoking rooms, lounges or other public rooms in the basement 
shall be enclosed in the basement or first story, and the doors shall be self- 
closing but need not be fire doors. Other stairways and ramps which pierce 
only one floor shall be enclosed in the story above or below but such stairways 
or ramps which serve as required exits from one story shall be enclosed in the 
other story. Stairways or ramps serving dressing rooms need not be enclosed 
above the stage or first floor if separated from the stage by a two-hour separa- 
tion. Other stairways and ramps shall be enclosed in all stories in which they 
occur. There shall be no openings in stair or ramp enclosures except entrance 
and exit doorways and the openings required for ventilation. 

(b) Vertical openings for elevators serving dressing rooms need not be 
enclosed above the stage or first floor if they are separated from the stage by a 
two-hour separation. Vertical openings for elevators serving the gridiron 
and fly galleries need not be enclosed above the stage level. All other vertical 
openings for elevators and vertical openings for ventilation or other purposes, 
except as otherwise specified in this section, shall be enclosed. 

fSect. 305. Exits and Entrances. — (a) Group A buildings shall be 
so located that the main entrances shall open directly from a public street or 
streets not less than thirty feet wide. The main entrance or entrances, which 
may also serve as exits, shall have in the aggregate twenty inches of un- 
obstructed width for each one hundred persons to and including one thou- 
sand persons, with an additional ten inches for each additional one hundred 
persons to and including one thousand additional persons, and an additional 
five inches for each additional one hundred persons over two thousand, all 
based on the total seating capacity of the building served by said entrances. 
No main entrance shall be less than fifteen feet in clear width between walls 
or in aggregate width of doorways and of passageways but such width shall 
not be required to exceed forty feet in width. Doorways and passageways in 
such entrances shall be not less than five feet in clear width. 

(b) Adjacent to the main floor and each balcony of the auditorium and 
between the auditorium and the main entrance, in the path of normal entrance 
and egress, there shall be a foyer consisting of a lobby, corridor or passageway, 
one or more, the aggregate floor area of which shall be at least equal to one 
square foot for each seat in such division of the auditorium. 

(c) There shall be at least two remote exits from the main floor and from 
each balcony of the auditorium. One of these exits from the main floor and 
one from each balcony shall open into the foyer required therefor in this 
section. Both such exits may open into the required foyer if it has two remote 
exits. 

(35) 



Sec. 305 

(d) From the main floor and each balcony of the auditorium there shall 
be at least two paths of exit independent of one another. Stairways or ramps 
serving balconies above the first or lowest balcony shall be enclosed and shall 
discharge directly into a street or open court independently of the other 
required exit serving the same balcony or balconies and independently of the 
paths of exit from the main floor. Such stairways or ramps may serve also 
as exits from the first or lowest balcony. A stairway or ramp serving as an 
exit only from the first or lowest balcony need not be enclosed and the path 
therefrom may join a path of exit from the main floor. Where a path of exit 
joins another at an angle, the common path of exit shall be at least as wide as 
the sum of the widths of the paths so joined, and the partition or railing which 
bounds a path so joining another shall either be stopped back from the nearer 
side of the common path a distance equal to the width of the joining path or 
shall extend such distance beyond the side of the common path, thus enabling 
persons either to join the common path before turning or to enter and turn 
before joining the common path. 

(e) Exit stairways or ramps from balconies shall not extend below the 
level at which they discharge from the building. 

(f ) Exits and paths of exit, except from boxes seating less than twenty-five 
persons, shall be not less than five feet wide at any point. The aggregate 
width of the paths of exit specified heretofore in this section which serve one or 
more divisions of the auditorium shall be at least twenty inches for every one 
hundred persons for whom seats are provided in the division or divisions so 
served. In calculating the required width of each path of exit, persons seated 
in the auditorium shall be allotted to those exits therefrom which they can 
most quickly reach in an emergency, assuming that the emergency exits 
hereinafter specified are not used, and upon any other reasonable assumption. 

(g) In addition to the exits specified in paragraphs (c), (d), (e) and (f) 
of this section, hereinafter called normal exits, there shall be provided a system 
of emergency exits as specified in this paragraph and in paragraphs (h) and (i). 
Emergency exits from the auditorium shall be at least five feet wide and 
there shall be at least one such exit from each side of the main floor and of 
each balcony as remote as practicable from the normal exits. Emergency 
exits from the main floor shall be exits from the building or shall be con- 
nected by passageways with exits from the building independent of the 
normal exits. The paths of emergency exit from the main floor shall be 
not less than five feet wide, nor shall the aggregate width be less than five 
inches for every one hundred persons served. The paths of exit from the 
emergency exits from balconies shall be either of inside type as specified in 
paragraph (h) or of outside type as specified in paragraph (i) of this section, 
or a combination of the two types; provided, that the aggregate width of 
the paths of emergency exit shall have five inches in width of inside path or 
ten inches in width of outside path for every one hundred seats in the balcony 
or balconies served. 

(h) An inside path of emergency exit, referred to in the preceding para- 
graph, shall consist of a foyer with at least fifty square feet of floor for each 
emergency exit served, and an enclosed stairway or ramp with outside ventila- 

(36) 



Sec. 305 

tion, with a direct exit from the building, or an enclosed passageway leading 
to such an exit, independent of normal exits, or an exit to another building 
or fire division of Type I or Type II construction. An exit to another build- 
ing or fire division shall be through a lobby or vestibule of at least one 
hundred square feet in floor area with outside ventilation and with self- 
closing Class A fire doors at entrance and exit and shall lead, through ade- 
quate corridors, stairways and passageways, to the street. No such exit 
shall be made through a building or fire division of Group E occupancy. 
Inside emergency exits shall be not less than three feet wide. 

(i) An outside path of emergency exit, referred to in paragraph (g) of 
this section, shall consist of an exterior fire escape balcony not less than 
four feet wide at each emergency exit from a balcony and not more than 
six inches below the sill thereof. Such balconies at the highest level shall 
be at least eight feet long and at lower levels at least twelve feet long. Fire 
escape stairs of rise not exceeding eight and one half inches and tread not 
less than nine and one half inches and not less than thirty inches wide shall 
lead from all such balconies to the ground. The lowest runs may be hinged 
and counterweighted. Exterior fire escapes shall be located either in a 
street or in an open court. Such courts shall be at least six feet wide and 
open to the sky for the full depth of the auditorium and shall be connected 
with a street by an open court or an enclosed passageway ten feet high, 
either of which shall be at least six feet wide. Every such court or passage- 
way shall have such additional width as may be necessary, if any, to pro- 
vide, when the fire escape stairs are in position for use, the clear width 
required for it as a path of emergency exit and as a path of normal exit if so 
used. 

(j) At least one exit, three feet wide, shall be provided on each side of 
the stage. These exits shall open directly upon a street, or on a passageway 
or court not less than three feet wide, leading to a street. Ladders may 
be provided as exits from fly gallery and gridiron. Each tier of dressing 
rooms shall be provided with at least two remote exits not less than thirty 
inches wide. 

(k) All exit and entrance doors or gates in any path of exit shall swing 
in the direction of egress and if provided with latches, such latches shall be 
of self-releasing type such as panic bolts or similar devices, of non-corrodible 
metal, which will permit the door to open when pressed against. All doors 
shall be so installed as not in any position to decrease the width of any door- 
way (except that in which it is installed), stairs, landing, passageway or 
corridor below the width required. 

(1) No mirrors, false doors or windows shall be so placed as to give the 
appearance of a doorway or exit, hallway or corridor. 

(m) In buildings of Group A the rise of stairs shall not exceed seven 
and one half inches nor shall the tread be less than ten and one half inches. 
There shall be no flights of stairs of more than fifteen or less than three risers 
between landings. 

(n) A landing between two flights of stairs in the same direction shall 
be at least as wide as the stairway and at least four feet long in the direction 
of travel. Stairs turning at a right angle shall have a square or rectangular 

(37) 



Sees. 305=306 

landing the full width of the respective stairwaj's, except that the outer line 
of the landing shall be curved to a radius not less than two feet, or bevelled 
two feet, to avoid a deep corner. Where stairs return directly on them- 
selves, a landing without steps shall be provided at least as wide as the stairs, 
and the outer corners shall be curved or bevelled. Winders may be provided 
only in stairs from boxes seating less than twenty-five persons. Where 
two side nights of stairs join and continue in a common flight, a landing 
without winders shall be provided and the width of the common flight shall 
be equal to the sum of the widths of the side flights. A door opening into a 
stairway shall not open immediately upon a flight of stairs, but a landing 
at least three feet long in the direction of travel shall intervene. 

(o) All stairways shall have, on both sides, strong hand rails firmly 
secured about three feet high above the upper tread at each riser, except 
that stairs less than three feet wide need have a rail only on one side. 

(p) Stairways over eight feet wide shall be provided with a central rail, 
not less than two inches in diameter, placed at a height of about three feet 
above the upper tread at each riser, firmly supported on metal standards. 
Stairways over twelve feet wide shall have such intermediate rails dividing 
the stairs into equal runs not over six feet wide. Where hand rails are 
fastened to walls, there shall be a minimum clearance of two inches between 
the rail and the wall, and the upper ends of wall hand rails shall be returned 
to wall or posts. At the head of each flight of stairs there shall be a post or 
standard at least six feet high, to which the intermediate rail or rails shall 
be fastened. 

(q) Except as otherwise specified in this section, the provisions of Part 
18 shall apply to exits from Group A buildings. 

[ ]As amended by Ord. 1943, ch. 2 ] 

*Sect. 306. Aisles and Seating. — fa) In auditoriums, aisles having 
seats on both sides shall be not less than thirty inches in width at the end 
remote from an exit and- shall be widened by two inches for each ten feet in 
length measured toward the exit. Aisles having seats on one side only shall 
be not less than twenty-four inches wide at the end remote from an exit, and 
shall be widened toward the exit by two inches for each ten feet in length. 
Side aisles serving more than one exit shall be of uniform width between exits 
and such width shall be not less than that required by this paragraph at a 
point midway between the extreme exits. 

(b) Aisles shall be so arranged that not more than six seats shall intervene 
between any seat and the nearest aisle. 

(c) There shall be no obstructions of any kind in an aisle. Aisles on the 
main floor and in balconies may be sloped or stepped. When sloped, the 
slope shall not exceed two inches vertical in ten inches horizontal. Where 
stepped the rise shall not exceed twenty-one inches in a horizontal distance of 
thirty-two inches. Stepped aisles shall not be construed to be stairways. 

(d) The main floor of auditoriums shall have a cross-over aisle, either 
open or enclosed, at the rear extending from side to side of auditorium. Fur- 
thermore, if there are more than thirty-five rows of seats, there shall be in 
addition at least one cross-over aisle extending from side to side of the audi- 

(38) 



Sees. 306=308 

torium, and in no case shall there be more than thirty-five rows of seats 
between cross-over aisles. Balconies with more than five rows of seats shall 
have at least one cross-over aisle extending from side to side of balcony, 
and in no case shall there be more than twenty rows of seats between cross- 
over aisles. Cross aisles shall be not less than three feet wide in the clear 
and shall lead to exits that are easily accessible. Vomitories shall be considered 
entrances and exits. 

(e) Seats shall be spaced not less than thirty-two inches except that 
seats with backs less than one inch thick may be spaced not less than thirty 
inches back to back. Seats in stepped balconies shall be spaced not less than 
thirty-two inches back to back. No seats shall be less than eighteen inches 
in width center to center. All seats shall be securely fastened to the floor, 
except as otherwise provided in this section. 

(f) Seats in boxes accommodating less than twenty-five persons need 
not be fastened to the floor. Boxes accommodating twenty-five persons or 
more shall be considered balconies. 

[ *As amended by Ord. 1943, ch. 2 ] 

fSect. 307. Exit Lights. — Over every exit doorway in any path of exit, 
on the inside, and over every opening to a fire escape, on the inside, there 
shall be an illuminated sign bearing the word "EXIT" or "FIRE ESCAPE", 
respectively, in letters not less than four inches high. Each sign shall be 
provided with two electric lamps. 

[ fAs amended by Ord. 1943, ch. 2 ] 

{Sect. 308. Light and Ventilation. — (a) Dressing rooms, work 
shops, toilet rooms, auditoriums, foyers, and other public rooms shall be 
provided with light and ventilation by means of windows and skylights with 
an area not less than one eighth the floor area in each room, or they shall be 
provided with artificial light and a mechanically operated ventilating system. 
The mechanically operated ventilating system shall provide for four complete 
air changes per hour in rooms where required and in the auditorium shalj 
supply at least fifteen cubic feet of fresh air per minute for each occupant 
thereof. If the velocity of the air entering the room exceeds five feet per 
second, the opening must be placed more than eight feet above the floor 
directly beneath. Adequate means shall be provided for the removal of 
foul air. 

(b) Light shall be electric. Auditorium lights shall be on circuits separate 
from those of the stage and the remainder of the building, and shall be so 
arranged that they can be turned on from the stage and from at least one other 
approved point in the front of the house, with approved indicators to show 
when the lights are on. 

(c) Lights in foyers, stairways, corridors and other paths of exit shall be 
on circuits separate from those of the stage, auditorium and the remainder 
of the building and shall be so arranged that they can be turned on from the 
stage and from at least one other approved point in the front of the house, 
with approved indicators to show when the lights are on. 

(d) Exit sign lights and selected lights in foyers, auditoriums, stairways, 
corridors and other paths of exit sufficient to provide illumination for egress 

(39) 



Sees. 308=310 

of the audience in case of emergency shall be wired on separate circuits, and 
these lights, hereinafter referred to as emergency lights, shall be kept lighted 
when the building is occupied, except that outside balconies and fire escapes 
need not be lighted before sunset nor auditorium lights during a performance. 
The emergency lights may also include lights on switchboards, in projection 
rooms, in boiler rooms and at other critical points. Emergency lights shall 
be protected from possible physical damage. 

(e) The emergency lights shall be provided with a second or emergency 
source of current and a transfer switch which will automatically disconnect 
the normal service and instantly connect the emergency service when the 
voltage of the normal service falls below fifty per cent of the nominal lamp 
voltage and which will also automatically disconnect the emergency service 
and instantly connect the normal service when the voltage of the latter is 
restored to eighty per cent of the nominal lamp voltage. The emergency 
source of current shall be either : — 

(1) A separate feeder of the service company other than that from 
which the normal service is taken, or 

(2) A separate feeder from a reliable generating plant independent of 
that from which the normal service is taken, or 

(3) An approved storage battery, or 

(4) Illuminating gas. 

(f) Glass in lighting fixtures hung in auditoriums, lobbies or other public 
places shall be secured from falling by an approved method. 

[ |As amended by Ord. 1943, ch. 2 and 9 ] 

Sect. 309. Stage Ventilators, Group A Occupancy. — (a) There 
shall be one or more ventilators, constructed of metal or other non-combustible 
material, near the center and above the highest part of the stage. Such 
ventilator or ventilators shall be raised above the stage roof and shall have a 
total ventilating area at least equal to ten per cent of the floor space behind 
the proscenium wall, at the stage floor level, not separated from the stage by 
a two-hour separation. 

(b) Doors or covers for ventilators shall open by gravity. Doors or 
covers shall be held closed and manually operated by means of cords extending 
to each side of the stage. These cords shall each be equipped with three 
fusible links one of which shall be placed in the ventilator above the main 
roof level and the other two at approved points not affected by sprinkler 
heads. Fusible links shall be of an approved type which will release at a 
temperature of one hundred and sixty degrees Fahrenheit. Each ventilator 
shall be opened and closed at least once before each performance. 

(c) Glass, if used in ventilators, may be either plain or wired. If plain 
glass is used, a suitable wire netting shall be placed both above and below 
the glass. 

Sect. 310. Proscenium. — (a) The stage portion shall be separated 
from the auditorium by not less than four-hour fire-resistive construction, as 
specified in Part 22. Such separation shall be known as the proscenium wall. 
This wall may be offset as desired, but such offset shall also be of not less 

(40) 



Sees. 310=311 

than four-hour fire-resistive construction. The proscenium wall shall not be 
finished or covered with combustible materials. 

(b) The proscenium opening, the main opening for the viewing of per- 
formances, shall be provided with a proscenium curtain as follows : — 

(1) The proscenium curtain shall be of incombustible and fire-resistive 
material. If of fabric, it shall be of asbestos cloth containing not over ten 
per cent by weight of cotton or other combustible fibre, shall be reinforced 
by wire and shall weigh not less than three pounds per square yard. 

(2) Proscenium curtains of other materials than fabric, which are able 
to withstand a standard fire test, as specified in Part 22, for thirty minutes, 
may be used with the approval of the commissioner. 

(3) If the proscenium opening is not more than thirty-five feet wide 
the curtain shall have a rigid metal member at the top and at the bottom 
edge protected by the fabric on both stage and auditorium sides. If the 
proscenium opening is more than thirty-five feet wide the curtain shall 
have a rigid steel frame on all sides braced and constructed to the satis- 
faction of the commissioner and protected from fire on both stage and audi- 
torium sides. 

(4) The proscenium curtain shall extend into non-combustible grooves 
at the side a distance of at least twelve inches and the edges of the curtain 
shall be retained in the groove by means of a taut steel cable or by other 
approved means. The curtain shall overlap the top of the proscenium 
opening not less than eighteen inches. At the bottom edge the curtain 
shall be padded for a depth of at least four inches with flexible incombustible 
material. 

(5) The proscenium curtain shall be so rigged, counter balanced, and 
operated that it can be quickly released to descend by gravity, and com- 
pletely close the opening in case of fire. The releasing device and its 
location shall be approved by the commissioner. 

(6) The proscenium curtain shall be raised and lowered at least once 
before every performance and shall be lowered at the close of every per- 
formance. The operation of the curtain by means of the releasing device 
shall be tested at intervals as required by the commissioner. 

(c) The proscenium wall may have, in addition to the proscenium opening 
not more than two openings at the orchestra^ pit level and two openings at 
about the auditorium floor or stage level, none of which shall be more than 
twenty-five square feet in area. Each such opening shall be protected on 
each side of the wall by a Class A fire door as specified in Part 22. Ventilating 
ducts may pass through the proscenium wall, provided they are equipped 
with automatic-closing shutters of approved fire-resistive construction with 
fusible links. 

Sect. 311. Stage Construction. — (a) The portion of the stage 
floor used in the working of scenery, traps or other mechanical apparatus, 
may be of Type III floor construction, and steel beams need not be protected 
against fire. This construction shall not extend beyond the proscenium 
wall or the proscenium curtain, and shall not exceed the width of the pro- 
scenium opening by more than three feet on each side. All other portions 
of the stage shall be of Type I construction as specified in Part 16. The room 

(41) 



Sees. 311=314 

or rooms under a stage of other than Type I construction shall not be used 
for storage or for any purpose other than the working of traps and mechanical 
apparatus necessary for a performance on the stage. 

(b) Gridirons, fly galleries, and pin rails shall be constructed of incom- 
bustible materials, but fireproofing of metal shall not be required. 

(c) A protecting hood of incombustible material shall be provided over 
and the full length of the stage switchboard. The switchboard shall be 
protected on the sides and back by a grille of three-sixteenths inch wire with 
not more than two-inch mesh, or by partitions of incombustible materials 
having a one-hour fire-resistive rating, and on the front by a railing not 
less than three feet high. 

Sect. 312. Dressing Rooms and Workshops. — The dressing rooms, 
workshops and storerooms shall be separated from the stage by a two-hour 
separation as specified in Part 13. 

Sect. 313. Fire=Extinguishing Apparatus. — (a) Automatic sprinklers 
shall be provided throughout, except in auditoriums, foyers, lounges, entrances, 
exits and projection rooms. 

(b) The proscenium opening shall be equipped with an effective water 
curtain by means either of automatic sprinkler heads of suitable design, or 
open heads controlled by either of two valves on the stage, one on each side 
of the proscenium opening. 

(c) A portable fire extinguisher or extinguishers of approved type shall 
be provided on the outside of each projection room near the door or doors. 

(d) Portable extinguishers, not less than one for every two thousand square- 
feet of floor area, shall be provided throughout except in entrances and exits. 

(e) First aid hose stations shall be provided throughout, except in pro- 
jection rooms, auditoriums, foyers, lounges, entrances, exits and other rooms 
used by the public. There shall be one station each side of the stage. 

(f) Fire department standpipes shall be provided in buildings more than 
seventy feet high. 

Sect. 314. Projection Room. — The size, construction, arrangement 
and equipment of a projection room shall conform to the requirements of 
sections seventy-two to eighty-eight, inclusive, of chapter one hundred and 
forty-three of the General Laws, and to the regulations established thereunder 
by the commissioner of public safety of the commonwealth of Massachusetts. 



(42) 






Sec. 401 



PART 4. 



SPECIAL REQUIREMENTS FOR GROUP B OCCUPANCY: 

HALLS. 

Section 

401 — Group B Occupancies: Type, Height, Area, 

402 — Separation of Occupancies. 

403 — Exterior Walls. 

404 — Enclosure of Vertical Openings. 

405 — Exits and Entrances. 

406 — Aisles and Seating. 

407 — Exit Lights. 

408 — Light and Ventilation. 

409 — Stage and Proscenium. 

410 — Dressing Rooms, Workshops and Boiler Rooms. 

411 — Fire=Extinguishing Apparatus. 

412 — Projection Room. 

*Section 401. Group B Occupancies: Type, Height, Area, — 

(a) Group B shall include places where persons may assemble for such 
and similar purposes as are indicated in the following list of categories, where 
the main floor exceeds nine hundred square feet in area or where the total 
floor area, including a balcony, exceeds one thousand square feet. 

(1) Churches in the commonly accepted sense of religious societies. 

(2) Rooms and halls where people may engage in any form of dancing. 

(3) Auditoriums, Entertainment and Exhibition Halls without gridiron 
equipped stages as defined in Group A. 

(4) MoviDg picture theatres without gridiron equipped stages as 
defined in Group A. 

(5) Gymnasiums and sports events halls. 

(6) Meeting and gathering places of fraternal, social, civic, and philan- 
thropic organizations. 

(b) Buildings or parts of buildings classified for occupancy in Group B, 
and of the several types of construction, shall not exceed in height and area of 
units of occupancy the following limits: — 



Type of 
Construction. 


Stories. 


Maximum Area of Unit (Square Feet). 


I 


Not hereby limited. 
4 
1 

4 

1 

3 
1 

Not allowed. 
1 


Not hereby limited. 


II 

Ill 


18,000 

Not hereby limited. Maximum distance in path 

of exit, 175 feet. 
17,000 


IV 


Not hereby limited. Maximum distance in path 

of exit, 150 feet. 
12,000 


V. 


Not hereby limited. No structure of combustible 
material to support seats or aisles to be super- 
imposed on the floor construction. Maximum 
distance in path of exit, 100 feet. 


VI 


5,000 







(43) 



Sees. 401=405 

The maximum area may be increased proportionately within the limits 
given as the number of stories is decreased from the maximum. 

(c) The first floor of all buildings more than two stories in height shall be 
of Type I construction. No assembly hall of floor area exceeding thirty-six 
hundred square feet and no group of assembly halls of aggregate floor area 
exceeding forty-eight hundred square feet shall be above the first story unless 
the building is of Type I or Type II construction. 

(d) The maximum area provided in this section may be increased fifty 
per cent if the entire floor area is protected by automatic sprinklers. 

[ *As amended by Ord. 1943, ch. 2 ] 

Sect. 402. Separation of Occupancies. — Group B occupancies shall be 
separated from other occupancies, and fire divisions of Group B occupancy 
shall be separated from adjoining fire divisions as specified in Part 13. 

fSect. 403. Exterior Walls. — (a) Exterior walls or parts of walls, 
except where fronting on a street, which are less than five feet from a property 
line, shall be of four-hour fire-resistive construction without openings, except 
that openings in such walls at the ends of courts shall be allowed when pro- 
tected by fire windows or Class B fire doors. Such walls or parts of walls 
which are five feet or more, but less than ten feet from a property line shall 
be of at least two-hour fire-resistive construction and all openings therein shall 
be protected by fire windows or Class B fire doors. 

(b) Every portion of an exterior wall which faces, at a distance of less than 
twenty feet, the further side of a street, or a combustible wall or roof or an 
unprotected opening in a wall or roof of another building on the same lot, 
shall be of at least two-hour fire-resistive construction, and all openings in 
such portions shall be protected by fire windows or Class B fire doors. 

(c) The commissioner may waive the requirements of this section, for the 
protection or prohibition of openings in walls, temporarily pending construc- 
tion on an adjoining lot or across a street, provided the owner agrees in a writing 
recorded in the registry of deeds to comply with the said requirements on 
demand of the commissioner. 

[ fAs amended by Ord. 1943, ch. 2 ] 

Sect. 404. Enclosure of Vertical Openings. — (a) Main stair or ramp 
exits from only the second story need not be enclosed. Stairways or ramps 
which extend only from a balcony in a hall to the main floor level need not be 
enclosed. Other stairways and ramps which pierce only one floor shall be 
enclosed in the story above or below but such stairways which serve as re- 
quired exits from one story shall be enclosed in the other. Other stairways 
and ramps shall be enclosed in all stories in which they occur. 

(b) Elevator shafts, ventilation shafts and other vertical openings except 
stairways and ramps, shall be enclosed. 

JSect. 405. Exits and Entrances. — (a) Group B buildings shall front 
upon a public street not less than twenty feet wide or upon an open area not 
less than twenty feet wide leading to a public street. In this front shall be 
located the main entrance of the building. The main entrance or entrances, 
which may also serve as exits, shall have in the aggregate twenty inches of 
clear width for each one hundred persons to and including one thousand per- 

(44) 



Sec. 405 

sons, with an additional ten inches for each additional one hundred persons 
to and including one thousand additional persons, and an additional five 
inches for each additional one hundred persons over two thousand persons. 
In a one story or two story building the width of entrance shall be based upon 
the total seating capacity of the halls served by it. In a building of three or 
more stories the width of entrance shall be based upon the maximum total 
seating capacity of the halls served by it which are contained in any two 
stories. (See definition of "seating capacity.") 

(b) Adjacent to the main floor and to each balcony, if any, of an assembly 
hall and between the hall and its main entrance in the path of normal entrance 
and egress, except in the first story, there shall be a foyer, consisting of a lobby, 
corridor or passageway, one or more, the aggregate floor area of which shall 
be at least equal to one square foot for each seat in the seating capacity of the 
hall or balcony so served; provided, that one such area may serve two or more 
halls or balconies on the same floor level if large enough for the largest two halls 
so served. A hall, with a balcony seating not more than one hundred and 
fifty persons, may have a common foyer. A foyer shall have a width of at 
least ten inches for each one hundred seats in the seating capacity of the 
largest two halls served by it. 

(c) Assembly halls having a seating capacity of fifteen hundred or less 
shall have exits with an aggregate width of at least twenty-four inches for 
each one hundred seats thereof and no exit shall be less than three feet wide. 
Halls having a seating capacity of five hundred or less shall have at least two 
remote exits. Halls having a seating capacity of more than five hundred, but 
not more than eight hundred, shall have at least three remote exits. Halls 
having a seating capacity of more than eight hundred, but not more than one 
thousand, shall have at least four remote exits of which two shall be at least 
five feet wide. Halls having a seating capacity exceeding one thousand shall 
have at least four remote exits five feet wide. Every assembly hall shall have 
at least two remote and independent paths of exit. Halls having a seating 
capacity of more than fifteen hundred shall have exits meeting the require- 
ments for normal and emergency exits from the auditoriums of Group A 
buildings. Every balcony seating more than twenty-five persons shall have 
two remote exits. 

(d) At least one exit from every hall or balcony shall lead into the foyer 
thereof and all such exits may lead into the foyer if it has two remote exits. 
Exterior stairways and ramps shall not serve as required exits of Group B 
buildings except the emergency exits required for halls seating more than 
fifteen hundred. Exits from foyers and all paths of exit from doorways 
from assembly halls shall be at least forty-four inches wide and shall have 
an aggregate width at least equal to twenty inches for each one hundred 
seats in the seating capacity of the halls of any one story served by them. 
No point on the main or balcony floor of an assembly hall shall be further 
from the nearest exit from the story than one hundred and fifty feet along a 
path of exit. 

(e) Enclosed stairways or ramp exits shall discharge directly through an 
exit from the building or through an enclosed corridor leading to an exit from 
the building. 

(45) 



Sees. 405-406 

(f) Doorways from a room leading into a stair enclosure shall have single 
acting, self-closing doors opening in the direction of any path of exit. 

If doors in exit doorways in any path of exit have latches, such latches shall 
be panic bolts or similar approved devices, of non-corrodible metal. 

(g) Stairs shall have a handrail on each side. The upper ends of handrails 
shall return to the wall or to a post. 

(h) Except as otherwise specified in this section the provisions of Part 18 
shall apply to exits from Group B buildings. 

[J As amended by Ord. 1943, ch. 2 ] 

*Sect. 406. Aisles and Seating. — (a) Aisles having seats on both 
sides shall be not less than thirty inches in width at the end remote from an 
exit and shall be widened by two inches for each ten feet in length measured 
toward the exit. Aisles having seats on one side only shall be not less than 
twenty-four inches wide at the end remote from an exit, and shall be widened 
toward the exit by two inches for each ten feet in length. Side aisles serving 
more than one exit shall be of uniform width between exits and such width 
shall be not less than that required by this paragraph at a point midway 
between the extreme exits. 

(b) Aisles shall be so arranged that not more than six seats shall intervene 
between any seat and the nearest aisle. 

(c) There shall be no obstructions of any kind in an aisle. Aisles on the 
main floor and in balconies may be sloped or stepped. When sloped, the slope 
shall not exceed two inches vertical in ten inches horizontal. When stepped, 
the rise shall not exceed twenty-one inches in a horizontal distance of thirty- 
two inches. Stepped aisles shall not be construed to be stairways. 

(d) The main floor of auditoriums shall have a cross-over aisle, either 
open or enclosed, at the rear extending from side to side of auditorium. Fur- 
thermore, if there are more than thirty-five rows of seats there shall be in 
addition at least one cross-over aisle extending from side to side of the audi- 
torium, and in no case shall there be more than thirty-five rows of seats 
between cross-over aisles. Balconies with more than five rows of seats shall 
have at least one cross-over aisle extending from side to side of balcony, and 
in no case shall there be more than twenty rows of seats between cross-over 
aisles. Cross aisles shall be not less than three feet wide in the clear and 
shall lead to exits that are easily accessible. Vomitories shall be considered 
extrances and exits. 

(e) Seats shall be spaced not less than thirty-two inches except that 
fixed seats with backs less than one inch thick may be spaced not less than 
thirty inches back to back. Seats in stepped balconies shall be spaced not 
less than thirty-two inches back to back. No seats shall be less than eighteen 
inches in width center to center. 

(f) In a hall or balcony seating more than one hundred and fifty persons, 
seats shall either be fastened to the floor or approved means shall be provided 
so that the relative position of seats shall be maintained. In smaller halls 
or balconies, unless the seats are so secured, the aisles shall be four inches wider 
than as provided in paragraph (a) of this section. 

[ *As amended by Ord. 1943, ch. 2 ] 

(46) 



Sees. 407=408 

*Sect. 407. Exit Lights. — Over every exit doorway in any path of exit 
on the inside, there shall be an illuminated sign bearing the word "EXIT" 
in letters not less than four inches high. Each sign shall be provided with 
two electric lamps. 

[ *As amended by Ord. 1943, ch. 2 ] 

fSect. 408. Light and Ventilation. — (a) Assembly halls, foyers, 
toilet rooms and other public rooms shall be provided with light and ventilation 
by means of windows or skylights with an aggregate area not less than one 
eighth the floor area in each room, or they shall be provided with artificial 
light and a mechanically operated ventilating system. The mechanically 
operated ventilating system shall provide for four complete changes of air 
per hour, and in assembly halls shall supply at least fifteen cubic feet of fresh 
air per minute for each occupant thereof. If the velocity of the air entering 
the rooms exceeds five feet per second, the opening must be placed more than 
eight feet above the floor directly beneath. Adequate means shall be provided 
for the removal of foul air. 

(b) Registers or ventilating ducts for supplying air to or exhausting air 
from stages shall be equipped with automatic-closing shutters with fusible 
links. 

(c) Lights for stages shall be on circuits separate from the lights of 
the remainder of the building. Lights in corridors, stairways, and other 
parts of exits shall be suitably protected. 

(d) In an assembly hall having a seating capacity in excess of eight 
hundred the exit sign lights and selected lamps in foyers, auditoriums, stair- 
ways, corridors and other paths of exit therefrom sufficient to provide illu- 
mination for egress in case of emergency shall be wired on a separate 
emergency circuit with a second source of current as provided for in Group A 
occupancy. Exit sign lights shall be kept lighted when the hall is occupied, 
and other emergency lights, except auditorium lights, when the hall is 
occupied except before sunset in rooms, corridors and stairways sufficiently 
lighted by windows. 

(e) The emergency lights shall be provided with a second or emergency 
source of current and a transfer switch which will automatically disconnect 
the normal service and instantly connect the emergency service when the 
voltage of the normal service falls below fifty per cent of the nominal lamp 
voltage and which will also automatically disconnect the emergency service 
and instantly connect the normal service when the voltage of the latter is 
restored to eighty per cent of the nominal lamp voltage. The emergency 
source of current shall be either: — 

(1) A separate feeder of the service company other than that from which 
the normal service is taken, or 

(2) A separate feeder from a reliable generating plant independent 
of that from which the normal service is taken, or 

(3) An approved storage battery, or 

(4) Illuminating gas. 

[ ]As amended by Ord. 1943, ch. 2 and 9 \ 

(47) 



Sees. 409=412 

Sect. 409. Stage and Proscenium. — (a) Where a stage or platform 
is without provisions for scenery, no separation from the auditorium shall 
be required, and such stage or platform may be of the same type of con- 
struction as the auditorium floor; or it may be constructed of wood, if the 
auditorium floor extends under the full area of such stage or platform. 

(b) Where a stage has provisions for standing scenery only, such stage 
shall be separated from the auditorium by a proscenium wall of not less 
than two-hour fire-resistive construction. Each opening through this wall, 
other than the proscenium opening, shall not exceed twenty-five square 
feet in area, and shall be protected by a Class A fire door. Where such 
stage exceeds fifteen feet in depth, or where the proscenium opening exceeds 
twenty-five feet in width or twelve feet in height, the proscenium opening 
shall be provided with a proscenium curtain as specified for theatres in Part 3. 
Where such stage is less than fifteen feet in depth, and the proscenium open- 
ing is less than twenty-five feet in width and twelve feet in height, the pros- 
cenium curtain shall be either of asbestos fabric or of cotton or other fabric 
flame-proofed by approved chemical process. 

Sect. 410. Dressing Rooms, Workshops and Boiler Rooms. — 

Dressing rooms, workshops and store rooms near the stage shall be separated 
therefrom by a two-hour separation as defined in Part 13. Every boiler 
room or room containing a heating plant shall be separated from the rest of 
the building by a two-hour separation. 

*Sect. 411. Fire Extinguishing Apparatus. — (a) Cellars and base- 
ments, stages with proscenium walls, accessible areas — other than the 
Assembly Hall, entrances and exits, and projection rooms shall be equipped 
with Automatic Sprinklers. Attics, the space under stages and other such 
spaces, if available for storage, shall be equipped with Automatic Sprinklers. 

(b) In buildings where Group B occupancy is located above occupancy 
of other grouping or groupings, the areas of the other grouping or groupings 
shall be equipped with Automatic Sprinklers. 

(c) In every Assembly Hall where stage shall have a proscenium wall as 
required by Section 409 (b), the proscenium opening shall be equipped with a 
water curtain as specified in Part 3. 

(d) A portable fire extinguisher of approved type shall be provided out- 
side of every projection room near each projection room door. 

(e) In buildings more than two stories high, either portable extinguishers, 
not less than one for every two thousand square feet of floor area, or first 
aid standpipes, shall be provided in spaces other than projection rooms, but 
first aid standpipes shall not be provided in assembly halls, corridors, foyers, 
exits and other rooms used by persons assembled in such halls. 

(f) Fire department standpipes and first aid standpipes shall be provided 
in buildings more than seventy feet high. 

[ *As amended by Ord. 1943, ch. 2 ] 

fSect. 412. Projection Room. — A projection room shall have a floor 
of incombustible material supported on a concrete base not less than three 

(48) 



Sec. 412 

inches in total thickness which may be supported by a floor of the same 
type of construction as that of the building, or of other materials having 
equivalent fire-resistance. A projection room shall have walls and ceiling 
of not less than one-hour fire-resistive construction of incombustible materials. 
In other respects a projection room shall conform to the requirements of 
sections seventy-two to eighty-eight, inclusive, of chapter one hundred and 
forty-three of the General Laws, and to the regulations established there- 
under by the commissioner of public safety of the commonwealth of 

Massachusetts. 

[ fits amended by Ord. 1948, ch. 2 ] 



(49) 



Sec. SOI 



PART 5. 

SPECIAL REQUIREMENTS FOR GROUP C OCCUPANCY: 

SCHOOLS. 

Section 

501 — Group C Occupancy: Type, Height, Area. 

502 — Separation of Occupancies. 

503 — Exterior Walls. 

504 — Enclosure of Vertical Openings. 

505 — Exits. 

506 — Aisles and Seating. 

507 — Light. 

508 — Ventilation and Heating. 

509 — Fire=Extinguishing Apparatus. 

510 — Special Requirements. 

511 — Toilet Accommodations. 

*Section 501. Group C Occupancy: Type, Area. — (a) Group C shall 
include every post-code building used wholly or in part as a school. 

(b) Buildings or parts of buildings classified for occupancy in Group C 
shall be limited as to type of construction, height and area of units, as follows :— 



Type of Construction. 


Stories. 


Maximum Area of Unit (Square Feet). 


I 


Not hereby limited. 
4 
1 
2 
1 
2 
1 
Not allowed. 
1 


Not hereby limited. 


II 


18,000 


Ill 


24,000 
17,000 


IV 


20,000 
12,000 


V 


18,000 

Not allowed. 


VI 


5,000 







The maximum area may be increased proportionately within the limits 
given as the number of stories is decreased from the maximum. 

(c) The maximum area provided in this section may be increased fifty 
per cent if the entire floor area is protected by automatic sprinklers. 

(d) Assembly halls with seating capacity of more than one hundred and 
fifty persons shall conform with the requirements of Part 4 and, in addition, 
the width of exits shall be computed in multiples of twenty inches for each 
one hundred seats. 

(e) Every Group C post-code building in the first or second fire zone 
shall be of Type I or Type II construction. 

(50) 



Sees. 501-504 

(f) When school usage involves special conditions such as the use of 
hazardous, highly inflammable or explosive materials or liquids or any other 
special occupancy that is a hazard, they shall also conform to the special 
requirements of that occupancy or hazard. 

(g) Pre-code buildings or parts of buildings involving a change of occu- 
pancy to Group C, whether or not altered or enlarged shall conform to the 
general requirements of this section as they shall be interpreted by the com- 
missioner as delineated in Section 107, paragraph (e), and they shall be limited 
as to type of construction, (number of stories,) and area of units as follows: 



Type of Construction. 


Stories. 


Maximum Area of Unit (sq. ft.) 


I 


Not hereby limited. 
4 
1 
5 
5 
Not allowed. 
2 


Not hereby limited. 


II 


18,000 


Ill 


24,000 

5,000 


IV 


5,000 


V 




VI 


4,000 







[ *As amended by Ord. 1943, ch. 3 ] 

Sect. 502. Separation of Occupancies. — Group C occupancies shall 
be separated from other occupancies, and fire division of Group C occupancy 
shall be separated from adjoining fire divisions as specified in Part 13. 

fSect. 503. Exterior Walls. — (a) Exterior walls or parts of walls, 
except where fronting on a street, which are less than five feet from a property 
line, shall be of four-hour fire-resistive construction without openings. Such 
walls or parts of walls which are five feet or more, but less than ten feet from 
a property line, shall be of at least two-hour fire-resistive construction and 
all openings therein shall be protected by Class B fire doors or fire windows. 

(b) Every portion of an exterior wall which faces, at a distance of less 
than twenty feet, the further side of a street, or a combustible wall or roof, 
or an unprotected opening in a wall or roof of another building on the same 
lot, shall be of at least two-hour fire-resistive construction, and all openings 
in such portions shall be protected by Class B fire doors or fire windows. 

(c) The commissioner may waive the requirements of this section, for 
protection or prohibition of openings in walls, temporarily pending con- 
struction on an adjoining lot or across a street, provided the owner agrees 
in a writing recorded in the registry of deeds for Suffolk county to comply 
with the said requirements on demand of the commissioner. 

[ \As amended by Ord. 1943. ch. 3 ] 

JSect. 504. Enclosure of Vertical Openings. — (a) Elevator shafts, 

ventilating shafts, dust chutes and other vertical openings shall be enclosed. 

(b) Stairways and ramps which pierce only one floor shall be enclosed in 

the story above or below, but such stairways or ramps which serve as required 

(51) 



Sees. 504=505 

exits from one story shall be enclosed in the other story. Other stairways 
and ramps shall be enclosed in all stories in which they occur. 
[ %As amended by Ord. 1943, ch. S ] 

*Sect. 505. Exits. — (a) All rooms used for the instruction of pupils 
shall have at least two means of egress; one of which shall open into a corridor, 
stairway, ramp or other egress enclosure; the other shall lead to another 
separate corridor, stairway, ramp or other egress enclosure through intervening 
rooms and intercommunicating doors. The width of exit doors shall be not 
less than thirty-six inches nor less than twenty inches for each one hundred 
occupants thereof. 

(b) Corridors shall have uniform width between exits and shall have a 
clear exit-width not less than six feet, nor less than twenty inches for each one 
hundred persons or fraction thereof allotted to it as a path of exit; provided, 
that the exit-width of a corridor shall not be required to exceed ten feet. 
If classroom doors on one or both sides of a corridor project into it when 
in open position, the width of the corridor shall be increased over its required 
exit-width by one half the sum of such projections. If lockers are installed 
in the walls of corridors on one or both sides, the width of the corridor shall be 
increased over its required exit-width by eighteen inches for each side on 
which lockers are installed. No obstruction shall be placed in corridors 
except that the drip of a recessed drinking fountain or a radiator may project 
into a corridor. If a radiator less than six feet six inches above the floor is 
placed in a path of exit and is not fully recessed, the width of the corridor 
shall be measured from the face of the radiator. 

(c) Each corridor shall have at least two remote exits which shall be 
exits from the story as specified in Part 18. Such exits shall be so located 
that every doorway from a room for pupils to a corridor shall be not more 
than seventy feet from an exit from the corridor. The persons in each room 
having an exit to a corridor shall be allotted to a path of exit through the 
corridor to the nearest exit therefrom for the purpose of computing the 
width of corridors and their exits; provided, that if the mid-length point of 
a corridor between its exits lies in an exit from a room or between two exits 
from a room, the persons in such room may be allotted to either exit from the 
corridor. The width of every exit from a corridor shall be not less than 
forty inches, nor less than twenty inches for each one hundred persons or 
fraction thereof allotted to it. 

(d) Each story of a Group C building shall have at least two remote 
exits. The width of stairs and ramps and of exits from them shall be not less 
than forty inches nor less than twenty inches for each one hundred persons 
or fraction thereof allotted to them and shall be based upon the largest 
number of persons from any one story whom they serve as exits. If doors 
in exit doorways more than four feet wide have latches, such latches shall be 
panic bolts or similar devices of non-corrodible material. 

(e) No intake for a dust or waste paper chute shall open directly upon a 
corridor or enclosed exit, but may open in a closet off a corridor. 

(f) All stairs shall have a handrail on each side. Stairs eighty inches 
or more in width shall have one or more intermediate rails dividing the stairs 

(52) 



Sees. 505=508 

jnto widths less than eighty inches but not less than forty inches; provided, 
that in calculating the capacity as an exit of a stair so divided, each division 
shall be considered an exit. The upper ends of handrails shall be returned 
to the wall or shall so terminate at a post as not to leave a free or projecting 
end. 

(g) Stair landings shall have a width at least equal to that of the stairs. 
No run of stairs shall have more than fifteen nor less than three risers. The 
rise shall not exceed seven and one half inches nor shall the tread be less 
than ten inches. Winders shall not be permitted. 

[ *As amended by Ord. 1943, ch. 3 ] 

Sect. 506. Aisles and Seating. — (a) Classrooms with fixed seats 
shall have aisles at least thirty inches wide next to the windows and at least 
thirty-six inches wide on other sides, and intermediate aisles at least sixteen 
inches wide. 

(b) Unless definitely fixed on the plans the normal seating capacity of 
classrooms shall be determined by dividing the floor area of each room as 
follows: — 

Elementary Schools by 15 square feet 

Intermediate Schools by 17 square feet 

High Schools and Colleges by 19 square feet 

fSect. 507. Light. — (a) Rooms used by pupils for study and class 
work shall have outside windows with a total sash area not less than one 
fifth the floor area of each such room. The windows shall preferably be 
on the long side of a room. The clear height of a room shall be not less 
than ten feet. No room shall be used for class work where an exterior wall 
outside and opposite the required windows shall extend above a line from 
the window sills at thirty degrees above the horizontal unless such wall is 
at least sixty feet from the windows. The possibility of a building on an 
adjoining lot shall be provided for. 

(b) Corridors, stairways and other exits shall have artificial illumination 
which, if electric, shall be on circuits and control separate from other lighting 
in the building. 

\-\As amended by Ord. 1943, ch. 3 and Ord. 1955, ch. 1] 

Sect. 508. Ventilation and Heating. — (a) In all rooms used by 
pupils for school purposes shall be installed a positive system of ventilation 
that will supply fresh air, heated when necessary, and adequately remove 
the foul air. In class, recitation and study rooms there shall be provided 
at least six complete air changes per hour but not less than twenty cubic 
feet of fresh air per minute per pupil normally seated, and in assembly rooms, 
gymnasiums, lunch rooms and vocational rooms at least four complete 
changes of air per hour but not less than fifteen cubic feet per minute per pupil 
for whom seating or work space is provided. In toilets, shower and locker 
rooms at least eight complete air changes per hour shall be provided and 
these rooms shall be ventilated by an exhaust system. 

(b) The heating and ventilating system shall be capable of maintaining, 
when the outside temperature is zero, in gymnasiums and toilets a temperature 

(53) 



Sees. 508-511 

of sixty degrees, in shower and locker rooms appurtenant to gymnasiums 
seventy-five degrees, and in other rooms used by pupils or teachers seventy 
degrees, all by Fahrenheit scale. 

Sect. 509. Fire=Extinguishing Apparatus. — (a) Cellars and base- 
ments, except those portions used for classes, shall be equipped with auto- 
matic sprinklers. Mechanical trade shops, storage rooms and attics available 
for storage shall have automatic sprinklers where required by the commissioner. 

(b) A portable fire-extinguisher of approved type shall be provided out- 
side every projection room near the door. 

(c) In buildings more than two stories high, either portable fire-extin- 
guishers, not less than one for every thirty-five hundred square feet of floor 
area and not less than one in each story, or first aid standpipes shall be pro- 
vided, but first aid standpipes shall not be provided in assembly halls or in 
exits therefrom. 

(d) Fire department standpipes and first aid standpipes shall be provided 
in buildings more than seventy feet high. 

Sect. 510. Special Requirements. — Every boiler room shall be sepa- 
rated from the remainder of the building by a two-hour separation as speci- 
fied in Part 13. 

Sect. 511. Toilet Accommodations. — (a) Adequate toilets shall be 
provided for pupils, with fixtures in accordance with the following table: — 



Number of Pupils of Either Sex. 


Girls. 


Boys. 


Water Closets. 


Water Closets. 


Urinals. 


50 


4 
6 
9 
12 
14 
16 
18 
20 
22 
24 
43 
61 


3 

4 

6 

8 

9 

10 

11 

12 

13 

14 

25 

36 


4 


100 


6 


- 150 


8 


200 


10 


250 


12 


300 


14 


350 


16 


400 


18 


450 


20 


500 


22 


i,000 


40 


1,500 


56 







(b) For intermediate numbers of pupils, fixtures shall be provided by 
interpolation in the table and for numbers in excess of fifteen hundred at the 
rate provided for fifteen hundred. 

(c) Separate toilets shall be provided for the teachers and for the janitors. 



(54) 



Sec. 60! 



PART 6. 

SPECIAL REQUIREMENTS FOR GROUP D OCCUPANCY: 
HOSPITALS AND DETENTION BUILDINGS. 

Section 

601 — Group D Occupancy: Type, Height, Area. 

602 — Separation of Occupancies. 

603 — Exterior Walls. 

604 — Enclosure of Vertical Openings. 

605 — Exits. 

606 — Light and Ventilation. 

607 — Fire=Extinguishing Apparatus. 

608 — Special Requirements. 

609 — Exceptions. 

[610 — Emergency Lights.] 

*Section 601. Group D Occupancy: Type, Height, Area. — (a) 

Group D shall include such occupancies as — 

Division 1. Jails, prisons, reformatories, houses of correction, asylums 
for the insane or feeble minded, the parts of police stations wherein more than 
ten persons may be detained, and similar buildings. 

Division 2. Hospitals, sanitariums, orphanages, nurseries, homes for the 
aged and similar buildings, with sleeping accommodations for ten or more 
persons. 

(b) Buildings or parts of buildings classified for occupancy in Group D 
shall be limited as to type of construction, height and area of units, as follows: — 



Type of Construction. 


Stories. 


Maximum Area of Unit (Square Feet) 


I 


Not hereby limited. 
4 
1 
2 
1 
2 
1 
Not allowed. 
1 


Not hereby limited. 


II 


17,000 


Ill 


20,000 
12,000 


IV 


18,000 
10,000 


V 


15,000 

Not allowed. 


VI 


2,500 







The maximum area may be increased proportionately within the limits 
given as the number of stories is decreased from the maximum. 

(c) Division 1 buildings of Group D shall be of Type I construction 
throughout. The ceilings and partitions of Division 2 buildings of Group D 

(55) 



Sees. 601=605 

more than one story in height shall be of not less than one-hour fire-resistive 
construction and the first floor of such buildings more than two stories in 
height shall be of Type I construction. 

(d) The provisions of this section and of Part 16 shall not be held to pro- 
hibit cell block mezzanine floor construction of unprotected metal without 
limitation as to number and area of such floors provided the entire cell block 
construction is of incombustible materials. 

[ *As amended by Ord. 1943, ch. 3 ] 

Sect. 602. Separation of Occupancies. — Group D occupancies shall 
be separated from other occupancies, and fire divisions of Group D occupancy 
shall be separated from adjoining fire divisions as specified in Part 13. 

Sect. 603. Exterior Walls. — (a) Exterior walls or parts of walls, 
except where fronting on a street, which are less than five feet from a property 
line, shall be of four-hour fire-resistive construction without openings, except 
that openings in such walls at the ends of courts shall be allowed when pro- 
tected by Class B fire doors or fire windows. Such walls or parts of walls 
which. are five feet or more, but less than ten feet from a property line shall be 
of at least two-hour fire-resistive construction and all openings therein shall be 
protected by Class B fire doors or fire windows. 

(b) Every portion of an exterior wall which faces, at a distance of less than 
twenty feet, the further side of a street, or a combustible wall or roof, or an 
unprotected opening in a wall or roof of another building on the same lot, 
shall be of at least two-hour fire-resistive construction, and all openings in such 
portions shall be protected by Class B fire doors or fire windows. 

(c) The commissioner may waive the requirements of this section, for 
protection or prohibition of openings in walls, temporarily pending con- 
struction on an adjoining lot or across a street, provided the owner agrees in 
a writing recorded in the registry of deeds for Suffolk county to comply 
with the said requirements on demand of the commissioner. 

(d) In buildings of Type V construction exterior walls of unprotected 
metal may be considered to meet the requirements of this section for two- 
hour walls. 

Sect. 604. Enclosure of Vertical Openings. — (a) Elevator shafts, 
ventilating shafts and other vertical openings, except stairways and ramps, 
shall be enclosed. 

(b) Stairways and ramps which pierce only one floor shall be enclosed 
in the story above or below but such a stairway or ramp which serves as 
required exit from one story shall be enclosed in the other story. Other 
stairways and ramps shall be enclosed in all stories in which they occur. 

(c) This section and Part 15 shall not be held to require enclosure of 
mezzanine floors in Group D buildings nor of vertical openings in such 
floors, nor of cell block floors if such cell blocks are constructed entirely of 
incombustible materials. 

fSect. 605. Exits. — (a) Every portion of a building shall be provided 
with exits as specified in Part 18. 

(56) 



Sees. 605=609 

(b) In buildings of Division 2 exits from a story, as specified in Part 18, 
shall be so located that no bed shall be more than seventy feet distant from 
at least one such exit measured along the path of exit. 

(c) In buildings of Division 2 exit doorways from patients' rooms shall 
be not less than forty-two inches wide. In such buildings corridors, stair- 
ways, ramps, doorways in stair or ramp enclosures and doorways from the 
building, which serve as required exits, shall be not less than sixty inches 
wide. In such stairways the tread shall not be less than eleven inches nor 
the rise more than six and one half inches; stair landings at turns shall be 
not less than sixty inches wide. 

(d) Except in places of detention, exit doors shall not be fastened against 
egress except by self-releasing latches, panic-bolts or similar devices which 
can readily be opened from the inside at all times without the use of keys 
or any special knowledge or effort. Revolving doors shall not be installed 
in required exit doorways from buildings of Group D occupancy. 

[ fAs amended by Ord. 1948, ch. 8 ] 

{Sect. 606. Light and Ventilation. — Rooms ordinarily occupied by 
human beings shall be provided with light by means of windows in exterior 
walls or skylights in roofs, the area of which shall not be less than one-eighth 
of the floor area, and the same shall be ventilated by windows in exterior 
walls the area of which when open shall not be less than one-sixteenth of the 
floor area of the room, or by mechanically operated ventilating system sup- 
plying at least fifteen cubic feet of fresh air per minute per occupant or 
four complete changes of air each hour, whichever is greater. Rooms accom- 
modating a bed shall be provided with light and ventilation by means of 
windows in exterior walls, the area of which shall not be less than one-eighth 
of the floor area for light and when opened for ventilation not less than 
one-sixteenth of the floor area. 

[ {As amended by Ord. 1948, ch. 8 ] 
Sect. 607. Fire=Extinguishing Apparatus. — (a) All cellars, base- 
ments and shafts shall be protected by automatic sprinklers. Store rooms, 
kitchens and utility rooms in buildings of other than Type I or Type II 
construction shall be protected by automatic sprinklers. 

(b) In all buildings either portable fire extinguishers, not less than one 
for every twenty-five hundred square feet of floor area and at least one in 
each story, or first aid standpipes shall be provided. 

(c) Fire department standpipes and first aid standpipes shall be provided 
in buildings more than seventy feet high. 

Sect. 608. Special Requirements. — (a) Every gas service shall have 
a shut-off easily accessible from the outside and conspicuously marked. 

(b) Every boiler room or room containing heating apparatus shall be 
separated from the rest of the building with a three-hour fire separation, as 
specified in Part 13. 

Sect. 609. Exceptions. — No requirement of this chapter shall be so 
construed as to prohibit the construction of cells in jails or prevent the use 
of locks or safety devices in buildings where it is necessary forcibly to restrain 
the inmates. 

(57) 



Sec. 610 

*Sect. 610. Emergency Lights.— There shall be emergency lights and 
they shall be provided with a second or emergency source of current and a 
transfer switch which will automatically disconnect the normal service and 
instantly connect the emergency service when the voltage of the normal 
service falls below fifty per cent of the nominal lamp voltage and which will 
also automatically disconnect the emergency service and instantly connect 
the normal service when the voltage of the latter is restored to eighty per 
cent of the nominal lamp voltage. The emergency source of current shall be 
either: — 

(1) A separate feeder of the service company other than that from 
which the normal service is taken, or 

(2) A separate feeder from a reliable generating plant independent of 
that from which the normal service is taken, or 

(3) An approved storage battery, or 

(4) Illuminating gas. 

[ *As amended by Ord. 1943, ch. 3 and 9 ] 



(58) 



Sec, 701 



PART 7. 



SPECIAL REQUIREMENTS FOR GROUP E OCCUPANCY: 
COMMERCIAL BUILDINGS OF HAZARDOUS OC= 
CUPANCY. 

Section 

701 — Group E Occupancy: Type, Height, Area, 

702 — Separation of Occupancies. 

703 — Exterior Walls. 

704 — Enclosure of Vertical Openings. 

705 — Exits. 

706 — Light and Ventilation. 

707 — Fire=Extinguishing Apparatus. 

708 — Special Hazards. 

♦Section 701. Group E Occupancy: Type, Height, Area. — (a) Group 
E shall include such occupancies as — 

Division 1. Planing mills, box factories, wood working plants, mattress 
factories, paint shops and dry cleaning plants. 

Division 2. Buildings for the storage of hazardous, highly flammable or 
explosive material. 

(b) Buildings or parts of buildings classified for occupancy in Group 
E shall be limited as to type of construction, height and area of units, as 
follows : — 



Type of 
Construction. 



Height 
Stories. 



Maximum Area of Unit in Square Feet. 



Accessibility from Outside Walls. 



25% 
or less. 



More than 
25% to 50%. 



More than 
50% to 75%. 



More than 

75%. 



I.. 
II. 
Ill 
IV. 

V.. 
VI. 



15 


10,000 


4 


8,000 


4 


8,000 


3 

1 


4,000 
6,000 


1 


6,000 


1 


3,000 



15,000 

10,000 

10,000 

6,000 
8,000 

8,000 

4,000 



20,000 

12,000 

12,000 

8,000 
10,000 

10,000 

5,000 



25,000 

14,000 

14,000 

10,000 
12,000 

12,000 

6,000 



The maximum area of Type IV units may be increased proportionately 
within the limits givenas the number of stories is decreased from the maximum. 

(c) The limitations upon area of the foregoing table shall not apply to 

buildings one story high of Division 1, of Type I construction, the units of 

which may have areas not in excess of fifteen thousand, twenty thousand and 

twenty-five thousand square feet, if accessible from one, two or three sides, 

respectively. 

[ *As amended by Ord. 1943, ch. 3 } 

(59) 



Sees. 702=706 

Sect. 702. Separation of Occupancies. — Group E occupancies shall 
be separated from other occupancies, and fire divisions of Group E occupancy- 
shall be separated from adjoining fire divisions as specified in Part 13. Two 
tenants shall be separated by partitions of at least one-hour and, in a basement, 
at least two-hour fire-resistive rating. 

Sect. 703. Exterior Walls. — (a) Exterior walls or parts of walls, 
except where fronting on a street, which are less than five feet from a property 
line, shall be of four-hour fire-resistive construction without openings, except 
that openings in such walls at the ends of courts shall be allowed when pro- 
tected by Class B fire doors or fire windows. Such walls or parts of walls 
which are five feet or more, but less than ten feet from a property line, shall 
be of at least two-hour fire-resistive construction and all openings therein 
shall be protected by Class B fire doors or fire windows. 

(b) Every portion of an exterior wall which faces, at a distance of less than 
twenty feet, the further side of a street, or a combustible wall or roof, or an 
unprotected opening in a wall or roof of another building on the same lot, 
shall be of at least two-hour fire-resistive construction, and all openings in 
such portions shall be protected by Class B fire doors or fire windows. 

(c) The Commissioner may waive the requirements of this section, for 
protection or prohibition of openings in walls, temporarily pending construc- 
tion on an adjoining lot or across a street, provided the owner agrees in a 
writing recorded in the registry of deeds for Suffolk county to comply with 
the said requirements on demand of the commissioner. 

(d) In buildings of Type V construction exterior walls of unprotected 
metal may be considered to meet the requirements of this section for two-hour 
walls. 

*Sect. 704. Enclosure of Vertical Openings. — (a) Elevator shafts, 
ventilating shafts and other vertical openings except stairways and ramps 
shall be enclosed. 

(b) Mezzanine floors shall be enclosed when otherwise the total floor area 
in one story exposed to a single fire would exceed the maximum area of unit 
specified in section seven hundred and one. Vertical openings in enclosed 
mezzazine floors shall be enclosed as herein provided for other floors. 

(c) Stairways and ramps which pierce only one floor, shall be enclosed in 
the story above or below but such stairways or ramps, which serve as required 
exits from one story, shall be enclosed in the other story. Other stairways 
shall be enclosed in all stories in which they occur. 

[ *As amended by Ord. 1943, ch. 8 ] 

Sect. 705. Exits. — (a) Every portion of a building shall be provided 
with exits as specified in Part 18. 

(b) Exits from every story shall be so located that no point within the 
story shall be further than one hundred feet from the nearest exit. 

(c) Doorways serving as exits from rooms into a stair or ramp enclosures 
shall have one-way swinging self-closing doors opening in the direction of 
egress. 

fSect. 706. Light and Ventilation.— Rooms used by human beings 
shall be provided with light and ventilation by means of windows or skylights 
or with artificial light and a ventilating system. 

[ fils amended by Ord. 1943, ch. 3 ] 

(60) 



Sees. 707-708 

*Sect. 707. Fire-Extinguishing Apparatus. — (a) Automatic sprin- 
klers or other adequate fire-extinguishing apparatus as approved by the com- 
missioner shall be installed in the following locations: — 

(1) Throughout every unit of occupancy higher than two stories or 
having an aggregate floor area greater than ten thousand square feet. 

(2) In cellars and basements of which the floor area is more than fifteen 
hundred square feet. 

(3) Throughout a building which is occupied wholly or in part as a 
planing mill, box factory, or other wood working establishment, in which 
more than two power-operated wood working machines, other than saws, 
are used. 

(4) Throughout a building which is occupied wholly or in part as a 
mattress factory or used to manufacture, assemble or renovate mattresses 
or stuffed furniture using cotton, silk floss, mohair or other like material 
for packing or stuffing. 

(5) In a building used as a film exchange, or for the manufacture or 
storage of nitro-cellulose pyroxylin products. 

(b) Portable fire-extinguishers, not less than one for every two thousand 
square feet of floor area and at least one in each story, or first aid standpipes 
shall be provided, except as required by chapter one hundred and forty-eight 
of the General Laws and regulations issued thereunder. 

(c) Fire department standpipes and first aid standpipes shall be provided 
in every building more than seventy feet high. 

[ *As amended by Ord. 1943, ch. 3 ] 

fSect. 708. Special Hazards. — (a) Neither apparatus having an 
open flame nor a heater with an enclosed flame shall be installed or operated 
in a dry cleaning establishment or place where volatile flammable liquids 
are used or stored, unless approved by the state fire marshal. 

(b) Rooms in which volatile flammable liquids are used or stored shall be 
enclosed with partitions of not less than one-hour fire-resistive construction 
as specified in Part 22. Doorways in such partitions shall have Class C fire 
doors so equipped as to close automatically in case of fire. 

(c) In a dry cleaning establishment each machine which uses a volatile 
flammable liquid shall have an adequate steam line directly connected to it, 
so arranged as automatically to fill the machine with steam in case of fire 
or explosion therein. 

(d) In dry cleaning establishments and other buildings in which volatile 
flammable liquids are used, sold or stored; 

(1) Type VI construction shall not be used; 

(2) Type IV construction shall not be used more than two stories in 
height or over six hundred square feet in area. 

(e) Rooms in which paint, petroleum or other flammable liquids are used 
or stored otherwise than in unopened containers shall have non-absorbent, 
incombustible floor finish. 

[ \As amended by Ord. 1948, ch. 3 \ 



(61) 



See, 801 



PART 8. 

SPECIAL REQUIREMENTS FOR GROUP F OCCUPANCY 
OFFICES AND COMMERCIAL BUILDINGS. 

Section 

801 — Group F Occupancy: Type, Height, Area. 

802 — Separation of Occupancies. 

803 — Exterior Walls. 

804 — Enclosure of Vertical Openings. 

805 — Exits. 

806 — Light and Ventilation. 

807 — Fire=Extinguishing Apparatus. 



*Section 801. Group F Occupancy: Type, 

Group F shall include such occupancies as — 



Height, Area. — (a) 

Office buildings, restaurants, police and fire stations, museums 



Division 1. 

and libraries. 

Division 2. Wholesale and retail stores, printing plants, factories and 
work shops using materials not highly flammable. 

Division 3. Buildings for the storage or sale of goods not highly flam- 
mable, stables and buildings not on wharves for the storing or handling of 
transient freight. 

Division 4. Wharf buildings for the storage or handling of transient 
freight. 

Division 5. Garages of more than six cars capacity and hangars. 

(b) Buildings or parts of buildings classified for occupancy in Group F 
except those in Division 4 thereof, shall be limited as to type of construction, 
height and area of units, as follows: — 



Type of 
Construction 



Height in 
Stories. 



Maximum Area of Unit in Square Feet Accessible From 



Minimum within 
block Less than 30%, 



30% and less than 
50% of perimeter. 



More than 50% 
of perimeter. 



I 


8 
1 
4 
1 
3 
1 
2 
1 
2 


Not 

10,000 
15,000 
10,000 
15,000 
10,000 
15,000 

6,000 

6,000 

3,000 


hereby limited. 

15,000 

15,000 

15,000 

15,000 

15,000 

15,000 

8,000 

8,000 

5,000 




II 


40,000 


Ill 


Not hereby limited. 
20,000 


IV 


Not hereby limited. 
20,000 


V 


Not hereby limited. 
10,000 


VI 


20,000 
10,000 







Note. — Where areas in 1 story buildings are not hereby limited, the maximum distance 
from any point to an exit from the building shall be 175 lineal feet. 

In garages over six cars Type VI shall not be allowed. 

(02) 



Sees. 801=803 

The maximum area of Type IV units may be increased proportionately 
within the limits given as the number of stories is decreased from the 
maximum. 

(c) The portions of police stations in which not more than ten persons 
may be detained shall be constructed of incombustible materials and shall 
be separated from the remainder of the building, if of combustible materials, 
by a two-hour fire-resistive separation. 

(d) Buildings on wharves, used for storage other than that which is 
incidental to handling water-borne freight, or used for manufacturing or any 
purpose other than such handling, shall be classified in an occupancy group 
according to such use, disregarding their location on wharves. Buildings 
on wharves of pile or other open construction over water, or of filled construc- 
tion behind retaining walls or bulkheads, beside docks wherein vessels may 
be moored, used for handling, namely for assembling, loading, discharging 
and sorting water-borne freight, or for passengers, and of the several types 
of construction shall not exceed in height and area of units of occupancy the 
following limits: — 



Type of Construction. 


Stories. 


Maximum Area of Unit (Square Feet). 


I 


Not hereby limited. 
3 to 7 

2 
3 to 4 

2 

3 

2 

2 


Not hereby limited. 


II 


15,000 


Ill 


120,000 
12,000 


IV 


60,000 
10,000 


V 


60,000 
60 000 







(e) In buildings on wooden wharves, such units of occupancy shall not 
exceed twenty thousand square feet in area. 

(f) The maximum areas provided in this section for buildings of Division 1, 
and for buildings of Divisions 2 and 3 less than six stories in height, may be 
increased fifty per cent if the entire floor area is protected with automatic 
sprinklers. 

[ *As amended by Ord. 1943, ch. 3 ] 

Sect. 802. Separation of Occupancies. — Group F occupancies shall be 
separated from other occupancies, and fire divisions of Group F occupancy 
shall be separated from adjoining fire divisions as specified in Part 13. Two 
tenants shall be separated by partitions of at least one-hour and, in a base- 
ment, at least two-hour fire-resistive rating. 

Sect. 803. Exterior Walls. — (a) Exterior walls or parts of walls, 
except where fronting on a street, which are less than ten feet from a property 
line, shall be of at least two-hour fire-resistive construction and all openings 
therein shall be protected by Class B fire doors or fire windows. 

(63) 



Sees. 803=805 

(b) Every portion of an exterior wall which faces, at a distance of less than 
twenty feet, the further side of a street, or a combustible wall or roof, or an 
unprotected opening in a wall or roof of another building on the same lot, shall 
be of at least two-hour fire-resistive construction, and all openings in such 
portions, except doorways and windows in the first story fronting on a public 
way, shall be protected by Class B fire doors or fire windows. 

(c) The commissioner may waive the requirements of this section, for pro- 
tection of openings in walls, temporarily pending construction on an adjoining 
lot or across a street, provided the owner agrees in a writing recorded in the 
registry of deeds for Suffolk county to comply with the said requirements on 
demand of the commissioner. 

(d) In buildings of Type V construction exterior walls of unprotected 
metal may be considered to meet the requirements of this section for two-hour 
walls. 

*Sect. 804. Enclosure of Vertical Openings. — (a) Elevator shafts, 
ventilating shafts and other vertical openings except stairways and ramps, 
shall be enclosed. 

(b) Ramps for the movement of freight shall be enclosed as specified in 
Part 15 or shall be provided with automatic-closing Class A fire doors which 
will serve as a fire stop between stories. A ramp with such doors shall not be 
counted as a required exit. 

(c) In buildings of Division 1 and in retail stores, stairways and ramps 
other than for freight, serving only basements, first and second stories, need 
not be enclosed. Exit stairways and ramps which pierce only one floor, 
except as provided in the preceding sentence, shall be enclosed in the story 
above or below. Other exit stairways and ramps shall be enclosed in all 
stories in which they occur. 

(d) This section shall not be held to require enclosure of mezzanine floors 
nor of vertical openings in such floors. The provisions of this section shall not 
apply to book stacks of incombustible material in libraries of Type I or Type 
II construction. 

(e) Ramps which are used for the movement of automobiles from one 
story to another, or for a similar purpose, shall be enclosed or shall be provided 
with automatic-closing, Class A fire doors which will serve as a fire stop 
between stories. A ramp with such doors shall not be counted as a required 
exit. 

(f) Doors which are part of an automobile ramp enclosure may be kept 
normally open but shall be so equipped as to close automatically in case of 
fire. 

(g) Mechanical stairways or mechanical conveyors and ramps may be 
installed with manually operated closing devices satisfactory to the com- 
missioner. 

[ *As amended by Ord. 1943, ch. 8 ] 

Sect. 805. Exits. — Every portion of a Group F building except library 
book stacks three levels or less in height shall be provided with exits as 
specified in Part 18. 

(64) 



Sees. 806=807 

*Sect. 806. Light and Ventilation. — Rooms used by human beings shall 
be provided with light and ventilation by means of windows or skylights or 
with artificial light and a ventilating system. 

[ *As amended by Ord. 1943, ch. 3 } 

fSect. 807. Fire=Extinguishing Apparatus.— (a) Automatic sprin- 
klers shall be installed in cellars and basements of which the floor area is more 
than fifteen hundred square feet. "* *" 

(b) Buildings of Divisions 2 and 3, six or more stories in height shall be 
equipped throughout with automatic sprinklers. 

(c) Buildings of Division 4 of Type III, Type IV or Type VI construction 
or on wooden wharves, more than five thousand square feet in area of units, 
and buildings of Type I, Type II or Type V construction on incombustible 
wharves, more than twenty thousand square feet in area, shall be protected 
by automatic sprinklers. 

(d) In buildings more than two stories high either portable fire-extinguish- 
ers, not less than one for every twenty-five hundred square feet of floor area 
and at least one in each story, or first aid standpipes, shall be provided. 

(e) Fire department standpipes and first aid standpipes shall be provided 
in buildings more than seventy feet high. 

(f) Garages shall have automatic sprinklers and other suitable fire-fighting 
apparatus when floor area exceeds ten thousand square feet on any one floor 
or if the height is five stories or more. Hangars shall have approved fire- 
extinguishing apparatus. 

[ \As amended by Ord. 1943, ch. 3 ] 



(05) 



Sec. 901 



PART 9. 

SPECIAL REQUIREMENTS FOR GROUP Q OCCUPANCY: 
COMMERCIAL BUILDINGS OF NON-HAZARDOUS 
OCCUPANCY. 

Section 

901 — Group Q Occupancy: Type, Height, Area. 

902 — Separation of Occupancies. 

903 — Exterior Walls. 

904 — Enclosure of Vertical Openings. 

905 — Exits. 

906 — Light and Ventilation. 

907 — Fire=Extinguishing Apparatus. 

*Section 901. Group G Occupancy: Type, Height, Area. — (a) 

Group G shall include such occupancies as — 

Division 1. Ice, power and pumping plants, cold storage rooms and 
plants, creameries, breweries and other similar buildings. 

Division 2. Factories and workshops using incombustible and non- 
explosive materials. 

Division 3. Buildings for the storage or sale of incombustible and non- 
explosive materials. 

(b) Buildings or parts of buildings classified for occupancy in Group G 
shall be limited as to type of construction, height and area of units, as follows: — 



Type of 
Construction. 



Height in 
Stories. 



Maximum Area of Unit in Square Feet Accessible From 



Minimum within 
block Less than 30%. 



30% and less than 
50% of perimeter. 



More than 50% 
of perimeter. 



I. . 
II. 

Ill 

IV. 

V.. 
VI. 



10,000 

15,000 

15,000 

10,000 

15,000 

15,000 

10,000 

15,000 

15,000 

6,000 

6,000 ' 

3,000 



Not hereby limited. 



15,000 

15,000 

15,000 

15,000 

15,000 

15,000 

15,000 

15,000 

15,000 

8,000 

8,000 

5,000 



40,000 

80,000 
Not hereby limited. 

20,000 

40,000 
Not hereby limited. 

20,000 

30,000 
Not hereby limited. 

10,000 

20,000 

10,000 



Note. — Where areas in 1 story buildings are not hereby limited, the maximum distance 
from any point to an exit from the building shall be 175 lineal feet. 

The maximum area of Type IV units may be increased proportionately 
within the limits given as the number of stories is decreased from the maximum. 
[ *As amended by Ord. 1943, ch. 3 } 
(66) 



Sees. 902=906 

Sect. 902. Separation of Occupancies. — Group G occupancies shall 
be separated from other occupancies, and fire divisions of Group G occupancy 
shall be separated from adjoining fire divisions as specified in Part 13. 

Sect. 903. Exterior Walls. — (a) Exterior walls or parts of walls, 
except where fronting on a street, which are less than ten feet from a property- 
line, shall be of at least two-hour fire-resistive construction and all openings 
therein shall be protected by Class B fire doors or fire windows. 

(b) Every portion of an exterior wall which faces, at a distance of less 
than twenty feet, the further side of a street, or a combustible wall or roof, 
or an unprotected opening in a wall or roof of another building on the same 
lot, shall be of at least two-hour fire-resistive construction, and all openings in 
such portions shall be protected by Class B fire doors or fire windows. 

(c) The commissioner may waive the requirements of this section, for 
protection of openings in walls, temporarily pending construction on an 
adjoining lot or across a street, provided the owner agrees in a writing recorded 
in the registry of deeds for Suffolk county to comply with the said require- 
ments on demand of the commissioner. 

(d) In buildings of Type V construction exterior walls of unprotected 
metal may be considered to meet the requirements of this section for two- 
hour walls. 

*Sect. 904. Enclosure of Vertical Openings. — (a) Elevator shafts, 
ventilating shafts, and other vertical openings, except stairways and ramps 
shall be enclosed. 

(b) Ramps for the movement of freight shall be enclosed as specified 
in Part 15 or shall be provided with automatic-closing Class A fire doors 
which will serve as a fire stop between stories. A ramp with such doors 
shall not be counted as a required exit. 

(c) Stairways and ramps other than for freight which pierce only one 
floor shall be enclosed in the story above or below but such stairways or 
ramps which serve as required exits from one story shall be enclosed in the 
other story. Other stairways and ramps shall be enclosed in all stories in 
which they occur. 

(d) This section shall not be held to require enclosure of mezzanine 
floors nor of vertical openings in such floors. 

(e) Doors which are part of an automobile ramp enclosure may be kept 
normally open but shall be so equipped as to close automatically in case of fire. 

(f) Mechanical stairways or mechanical conveyors and ramps may be 
installed with manually operated closing devices satisfactory to the com- 
missioner. 

[ *As amended by Ord. 1943, ch. 8 ] 

Sect. 905. Exits. — Every portion of a building shall be provided with 
exits as specified in Part 18. 

fSect. 906. Light and Ventilation.— Rooms used by human beings 
shall be provided with light and ventilation by means of windows or skylights 
or with artificial light and a ventilating system. 

[ 1[As amended by Ord. 1943. ch. 3 ) 

(67) 



Sec. 907 

*Sect. 907. Fire=Extinguishing Apparatus. — (a) Automatic sprin- 
klers shall be installed in all cellars and basements, of Division 2 and 3, of 
which the floor area is more than fifteen hundred square feet. 

(b) Automatic sprinklers shall be installed throughout buildings of 
Division 2 or 3, of Type IV construction more than seventy-five hundred 
square feet in area. 

(c) In buildings more than two stories high either portable fire-extin- 
guishers not less than one for every thirty-five hundred square feet of floor 
area and at least one in each story, or first aid standpipes shall be provided. 

(d) Fire department standpipes and first aid standpipes shall be provided 
in buildings more than seventy feet high. 

[ *As amended by Ord. 1943, ch. 3 ] 



(68) 



Sec. 1001 



PART 10. 

SPECIAL REQUIREMENTS FOR GROUP H OCCUPANCY: 
UNLIMITED HABITATIONS AND LARGE DWELL- 
INGS.* 

[ *As amended by Ord. 1943, ch. S ] 
Section 

1001 — Group H Occupancy: Type, Height, Area. 

1002 — Separation of Occupancies. 

1003 — Exterior Walls. 

1004 — Enclosure of Vertical Openings. 

1005 — Exits. 

1006 — Light and Ventilation. 

1007 — Rooms. 

1008 — Fire=Extinguishing Apparatus. 

1009 — Plumbing and Heating. 

fSection 1001. Group H Occupancy: Type, Height, Area. — (a) 

Group H shall include such occupancies as — 

Division 1. Hotels, apartment hotels, dormitories, lodging houses, 
convents, monasteries, and club houses, with sleeping accommodations for 
ten or more persons, or for more than three families, or for more than two 
families above the first story, and without kitchens in the individual apart- 
ments. 

Division 2. Apartment houses accommodating more than three families, 
or more than two families above the first story, and with kitchens in the 
individual apartments. 

(b) Buildings or parts of buildings classified for occupancy in Group H 
and of the several types of construction shall not exceed in height and area 
of units of occupancy the following limits: — 



Type of Construction. 


Stories. 


I 


Not hereby limited. 
5 
3 
3 
3 


II 


Ill 


IV 


VI 





Maximum Area of Unit (Square Feet.) 



Not hereby limited. 

12,000 

8,000 

6,000 

5,000 



Type V construction shall not be used in buildings of Group H. 

(c) Assembly halls in Group H buildings shall be classified in Group A 
or Group B as the case may be, and shall conform to the requirements of this 
code for the group in which they are so classified. 

(69) 



Sees. 1001-1005 

(d) The first floor of buildings more than two thousand square feet in 
area and more than three stories in height shall be of Type I or Type II 
construction. The basement ceilings of other buildings shall be of at least 
one-hour fire-resistive construction. All ceilings of buildings more than two 
thousand square feet in area and three stories or more in height shall be of 
at least one-hour fire-resistive construction. 

(e) Partitions forming separations between adjoining apartments shall 
be of not less than one-hour fire-resistive construction. 

(f) Buildings of Type VI shall not be used for more than four families, 
nor more than two families above the first story. 

[ fAs amended by Ord. 1943, ch. 3 ] 

Sect. 1002. Separation of Occupancies. — Group H occupancies shall 
be separated from other occupancies, and fire divisions of Group H occupancy 
shall be separated from adjoining fire divisions as specified in Part 13. A 
garage of not more than six cars capacity shall be separated from a Group H 
occupancy as specified in Part 12. 

Sect. 1003. uxterior Walls. — (a) Exterior walls or parts of walls, 
o™ej_ . "ronting on a street, which are less than ten feet from a property 

line, st_ ~c; of at least two-hour fire-resistive construction and all openings 
in such walls which are less than seven feet six inches from a property line 
shall be protected by Class B fire doors or fire windows. 

(b) Every portion of an exterior wall which faces, at a distance of less 
than fifteen feet, the further side of a street, or a combustible wall or roof, 
or an unprotected opening in a wall or roof of another building on the same 
lot, shall be of at least two-hour fire-resistive construction, and all openings 
in such portions shall be protected by Class B fire doors or fire windows. 

(c) The commissioner may waive the requirements of this section, for 
protection of openings in walls, temporarily pending construction on an 
adjoining lot or across a street, provided the owner agrees in a writing recorded 
in the registry of deeds for Suffolk county to comply with the said require- 
ments on demand of the commissioner. 

JSect. 1004. Enclosure of Vertical Openings. — (a) Vertical shafts 
and floor openings, except as hereinafter mentioned, shall be enclosed. 

(b) Except as otherwise noted herein, stairways and ramps shall be 
enclosed in all stories in which they occur as specified in Part 15. Stairways 
serving as exits from sleeping rooms shall be enclosed in all stories. Stairways 
serving only basement rooms for the use of the public need not be enclosed. 
Stairways serving only rooms for use of public in the basement, first and 
second story need not be enclosed. Auxiliary stairway within an apartment 
serving only two floors need not be enclosed. 

(c) This section and Part 15 shall not be held to require enclosure of 
mezzanine floors in Group H buildings nor of vertical openings in such floors. 

[ JAs amended by Ord. 1943, ch. 3 ] 

*Sect. 1005. Exits. — (a) Every portion of a Group H building shall 
be provided with exits as specified in Part 18. 

(b) Every apartment of less than four rooms shall have at least one 
exit opening upon a corridor which, has at least two remote exits, or such 

(70) 



Sees. 1005=1006 

apartment shall have two remote exits. Every apartment of four or more 
rooms shall have at least two remote exits. Such exits may open into a 
common corridor which has at least two remote exits. 

(c) Every exit from an apartment shall not be more than fifty feet from 
the nearest exit from the story. 

(d) Corridors which serve as common exits from two or more apartments 
shall have walls of at least one-hour fire-resistive construction. Corridors, 
including their changes in directions and extensions beyond separations serv- 
ing as required egress, shall be at least thirty-six inches wide. If more than 
fifty feet and less than seventy-five feet in length they shall be at least forty- 
eight inches wide. If seventy-five or more feet in length they shall be at 
least sixty inches wide. 

(e) Doors affording access from a stairway to a roof shall not be so locked 
as to prevent egress to the roof in emergency. 

(f) Every stairway and corridor common to two or more apartments 
shall be adequately lighted at all times as determined by the building 
commissioner. 

[ *As amended by Ord. 1943,' ch. S ] 

fSect. 1006. Light and Ventilation. — (a) Kitchens 1 is. a floor 
area more than seventy square feet and dining rooms, within apartments, 
all sleeping rooms and living rooms shall be provided with light and venti- 
lation by means of windows in the exterior walls. The area of windows in 
kitchens shall not be less than one eighth of the floor area thereof, nor less 
than eleven square feet. Windows in toilets or bathrooms shall not be less 
than one eighth of the floor area thereof nor less than six square feet. Win- 
dows shall be arranged to open for ventilation on not less than one half the 
required area. 

(b) Every window required by paragraph fa) of this section shall front 
upon a street, alley or open passageway not less than fifteen feet wide, or upon 
a public park, cemetery, railroad right of way or other similar approved 
open space, or upon a yard or court of the dimensions herein specified. A 
court upon which such a window fronts shall be open to the sky and no cornice, 
balcony, stairway, fire escape or other construction shall encroach upon 
the required open area thereof herein specified. The height of a court shall 
be measured from the sill of the lowest window required to front upon it. 
The width and the horizontal area of such court shall not be less than as 
provided in the following numbered paragraphs (1) to (5), inclusive. 

(1) If the court is open at both opposite ends for its full width and full 
height to a street, alley, park, or other permanently open space, not less 
than fifteen feet wide, or to a yard, it shall be a through court. The least 
width of such court shall be not less than six feet nor less than one tenth its 
length from open end to open end measured along the center line and not 
necessarily in a straight line. The width of such court at any level more 
than fifty feet above the sill of the lowest window required to front upon 
it shall be not less than six feet plus one eighth the excess of such height over 
fifty feet, except a court the length of which is less than five times its least 
width. If windows required by this section face a wall on the opposite 
side of a through court in which windows also required by this section 

(71) 



Sec. 1006 

occur, the width of the court as determined by the foregoing requirements 
shall be increased by fifty per cent. The width of a through court need 
not, however, exceed the width required in this section for an inner court 
of the same height. 

(2) If the court is open at one end for its full width and full height to a 
street, alley, park, or other permanently open space not less than fifteen 
feet wide, or to a yard, it shall be an outer court. The least width of such 
court shall be not less than eight feet nor less than one fourth its horizontal 
length measured along the center line, and not necessarily in a straight line. 
The width of such court at any level more than fifty feet above the sill of the 
lowest window required to front upon it shall be not less than eight feet 
plus one eighth the excess of such height over fifty feet, except a court the 
length of which is less than twice its least width. If windows required by 
this section face a wall on the opposite side of an outer court in which 
windows also required by this section occur, the width of the court as 
determined by the foregoing requirements in this paragraph shall be in- 
creased by fifty per cent. The width of an outer court need not, however, 
exceed the width required in this section for an inner court of the same 
height. 

(3) Every court which is not open at one or both ends as provided for 
an outer court or a through court shall be an inner court. The least width 
of an inner court shall be not less than ten feet. The width of such court at 
any level more than fifty feet above the sill of the lowest window required 
to front upon it shall be not less than ten feet plus one eighth the excess of 
such height over fifty feet. If windows required by this section face a wall 
on the opposite side of an inner court in which windows also required by this 
section occur, the width of the court as determined by the foregoing require- 
ments in this paragraph shall be increased by fifty per cent. The horizontal 
area of an inner court shall be not less than three hundred square feet nor less 
above any floor level than sixty square feet for each story below said level 
served by such court. Every inner court shall be provided with an intake 
for fresh air, consisting of a court, corridor, passageway or ventilating 
duct, of which the area of cross-section below the level of the top of the 
lowest required window shall be not less than one fifteenth the maximum 
required area of the court. Such intake or the required area thereof shall 
be permanently open and unobstructed except for a grille or screen at least 
eighty per cent open at one or both ends and shall extend from the court 
to a street, alley, park, or other permanently open space, not less than 
fifteen feet wide, or to a yard, above the level of the ground thereof. 

(4) Windows required by paragraph (a) of this section may front upon 
an open recess from the street, alley, park, court, yard or other open space 
from which they derive light and ventilation, provided the width of the 
recess is not less than four feet nor less than its horizontal depth, and its 
depth is not more than six feet. A recess from an inner court of width 
less than the required width of the court of which it is a part shall be dis- 
regarded in computing, for the purpose of this section, the area of the court. 

(5) The length of outer courts T-shaped in plan shall be measured 
from the open end to the end of each branch independently. A branch, 

(72) 



Sec. 1006 

open at only one end, of a through court, shall be considered to be a part 
of an outer court of length measured from the nearest open end to the 
closed end of the branch, in determining the width of such branch. Where 
a recess occurs at the closed end of an outer court the length of the court 
shall include the depth of the recess. Adjoining courts which conform 
independently to this section may be combined by omission of dividing 
walls. An inner court between two sections of a through court may be 
disregarded in computing the length of the through court. Other arrange- 
ments of courts shall be measured for the purposes of this section as deter- 
mined by the commissioner with a view to providing for every required 
window light and ventilation substantially as herein specified. 

(6) Courts of exceptional form may be approved by the building 
commissioner if in volume, lighting and ventilating properties they are in 
his opinion the equivalent of the courts above described. 

(c) Every kitchen having a floor area not more than seventy square feet 
within an apartment and every room containing a water closet, shall be 
provided with light and ventilation by means of a window, except as specified 
in paragraph (d) of this section, in an exterior wall or in a ventilating shaft 
or, if such room is immediately under a roof, by a skylight in the roof. 
Such window or skylight shall have an area not less than three square feet 
nor less than one tenth of the floor area of the room, and shall be arranged 
to open for ventilation not less than three square feet nor less than one 
twentieth the floor area of the room. Such windows shall front upon an 
open space or a ventilating shaft of which the width shall be not less than 
three feet and of which the horizontal area shall be not less than fifteen 
square feet. If the height of such space or shaft above the sill of the lowest 
window served is in excess of fifty feet, the width thereof shall be increased 
one half foot and the area eight square feet for every ten feet or fraction of 
such excess. If such ventilating shaft is covered, the covering shall be a 
skylight with openings under the edges thereof on at least three sides equal 
in the aggregate to at least twice the required area of the ventilating shaft. 

(d) Rooms containing water closets need not have windows as specified 
in paragraph (c) of this section if they are provided with adequate artificial 
light and an approved system of mechanical ventilation which will com- 
pletely exhaust the air in the room at least four times per hour. A kitchen 
having a floor area not more than seventy square feet within an apartment 
need not have windows if it is so provided with artificial light, and such 
mechanical ventilation or ventilation by means of a ventilating exhaust 
duct with at least one square foot net area of cross-section independent of 
ducts from other rooms to a point above the roof. A kitchen ventilated as 
provided in this paragraph or by a ventilating shaft shall have a permanent 
opening of adequate size for fresh air which may, however, be drawn from 
other rooms in the apartment. 

(e) Dining rooms in hotels, dining rooms common to more than one 
family, kitchens serving such dining rooms and other kitchens and rooms 
for eating purposes except those within apartments, shall be provided with 
light and ventilation as specified for kitchens and dining rooms respectively 

(73) 



Sees. 1006=1007 

in paragraphs (a) and (b) of this section or shall have artificial light and an 
approved system of mechanical ventilation providing not less than four 
complete changes of air per hour. 

(f) The boundary line of a lot on which a building is to be erected subject 
to the provisions of this section, unless it is a common boundary between 
such lot and a street, alley, public park, cemetery, railroad right of way or 
other similar, permanently open space, not less than fifteen feet wide shall 
be a boundary to an adjacent court or ventilating shaft required by this 
section as though a wall without windows were erected on such line. If 
there is, appurtenant to such lot, an easement for light and air over a portion 
of an adjoining lot, in terms which assure that the easement will remain in 
force and effect so long as any windows require it for light and ventilation 
under the provisions of this code, and duly recorded in the registry of deeds 
for Suffolk county, the portion subject to such easement may be considered 
to be part of such lot for the purposes of this section. No building or 
structure shall be erected in such manner as to reduce the light and ventila- 
tion in a building on the same lot subject to the provisions of this section 
below the requirements thereof, nor shall a lot line be moved by sale of 
land or otherwise so as to permit such reduction by a building on an adjoining 
lot. 

(g) In a residence district, as defined in chapter four hundred and eighty- 
eight of the acts of nineteen hundred and twenty-four, a building of Divi- 
sion 2 upon a lot which abuts on only one street shall have a yard at the 
rear. Such yard shall be open and unobstructed above the level of the sills 
of windows opening thereon required by this section, shall extend the full 
width of the lot, and shall have a depth, measured from the rear of the build- 
ing to the rear line of the lot or, if an alley or open passageway lies at the 
rear of the lot, to the middle line of such alley or passageway, not less than 
twelve feet nor less than one fourth the height of the building above the 
sill of the lowest window required to front upon such yard. If the rear line 
of such lot is other than a straight line the required yard shall have an area 
not less than twelve feet times the width of the lot at the rear of the building 
and the building shall be so disposed at the rear as to leave a yard having 
approved continuity with the yards of adjoining lots. The provisions of 
this paragraph shall not apply to a lot which abuts at the rear upon a rail- 
road right of way, cemetery, park or other permanently open space, not 
less than fifteen feet wide. The Boston zoning law (chapter four hundred 
and eighty-eight of the acts of nineteen hundred and twenty-four) also 
contains provisions relative to yards. 

(h) Every room containing a water closet compartment shall have 
adequate means for lighting at all times. 

[ ]As amended by Ord. 1943, ch.3] 
JSect. 1007. Rooms. — (a) In every apartment of an apartment 
house or apartment hotel, at least one room shall have a floor area not less 
than one hundred and twenty square feet. However, every kitchen in such 
apartment shall be not less than six feet wide nor less than forty-eight square 
feet in area. Every room containing a water closet shall be not less than 
thirty-three inches wide and shall have a floor area not less than fifteen square 

(74) 



Sees. 1007=1009 

feet. Every other room in such apartment, except closets and vestibules, 
shall have not less than seventy square feet of floor area. 

(b) Rooms in apartments, except closets, shall be at least eight feet high 
in half their required area, an average of at least six feet high in the remainder 
of the required area, and not less than four feet high at any point within 
the required area. 

(c) If the walls or floor of a sleeping room or living room are in contact 
with the ground, the portions thereof in such contact shall be waterproofed 
as specified in Part 29 or damp proofed in an approved manner, and the 
interior finish of such portions of the walls of such rooms shall be furred 
with impervious material. Not more than thirty per cent of the area of the 
walls enclosing such a room shall be in contact with the ground. 

(d) The floor of every room containing a water closet shall be of tile, 
terrazzo, linoleum or other impervious material with a base of similar ma- 
terial around the walls at least four inches high. No water closet shall be 
enclosed in woodwork placed close about the fixture. The walls of every 
room containing a water closet shall extend to the ceiling. 

[ XAs amended by Ord. 1943, ch. 8 ] 

*Sect. 1008. Fire Extinguishing Apparatus. — (a) Automatic 
sprinklers shall be installed in cellars, basements, workrooms, shops, store 
rooms and kitchens, in buildings of Type I and Type II construction more 
than six stories high, and in other buildings more than three stories high. 

(b) First aid standpipes, as specified in Part 30, or portable extinguishers, 
at least one for every twenty-five hundred square feet of floor area and at 
least one in each story, shall be provided in buildings more than five thousand 
square feet in area or more than six stories high. 

(c) Fire department standpipes and first aid standpipes shall be installed 
in buildings more than seventy feet high. 

[ *As amended by Ord. 1943, ch. 3] 

Sect. 1009. Plumbing and Heating. — (a) Every apartment in an 
apartment house and every apartment of two or more rooms in an apartment 
hotel shall have within it at least one room containing a water closet and 
devoted exclusively to use as a bathroom or toilet room. One such room 
shall be accessible from every sleeping room without passing through another 
sleeping room. In every such apartment there shall be a lavatory or sink 
with running water. 

(b) Every apartment in a hotel and every apartment in an apartment 
hotel not included in paragraph (a) of this section shall have within it at 
least one room containing a water closet, as specified in paragraph (a) of this 
section, or shall have access in common with other apartments to such a room 
in the same story or in the next story above or below, by means of a common 
corridor. Where the number of sleeping rooms without a water closet within 
the apartment exceeds six in a story, separate toilet rooms for men and for 
women shall be provided in the same story, plainly marked, and shall con- 
tain one water closet for every nine sleeping rooms or fraction of nine. Com- 

(75) 



Sec. 1009 

mon bathrooms shall have means for securely locking the door on the inside. 
Every such room shall contain at least one lavatory or sink with running 
water. 

(c) In every apartment of an apartment house or apartment hotel which 
is not adequately heated from a central heating plant, at least one room 
with a floor area not less than one hundred and twenty square feet shall have 
a chimney, as specified in Part 21, with a separate flue not less than eight 
inches in diameter, or a common flue not less than twelve inches in diameter, 
with a thimble at least six inches in diameter about six feet above the floor. 

(d) In buildings more than three stories high, every boiler room or room 
containing a central heating plant shall be separated from the rest of the 
building by at least a two-hour separation as specified in Part 13. 



(76) 



Sees. 1101-1102 



PART 11. 

SPECIAL REQUIREMENTS FOR GROUP I OCCUPANCY: 
LIMITED HABITATIONS AND SMALL DWELLINGS.* 

[ *As amended by Ord. 1943, ch. 3 ] 
Section 

1101 — Group I Occupancy: Type, Height, Area. 

1 102 — Separation of Occupancies. 

1103 — Exterior Walls. 

1104 — Enclosure of Vertical Openings. 

1105 — Exits. 

1106 — Light and Ventilation. 

1 107 — Fire=»Extinguishing Apparatus. 

fSection 1101. Group I Occupancy: Type, Height, Area. — (a) 

Group I shall include such occupancies as — 

Division 1 . Dwellings accommodating not more than three families, nor 
more than two families above the first story. 

Division 2. Dormitories, lodging houses, clubs, convents and monasteries, 
with sleeping accommodations for less than ten persons. 

(b) Buildings or parts of buildings classified for occupancy in Group I 
shall be limited as to type of construction, height and area of units, as 
follows : — 



Type of Construction. 


Stories. 


Maximum Area of Unit (Square Feet). 


I 


Not hereby limited. 
5 
3 
3 
3 


Not hereby limited. 


II 


12,000 


Ill 


8,000 


IV 


6,000 


VI 


5,000 







(c) The basement or cellar ceiling of all Group I buildings, more than 
three stories in height, shall be of not less than one-hour fire-resistive con- 
struction. Boiler rooms in Type IV and Type VI construction with more 
than one family above the first story shall be separated by walls and ceilings 
of not less than one-hour separation with any openings in the separation to be 
Class B fire doors and windows. 

[ \As amended by Ord. 1943, ch. 3 } 

Sect. 1102. Separation of Occupancies. — Group I occupancies shall 
be separated from other occupancies, and fire divisions of Group I occupancy 
shall be separated from adjoining fire divisions as specified in Part 13. A 
garage of not more than six cars capacity may be constructed as part of a 
Group I building as specified in Part 12. 

(77) 



Sees. 1103=1107 

Sect. 1103. Exterior Walls. — (a) Exterior walls or parts of walls, 
except where fronting on a street, which are less than five feet from a property- 
line shall be of at least two-hour fire-resistive construction and all openings 
therein shall be protected by Class B fire doors or fire windows. 
[ *As amended by Ord. 1943, ch. 3 ] 

fSect. 1104. Enclosure of Vertical Openings. — (a) Elevator shafts, 
ventilating shafts and other vertical openings, including stairways, except 
stairway in a single family occupancy, shall be enclosed. 

(b) Where two or more stairways are required as exits at least one shall 
be enclosed in all stories in which it occurs. Stairways which pierce more than 
three floors shall be enclosed. 

(c) In stairway enclosures not more than three stories high, the doors in 
stories other than the basement or cellar need not be fire doors if they are of 
wood not less than one and one half inches thick. 

[ fAs amended by Ord. 1943. ch. 3 ] 

JSect. 1105. Exits. — Group I buildings more than three stories in height, 
and Group I buildings in which the area of any floor, except the first floor, 
exceeds fifteen hundred square feet, shall have at least two stairways or 
ramps, one of which shall be interior and enclosed, and every Group I build- 
ing where each dwelling does not have its own stairway within its own apart- 
ment shall have two stairways, one of which shall be enclosed. A single 
family house may have one stairway if it is less than three stories in height. 
[ JAs amended by Ord. 1943, ch. 3 and Ord. 1954, ch. 7 } 

§Sect. 1106. Light and Ventilation. — (a) Rooms of Group I build- 
ings used for eating, living or sleeping purposes, shall be provided with light 
and ventilation by means of windows. The space on which such windows 
shall open shall not be less than as specified in Part 10 for similar windows in 
Group H buildings. 

(b) Kitchens and rooms containing water closets shall be lighted and 
ventilated as provided for similar rooms of Group H buildings in Part 10. 
[ §As amended by Ord. 1943, ch. 3 ] 

iJSect. 1107. Fire=Extinguishing Apparatus. — (a) Automatic sprin- 
klers shall be installed in cellars, basements, workrooms, sloops, storerooms and 
kitchens other than in apartments, in buildings more than six stories high. 

(b) First aid standpipes, as specified in Part 30, or portable fire-extin- 
guishers, at least one for every twenty-five hundred square feet of floor area, 
and at least one in each story shall be provided in Group I buildings more than 
five thousand square feet in area or more than six stories high. 

(c) Fire department standpipes and first aid standpipes shall be installed 
in buildings more than seventy feet high. 

(d) This section shall not apply to buildings of Division 1, referred to in 
section eleven hundred and one. 

[ || As amended by Ord. 1943, ch. 3 ] 



(78) 



Sec. 1201 



PART 12. 

SPECIAL REQUIREMENTS FOR GROUP J OCCUPANCY: 
MISCELLANEOUS STRUCTURES. 

Section 

1201 — Group J Occupancies: Type, Height, Area. 

1202 — Separation of Occupancies. 

1203 — Exterior Walls. 

1204 — Exits. 

1205 — Aisles and Seating. 

1206 — Light and Ventilation. 

1207 — Fire=Extinguishing Apparatus. 

1208 — Floor Finish. 

*Section 1201. Group J Occupancies: Type, Height, Area. — (a) 

Group J shall include such occupancies as — 

Division 1. Garages for six cars or less. 

Division 2. Tanks, towers, advertising signs and similar structures. 

Division 3. Amusement park structures, reviewing stands, grand stands, 
and similar structures. 

(b) Garages for six cars or less, not exceeding two stories in height nor 
thirteen hundred square feet in floor area, may be of any type of construction 
except Type VI. Garages, for three cars or less, one story in height and not 
exceeding six hundred and fifty square feet in area, may be of Type VI 
construction. 

(c) Structures of Division 2, erected on the roof or on the facade of a 
building in the first or second fire zone, shall be constructed with incom- 
bustible materials, except water tanks, flag poles, isolated signs flat against 
an exterior wall not more than twenty square feet in area, and isolated signs 
projecting from an exterior wall; provided, that such projecting signs have a 
frame of incombustible material, that the combustible material in such pro- 
jecting signs is no more combustible than wood, that no part of such combus- 
tible materia] is nearer an exterior wall than fifteen inches, and that the surface 
area of such combustible material is not more than thirty-five square feet on 
any face and not more than seventy square feet in the aggregate, except that 
the surface area of such combustible material, if the nearest point thereof is 
eighteen or more inches from all exterior walls, may be more than thirty-five 
square feet on a face and more than seventy square feet in the aggregate if 
the building commissioner certifies on the application for the permit to erect 
such sign that in his opinion the spread of fire therefrom is no more likely 
than from a projecting sign having an incombustible frame and two wooden 
faces each thirty-five square feet in area the nearest point of which wood is 
fifteen inches from the nearest exterior wall. 

(d) Reviewing stands and grand stands may be constructed of masonry, 
reinforced concrete, steel or wood or any combination thereof. When con- 
structed, except for the seats, of incombustible materials, the size shall not 

(79) 



Sees. 1201=1202 

hereby be limited. When the structure below the deck is constructed of 
incombustible material, and the decking is of wood or other combustible 
material, the horizontal distance from front to back shall not exceed one 
hundred feet. When the entire structure is constructed of wood or other 
combustible material, the horizontal distance from front to back shall not 
exceed fifty feet. 

(e) Amusement park structures of the open or skeleton framed type 
may be constructed of any type of construction and are not hereby limited in 
height and area. 

(f) Amusement park structures of the enclosed type, shall be limited as 
to type of construction, height and area of units, as follows: — 



Type of Construction. 


Height. 


Area 

of Unit. 

(Square Feet.) 


Feet. 


Stories 


I 


Not herebv limited. 


Not hereby limited. 


II 


75 
55 
35 
35 
35 


■1 
3 

2 
2 
2 


15,000 


Ill 


10,000 


IV 


10,000 


V 


5,000 


VI 


5,000 







(g) Amusement park structures of enclosed type used as places of assembly 
shall be classified in Group A or Group B in accordance with the definitions 
thereof. 

(h) The maximum areas provided in this section may be increased fifty 
per cent if the entire floor area is protected by automatic sprinklers. 
[ *As amended by Ord. 1943, ch. 3 and Ord. 1950, cfi. 6 ] 



Sect. 1202. Separation of Occupancies. — (a) When a garage of 
size and arrangement to accommodate not more than two cars is constructed 
as part of a Group H or Group I building, the walls and ceilings of the garage 
shall be of not less than one-hour fire-resistive construction. When a garage 
to accommodate more than two but not more than six cars is constructed as 
part of a Group H or Group I building, the walls and ceiling of the garage 
shall be of not less than three-hour fire-resistive construction. Openings in 
such walls shall be protected by Class B fire doors or by fire windows. A 
garage to accommodate not more than six cars shall be separated from other 
occupancies and from adjoining fire divisions as specified in Part 13. 

(b) In a separation between a garage of Group J occupancy and another 
occupancy there shall not be more than one opening, and the sill thereof 
shall be raised one foot above the garage floor. There shall be no opening 
from a garage directly into a living room, sleeping room or kitchen. 

(80) 



Sees. 1203=1208 

Sect. 1203. Exterior Walls. — Exterior walls or parts of walls, of Group J 
structures, except where fronting on a street, which are less than five feet 
from a property line or less than ten feet from, another building on the same 
lot, shall be of not less than one-hour fire-resistive construction and all open- 
ings therein shall be protected by Class B fire doors or fire windows, and such 
walls which are less than three feet from a property line or less than six feet 
from another building on the same lot, shall be of at least two-hour fire-resistive 
construction and all openings therein shall be protected by Class B fire doors 
or fire windows, except that in garages for three cars or less of Type V con- 
struction, such walls may be of unprotected metal. 

Sect. 1204. Exits. — (a) Reviewing stands, grand stands and similar 
structures shall be provided with exits not less than four feet wide nor less 
than one foot in width for each three hundred persons or fraction thereof 
served. Exits shall have not less than seven feet in clear height nor be more 
than sixty feet apart. 

(b) Where the space under a grand stand, reviewing stand or similar 
structure is used for any purpose other than ingress and egress, the required 
exits through this space shall be enclosed by walls, floors, and ceilings of 
not less than one-hour fire-resistive construction. 

(c) Amusement park structures, other than grand stands or similar 
structures, of either open or enclosed type shall be provided with exits as 
required for Group B occupancy in Part 4. 

Sect. 1205. Aisles and Seating. — Reviewing stands, grand stands 
and similar structures having more than twenty rows of seats shall have 
transverse aisles not over sixty feet apart leading to exits. Transverse 
aisles shall have a clear width not less than thirty inches nor less than one 
foot for ever}' three hundred persons or fraction thereof served. Where 
separate seats are not provided or marked off, a width of eighteen inches 
shall be considered one seat in computing the required width of aisles and 
exits. 

*Sect. 1206. Light and Ventilation. — Amusement park structures 

shall be provided with light and ventilation sufficient to avoid dangerous or 

unhealthful conditions as may be required by the commissioner. They shall 

be lighted by artificial light sufficiently for safe egress. 

[ *As amended by Ord. 1943, ch. 3 ] 

Sect. 1207. Fire=Extinguishing Apparatus. — • Fire-extinguishing ap- 
paratus shall be provided in buildings and structures of Group J where 
the fire hazard, in the judgment of the commissioner, is commensurate with 
that for which such apparatus is specified in buildings of other groups. 

Sect. 1208. Floor Finish. — Garages shall have non-absorbent incom- 
bustible floor finish. 



(81) 



Sec. 1301 



PART 13. 
SEPARATION OF OCCUPANCIES. 

Section 

1301 — Multiple Occupancies. 

1302 — Separations. 

*Section 1301. Multiple Occupancies. — (a) A >fire division, whether 
occupying the whole or a part of a building, shall be limited as to type of 
construction, height and area as provided in Parts 3 to 12, inclusive, according 
to its principal occupancy. 

(b) Adjoining fire divisions in a building shall be separated by a separation 
at least as fire-resistive as required by Table A, section thirteen hundred and 
two. 

(c) A fire division may contain two or more units of different occupancies, 
and every such unit shall be limited as to height above the ground and as to 
area as provided in Parts 3 to 12, inclusive, according to its occupancy and 
the type of construction of the building. 

(d) Adjoining units of different occupancy in a fire division shall be 
separated by a separation at least as fire-resistive as specified in Table A, 
section thirteen hundred and two. Space within a unit of occupancy used 
for a purpose or process customarily incidental to that occupancy and under 
the same management and control shall not be considered a separate unit 
of occupancy unless the floor area of such space exceeds one tenth the area 
of the fire division in which it is located; but garage use shall not so be con- 
sidered incidental. 

(e) Every unit of occupancy shall conform to the provisions of Parts 3 
to 12 of this code for the group and division in which it is classified. 

(f) Two adjoining fire divisions may be of different types of construction 
subject to the following limitations: 

(1) Construction required to be of Type I shall not be supported 
wholly or in part by construction of any other type. 

(2) Construction required to be of Type II shall not be supported by 
construction other than of Type I or Type II. 

(3) Construction required to be of Type III shall not be supported by 
construction other than of Type I, Type II or Type III. 

(4) Construction required to be of Type IV shall not be supported by 
construction other than of Type I, Type II, Type III or Type IV. 

(5) Construction required to be of Type V shall not be supported by 
construction other than of Type I, Type II or Type V. 

(82) 



Sees. 1301=1302 

(6) Construction required to be of Type VI shall not be supported by- 
construction other than of Type I, Type II, Type III, Type IV or Type VI. 

(g) Separations, as specified in this code, may be vertical, horizontal, 
or inclined, depending upon the relative position of the portions of the building 
to be separated, and shall consist of a system of walls, partitions, floors or 
other construction of such materials and construction and so arranged as to 
provide a complete, secure and continuous fire-break of the required fire- 
resistive rating between the portions of the building separated. 

(h) A building more than three stories high used on first floor or basement, 
for commercial use and adapted for more than two families above the first 
floor shall be equipped with automatic sprinklers throughout that portion 
used for commercial use when, in the judgment of the commissioner, public 
safety demands such protection. 

[ *As amended by Ord. 1948, ch. 4 ] 

fSect. 1302. Separations. — ■ (a) Separations between units of occu- 
pancy within a fire division and between fire divisions of a building shall be 
classified, each classification being designated in Table A of this section by 
the letter or figure s}^mbol set against it, having the following significance: 

A — means absolute separation. 
4 — means four-hour separation. 
3 — ■ means three-hour separation. 
2 — means two -hour separation. 
1 — means one-hour separation. 
N — means no separation required. 

(b) An absolute separation shall provide in all its parts effective fire- 
resistance of not less than four-hour rating as specified in Part 22 and shall 
have no openings. 

(c) A four-hour separation shall provide effective fire-resistance of not 
less than four-hour rating as specified in Part 22. Openings in the walls 
of such separations shall be protected on each side thereof by automatic - 
closing Class A fire doors as specified in Part 22. The sum of the areas of 
such openings in one story shall not exceed one third the area of the separating 
wall and no single opening shall have a greater area than one hundred square 
feet. 

(d) A three-hour separation shall provide effective fire-resistance of not 
less than three-hour rating as specified in Part 22. Openings in the walls 
of such separations shall be protected on each side thereof by automatic - 
closing Class B fire doors as specified in Part 22. The sum of the areas of 
such openings in one story shall not exceed one third the area of the separating 
wall and no single opening shall have a greater area than two hundred square 
feet. 

(e) A two-hour separation shall provide effective fire-resistance of not 
less than two-hour rating as specified in Part 22. Openings in the walls of 
such separations shall be protected on one side thereof by automatic-closing 
Class A fire doors as specified in Part 22. The sum of the areas of such 

(83) 



Sec. 1302 

openings in one story shall not exceed one third the area of the separating 
wall and no single opening shall have a greater area than two hundred square 
feet. 

(f) A one-hour separation shall provide effective fire-resistance of not 
less than one-hour rating as specified in Part 22. Openings in the walls of 
such separations shall be protected on one side thereof by automatic -closing 
Class B fire doors as specified in Part 22. 

(g) Walls which form separations between fire divisions shall be fire 
walls as specified in Part 14. Such walls, whether bearing or non-bearing, 
shall be solid masonry not less than eight inches thick or reinforced concrete 
not less than six inches thick. Openings in fire walls shall have fire doors on 
both sides. 

(h) The commissioner may waive in part the requirements of this section 
for the protection of openings less than two square feet in area subject to 
such conditions as he shall in each case specify. 

(i) A fixed fire window, as specified in Part 22, may be considered equiva- 
lent to one Class B fire door in the walls of separations, but two such windows 
shall not be substituted as equivalent to two doors in an opening where two 
fire doors are required. 

(j) Table A, 

(1) For required separations between different unit occupancies in one 
fire division read above the zigzag line. Exception : For separation re- 
quirements between units of occupancy of Group J, Division 1 Occupancy, 
and units in the same fire division of Group H or Group I Occupancy see 
Section 1202, Part 12. 

(2) For required separations between fire divisions read below the zigzag 
line. 

Separations between adjoining fire divisions of Type I, Type II, and 
Type V construction shall be as listed. If either of two contiguous fire 
divisions is of Type III, Type IV, or Type VI construction the provisions 
of the Table shall be modified in accordance with the following: 

The symbol of four hour separation shall be construed to require 
absolute separation, and the other separation symbols shall be con- 
strued to require one hour more than that indicated in the Table. 

In the following table ordinates and coordinates are designated by the 
letters and numbers used in this Code indicating various occupancies. The 
requirements for separation between fire divisions and unit occupancies are 
indicated by the number or letter which appears at the intersection of the 
ordinate and coordinate representing any two contiguous fire divisions or 
unit occupancies. See paragraph (a) for significance of said numbers and 
letters. 



(84) 



Sec* 1302 



Table A, (l)— Required Separations Between Different 
Occupancies in One Fire Division. 
(Above Zigzag Line.) 



Group. 



A 


B 


C 


Dl 


D2 


El 


E2 


Fl 


F2 


F3 


F4 


Fo 


Gl 


G2 


G3 


HI 


H2 


11 


12 


N 
4 


2 


2 
1 


3 
3 


3 
2 


3 
4 


3 
4 


3 
2 


3 
2 


3 
3 


3 
3 


3 

4 


3 
3 


3 
2 


3 
2 


3 
1 


3 
1 


3 

1 


3 

1 


3 


4 
4 
4 


2 
4 
4 


2 
4 
4 


3 


2 
3 


4 
4 

4 


4 
4 
4 


1 
3 
1 


2 

3 
2 


2 

3 
2 


2 
3 
3 


4 
4 
4 


3 
3 
3 


2 

3 
2 


2 
3 
2 


1 
3 
1 


1 
3 
1 


N 
3 
1 


X 

3 
1 


2 
4 


2 


A 


A 


4 


4 


A 


3 


2 


3 


3 


3 


3 


3 


3 


3 


3 


3 


3 


3 


3 


A 


A 


4 


4 


A 


3 


3 


2 


2 


2 


o 


3 


3 


2 


2 


3 


3 


3 


3 


4 


3 


3 


4 


3 


3 


3 


3 


X 


X 


X 


3 


3 


X 


X 


X 


N 


N 


X 


4 


3 


3 


4 


4 


3 


3 


3 


3 


X 


X 


3 


3 


X 


X 


1 


1 


1 


1 


4 


4 


3 


4 


4 


3 


3 


3 


3 


3 


X 


3 


3 


1 


1 


1 


1 


1 


1 


4 
4 


4 
4 


3 
4 


4 

4 


A 
A 


3 

o 
O 


3 
3 


3 
3 


3 
3 


3 
3 


3 
3 


3 


3 
3 


1 

3 


1 
3 


1 
4 


1 
4 


1 

4 


1 
4 


3 


4 


4 


4 


4 


A 


3 


3 


3 


3 


3 


3 


3 


3 


3 


3 


3 


3 


3 


3 


4 


4 


3 


4 


3 


3 


3 


3 


3 


3 


3 


3 


3 


2 


X 


1 


1 


1 


1 


4 

4 


4 
3 


3 
3 


4 
4 


3 

3 


3 
4 


3 
4 


3 
3 


3 
3 


3 
3 


3 

3 


3 
4 


3 
3 


2 
3 


3 


1 


1 

X 


1 
X 


1 

X 


3 


4 


3 


3 


4 


3 


4 


4 


3 


3 


3 


3 


4 


3 


3 


3 


3 


3 


X 


X 


4 


3 


3 


4 


3 


4 


4 


3 


3 


3 


3 


4 


3 


3 


3 


3 


3 


2 


X 


4 


3 


3 


4 


3 


4 


4 


3 


3 


3 


3 


4 


3 


3 


3 


3 


3 


2 


2 


4 


4 


4 


4 


4 


3 


3 


3 


3 


3 


3 


3 


3 


3 


3 


3 


3 


2 


2 



Jl 



A 

B. 

C. 

Dl 

D2 

El 

E2 

Fl 

F2 

F3 

F4 

Fa 

Gl 

G2 

G3 

HI 

H2 

II. 

12. 

Jl 



13 



Table A, (2) — Required Separations Between Fire Divisions. 

(Below Zigzag Line.) 

[ "fvls amended by Ord. 1943, ch. 4 ] 



(85) 



Sec. 1401 



PART 14. 
WALLS AND PARTITIONS. 

Section 

1401 — Definition of Walls for Use or Function. 

1402 — General Requirements for Walls. 

1403 — Lateral Support of Walls. 

1404 — Classification of Walls for Type of Construction. 

1405 — Reinforced Concrete Walls. 

1406 — Masonry Walls. 

1407 — Bond in Masonry. 

1408 — Lateral Support of Masonry. 

1409 — Masonry Piers. 

1410 — Beam Supports on Masonry Walls. 

1411 — Masonry Chases, Recesses, Corbels and Lintels. 

1412 — Masonry Foundation Walls. 

1413 — Parapet Walls. 

1414 — Use of Existing Masonry Walls. 

1415 — Masonry Veneer. 

1416 — Steel Frame Walls. 

1417 — Wooden Frame Walls. 

*Section 1401. Definition of Walls for Use or Function.— (a) Walls 
and partitions shall be classified for use or function as follows: — 

(1) A bearing wall is a wall which supports a floor, roof or other load 
in addition to its own weight. 

(2) A non-bearing wall is a wall which supports no load other than its 
own weight. 

(3) An exterior wall is a wall separating the interior from the exterior 
of a building, marking the boundary or extent thereof which may be and 
usually is exposed to the weather on one side. 

(4) An interior wall is a wall wholly within a building and protected 
from the weather. 

(5) A party wall is a wall used or adapted for use in common as a 
part of two buildings. A party wall may be either bearing or non-bearing- 

(6) A fire wall is an interior wall, bearing or non-bearing, forming 
part of a separation between two fire divisions of a building, as provided 
in Part 13. 

(7) A partition is an interior wall, bearing or non-bearing, not over 
one story in height, the chief function of which is to separate two rooms 
of a story. A partition in one story may be supported by a bearing 

partition in the story below. 

(8) A foundation wall is a foundation in the form of a wall, either 
exterior or interior; that portion of the exterior bearing wall of a building 
which is below the grade of adjoining ground. 

(86) 



Sees. 1401=1402 

(9) A retaining wall is a wall of which the chief function is to resist 
the lateral displacement of liquid, granular or other materials. It may- 
be either bearing or non-bearing, exterior or interior. 

(10) A curtain wall is an exterior, non-bearing wall more than one 
story high and not supported at each floor level, which is laterally stayed 
either by masonry piers or by the structural frame of the building. 

(11) A panel wall is an exterior, non-bearing wall not over one story 
high, or supported at each floor level. 

(12) An enclosure wall is an interior wall, bearing or non-bearing, 
which encloses a stairway, elevator shaft or other vertical opening. 

[ *As amended by Ord. 1943, ch. 4 1 

fSect. 1402. General Requirements for Walls. — (a) Walls shall 
have the resistance to fire and to the spread of fire required of them in Parts 3 
to 13, inclusive, and Part 15 of this code, but may be finished, except on the 
outside of exterior walls and within enclosures of vertical openings, with 
wooden or other combustible wainscoating, insulating or acoustical material. 
In Type III buildings, there shall be no concealed air spaces between such 
finish and the wall. In Type V buildings such material shall be protected 
from fire on both sides by sheet metal or its equivalent. In Type IV or 
Type VI buildings every hollow space in walls shall be firestopped at floor 
and ceiling. 

(b) Bearing walls shall be so supported and constructed as to be stable 
and to support their weight and the loads which may be placed upon them 
without exceeding the stresses allowed for the materials of which they are 
constructed as provided in Parts 23 to 29, inclusive. Exterior walls, party 
walls, bearing walls and fire walls and their vertical or lateral supports shall 
be capable of resisting the pressure of the wind applied to either side. 

(c) Court walls shall be of such fire-resistive construction and shall have 
such limitations as to openings and the protection of openings as are specified 
for exterior walls in Parts 3 to 12, inclusive. 

(d) Exterior bearing walls pi buildings of Type I, Type II, Type III and 
Type IV shall be of four-hour fire-resistive construction as provided in sec- 
tions one hundred and twenty-six to one hundred and twenty-nine, inclusive, 
of Part I. Where such exterior walls are required, in Parts 3 to 12, inclusive, 
to be without openings the panels or non-bearing portions of the walls shall 
afford resistance of four-hour rating to the spread of fire. Where openings 
in such exterior walls are required, in Parts 3 to 12, inclusive, to be protected 
with fire doors or fire windows, the panels or non-bearing portions of the walls 
shall afford resistance of two-hour rating to the spread of fire. Where the 
openings in such exterior walls are unrestricted, panels or non-bearing portions 
of such walls shall be of incombustible construction, excepting, that sash, 
window frames, blinds, shutters, screens, doors, door frames, door and window 
trims, their architraves, pilasters and entablatures may be of wood or other 
not easily inflammable material; and in buildings outside the fire limits isolated 
pilasters and building cornices may be of wood or some other not easily 
inflammable material. Furthermore, architectural surfaces, trimmings, 
plaques, panels or the like of wood covered with metal or other incombustible 

(87) 



Sees. 1402=1405 

material may be applied to the exterior of buildings, and there may be in- 
corporated in the masonry backing the necessary wooden grounds for their 
attachment, or wooden grounds may be applied to masonry wall if embedded 
in mortar. Metal cornices and the like may be applied to wooden outriggers 
and suitable grounds. 

(e) In buildings with combustible floors, doorways required to have fire 
doors shall have incombustible thresholds the full thickness of the wall and 
doors in their closed positions, and the space thereunder shall be filled solid 
with masonry. Thresholds may be flush with the floor. 
[ jAs amended by Ord. 1943, ch. 4 ] 

Sect. 1403. Lateral Support of Walls. — (a) Walls of any type or 
construction may be considered to have lateral support where anchored or 
secured: — 

(1) To intersecting walls of equal or better fire-resistance. 

(2) To buttresses or piers. 

(3) To the floors, roof and framing. 

Sect. 1404. Classification of Walls for Type of Construction. — (a) 

Walls, including partitions, shall be classified for type of construction as 
follows: — 

(1) Reinforced concrete. 

(2) Masonry. 

(3) Steel frame. 

(4) Wooden frame. 

(b) Any wall which does not fall readily into one of the classifications of 
this section shall be assigned thereto by the commissioner according to its 
pertinent characteristics. 

Sect. 1405. Reinforced Concrete Walls. — (a) Reinforced concrete 
walls may be used for any use or function • described in section fourteen 
hundred and one. 

(b) Reinforced concrete walls other than foundation walls shall be sup- 
ported upon foundations of concrete or masonry or upon construction of 
masonry, reinforced concrete or structural steel the metal of which, except 
as otherwise provided in section fourteen hundred and eleven, shall have pro- 
tection against fire of at least the rating required for the wall itself, and not 
less than two-hour fire-resistive protection. Reinforced concrete walls shall 
not be supported upon wood except wooden piles or other approved under- 
water construction of wood. 

(c) The pertinent provisions of Part 26 shall apply to walls of reinforced 
concrete. 

(d) Reinforced concrete bearing walls shall have a thickness of at least 
one twenty-fifth the height or length between supports, whichever is the lesser 
dimension. 

(e) Foundation walls of reinforced concrete shall be not less than eight 
inches thick. 

(88) 



Sees. 1405=1406 

(f) Non-bearing walls of reinforced concrete shall have a thickness of at 
least one sixtieth of the height or length between lateral supports, whichever 
is the lesser dimension, and shall not be thinner than three inches. Reinforced 
concrete beams which serve in part as walls shall conform to the requirements 
for non-bearing walls. 

(g) Party and fire walls of reinforced concrete shall be at least six inches 
thick. 

(h) Walls of reinforced concrete may be covered with a veneer of masonry 
or other material adequately supported but such veneer shall not be con- 
sidered to be a part of the wall for the purposes of this section. 

(i) No chase or recess shall be cut or formed in a reinforced concrete wall 
so as to impair its stability, or to reduce the minimum thickness to less than 
four inches. 

(j) Where structural steel beams or other metal members frame into 
exterior, party, fire or enclosure walls of reinforced concrete, the ends shall 
have protection against fire of the rating specified for the wall. Where wooden 
joists, beams or other combustible members frame into such walls, the ends 
shall be separated from the opposite side of the wall and from such members 
framing into the opposite side of the wall by not less than four inches of con- 
crete. In buildings of Type III, Type IV or Type VI construction party 
walls and fire walls shall extend through the roof as provided in section 
fourteen hundred and thirteen. 

(k) Exterior and bearing walls of reinforced concrete shall be anchored 
to the floor and roof construction as specified in Parts 16 and 17. 

*Sect. 1406. Masonry Walls. — (a) Masonry may be used for walls of 
any use or function described in section fourteen hundred and one. Specifica- 
tions for masonry in this chapter shall also apply to plain concrete. 

(b) Masonry walls and piers, other than foundation walls, shall be sup- 
ported upon foundations of concrete or masomy, or upon construction of 
masonry, reinforced concrete or structural steel the metal of which, except as 
otherwise provided in section fourteen hundred and eleven, shall have pro- 
tection against fire of at least the rating required for the wall itself, and not 
less than two-hour fire-resistive protection. Masonry walls and piers shall 
not be supported upon wood except wooden piles or other approved under- 
water construction of wood, but this provision shall not apply to fire stopping 
and nogging. 

(c) Exterior bearing walls of masonry shall have a thickness of at least 
one sixteenth the height or length between lateral supports in the top story 
of a building and at least one twentieth such height or length in stories other 
than the top, whichever is the lesser dimension. Masonry exterior bearing 
walls supporting the walls of Type V or Type VI buildings shall be not less 
than eight inches thick. 



(89) 



Sec. 1406 

(d) Exterior bearing walls of masonry shall have at least the thicknes s 
given in the following tables: 

Table A: Exterior Bearing Walls of Masonry for Group A, B, C, E, F, 

Q, J Occupancy. 

Note. — Hollow masonry units may be used in walls of the thickness given only on the top 
four stories. Minimum thickness of walls is given in inches. 



Story. 




Height 


of Wall in Stories 






8. 


7. 


6. 


5. 


4. 


3. 


2. 


1. 


Eighth 


12 
12 
12 
16 
16 
16 
20 
20 
20 


12 
12 
12 
16 
16 
16 
20 
20 


12 
12 
12 
16 
16 
16 
20 


12 
12 
12 
16 
16 
16 


12 
12 
12 
16 
16 


12 
12 
12 
16 


12 
12 
12 




Seventh 




Sixth 




Fifth 

Fourth 


— 


Third 

Second 


— 


First 


12 


Basement 


12 







Table B: Exterior Bearing Walls of Masonry for Group D, H, I 

Occupancy. 

Note. — For special provisions with respect to single-family, Group I occupancy, see the 
following Table C. 



Story. 




Height 


of Wall in Stories 


. 




8. 


7. 


6. 


5. 


4. 


3. 


2. 


1. 


Eighth 


12 
12 
12 
12 
12 
16 
16 
16 
16 


12 
12 
12 
12 
12 
16 
16 
16 


12 
12 
12 
12 
12 
16 
16 


12 
12 
12 
12 
12 
16 


12 
12 
12 
12 
12 


12 
12 

12 
12 


8 
12 
12 












Fifth 




Fourth 




Third 








First 


8 




12 



(90) 



Sees. 1406=1407 

Table C: Exterior Bearing Walls of Masonry for Group I Occupancy, 
Single-Family Dwellings Not Over Three Stories High, Supporting 
Floors Not Over Twenty Feet in Span. 





Story. 


Height of Wall in Stories. 




3. 


2. 


1. 


Third 


8 

8 

12 

12 


8 

8 

12 








First 


8 




s 







(e) Interior bearing partitions of masonry, supporting not more than one 
floor and a roof shall have a thickness of at least one twentieth the height or 
length between lateral supports, whichever is the lesser dimension, and at 
least six inches. Such partitions, not over one story high, supporting stairs, 
stair landings, platforms, a mezzanine floor, or the like, shall have a thickness 
of at least one twentieth the height or length between lateral supports, which- 
ever is the lesser dimension, and at least three and one half inches. Other 
interior bearing walls of masonry shall have at least the thickness required 
in this section for masonry exterior bearing walls. 

(f ) Bearing party walls of masonry shall be solid not less than twelve 
mches thick. Non-bearing party walls and bearing or non-bearing fire walls, 
of masonry shall be solid not less than eight inches thick. 

(g) Exterior masonry panel walls shall be not less than three and one half 
'inches thick. Panel walls more than four feet high, and curtain walls, of 

masonry shall be not less than eight inches thick. Panel or curtain walls of 
metal or fire-resisting, impervious material may be backed up with masonry 
at least two inches in thickness. 

(h) Non-bearing masonry partitions and enclosure walls shall have a 
thickness of at least one forty-fifth the height or length between lateral 
supports, whichever is the lesser, and at least three inches. 

(i) The minimum thickness specified in this section for masonry walls, 
except as otherwise provided in this paragraph, shall be exclusive of unbonded 
veneer, plaster or other covering on either face of the wall. The minimum 
thickness specified in this section for non-bearing partitions and enclosure 
walls shall be inclusive of plaster which is at[least one half inch thick on either 
or both sides, and when the masonry beneath the plaster is at least three 
inches thick. 

[ *As amended by Ord. 1943, ch. 4 ] 

fSect. 1407. Bond in Masonry. — (a) Brick walls shall be bonded 
with at least one full header, every other brick in every sixth course, on both 
faces and the interior of the walls. 



(91) 



Sees. 1407=1408 

(b) In homogeneous masonry walls of stone, bond stones shall be uni- 
formly distributed and shall have a cross-section not less than ten per cent 
of the area of the wall. 

(c) In homogeneous masonry walls of structural clay tile or of solid or 
hollow concrete or gypsum blocks or of similar masonry units, unless all the 
units are the full thickness of the wall, the two faces of the wall shall be 
bonded together through the wall, by varying the thickness of units in alter- 
nate courses so that the blocks will overlap across the wall not less than three 
and one half inches. 

(d) Walls of structural clay tile, concrete blocks or similar masonry 
units, faced with brick, in which the backing is bonded as required for the 
material of which it is built and the brick facing is bonded to the backing as 
required in a brick wall, shall be considered to have the strength and stability 
of a homogeneous wall of the same total thickness of the weaker material. 

(e) A wall of stone, brick, structural clay tile, concrete blocks or other 
masonry units faced with stone ashlar bonded to the wall as herein provided, 
shall be considered to have the strength and stability of a homogeneous wall 
of the same total thickness of the weaker material. In order so to be con- 
sidered a part of the wall, the ashlar facing shall be laid in a full bed of mortar, 
shall be not less than three and one half inches thick and bond stones shall be 
uniformly distributed in all or at least in alternate courses, not less than 
seven and one half inches thick, nor less than four inches thicker than the 
remainder of the facing, and constituting not less than twenty per cent of the 
area of the wall. 

(f) Brick, stone or block facing may be considered to be bonded to back- 
ing of plain or reinforced concrete when the facing, with all the provisions 
for bond required for a facing backed with masonry, is laid in advance of the 
pouring of concrete, and the concrete is poured in direct contact with the 
facing, embedding the header brick or bonding units. 

(g) Masonry walls covered with a veneer not bonded to the wall as pro- 
vided for a facing in this section shall be considered to have a thickness equal 
to that of the wall exclusive of the veneer. 

(h) Hollow walls of brick, laid with every alternate brick in every other 
course on each side of the wall a full header, or any equivalent bond, may be 
used where walls of structural clay tile may be used. 

[ 1[As amended by Ord. 1943, ch. 4 } 

JSect. 1408. Lateral Support of Masonry. — (a) Masonry bearing 
walls, exterior walls, and other masonry walls, which depend upon inter- 
secting walls for lateral support shall be bonded to such walls at intersections 
and corners by having each unit if other than brick alternately overlap by at 
least one half the thickness of the wall at the intersection, and if of brick 
have each alternate brick overlap by half the length of the brick, or a group 
of not over six bricks overlap in alternating groups at least half the thickness 
of the wall. 

(b) Masonry walls which depend upon anchorage to the frame of a build- 
ing for lateral support shall be tied to the frame by suitable anchorage ap- 
proved by the commissioner. 

(92) 



Sees. 1409=1411 

(c) Exterior and bearing walls of masonry shall be anchored to the floor 
and roof construction as specified in Part 16. 

[ JAs amended by Ord. 1943, ch. 4 ] 

Sect. 1409. Masonry Piers. — (a) In walls with openings such that 
the portion of wall between openings constitutes a pier, such portion of wall 
shall be computed and constructed as required for piers. The height of 
such a pier, with a continuous wall above and below the openings shall be 
taken as the height of the openings. 

(b) When the clear horizontal distance between piers in masonry walls 
exceeds ten feet they shall be considered isolated piers. 

(c) Isolated piers shall be built of solid units, for which hollow units 
filled with concrete shall not be substituted. The unsupported height of 
isolated piers shall not exceed twelve times their least dimension. 

Sect. 1410. Beam Supports on Masonry Walls. — (a) Joists, beams 
and other structural members shall not bear directly on hollow walls or walls 
of hollow units, but shall be supported on a sufficient number of courses of 
solid units or equivalent concrete or a metal plate or grillage sufficient to 
distribute the load to the webs and shells in such manner as not to exceed 
the allowable unit stress. 

(b) Where structural steel beams or other metal members frame into 
exterior, party, fire or enclosure walls of masonry, the ends shall have pro- 
tection against fire of the rating specified for the wall. Where wooden joists, 
beams or other combustible members frame into such walls the ends shall be 
separated from the other side of the wall and from members framing into the 
other side of the wall by not less than four inches of masonry. 

*Sect. 1411. Masonry Chases, Recesses, Corbels and Lintels. — 

(a) There shall be no chases in masonry bearing or exterior walls eight 
inches or less in thickness or within the required area of a pier, and no chase 
in a bearing, exterior or fire wall or pier shall reduce the thickness thereof 
to less than eight inches. No horizontal or diagonal chase shall be allowed 
except subject to the limitations and conditions provided in this section for 
recesses. 

(b) Recesses for stairways, elevators or other purposes may be made in 
masonry bearing, or exterior walls, but in no case shall the walls at such 
points be reduced to less than the thickness required in the fourth story. 
Such walls of reduced thickness shall have such additional lateral support 
as may be necessary. Recesses in masonry bearing or exterior walls for 
radiators and similar purposes, shall have not less than eight inches of masonry 
at the back. Such recesses shall be not more than eight feet in length unless 
the wall at the back may be considered a curtain or panel wall, and they 
shall then be arched over or spanned with lintels. 

(c) No chases or recesses shall be permitted in fire or party walls that will 
reduce the thickness below the minimum specified in this code. 

(d) Chases and recesses may be built as provided in this section, but 
shall not be cut in masonry walls of hollow masonry units or in hollow walls 
of brick. 

(93) 



Sees. 1411=1412 

(e) Chases shall be fire-stopped at floor and ceiling levels. 

(f) Corbels may be built in masonry walls to furnish bearing for floors 
or roof but such corbels shall not project from the face of the wall more than 
one fourth the thickness of the wall nor more than one fourth the height of the 
corbel. Corbels shall be built with solid masonry units and thoroughly 
bonded to the wall. No corbel in a masonry wall less than twelve inches 
thick shall be used for the support of a floor or roof. 

(g) Chimneys constructed of the same material as that of the wall, and 
lined as provided in Part 21, may be supported by corbels of which the 
projection is not more than one fourth the height nor more than the thickness 
of the wall, but no chimney shall be supported on a corbel from a wall less than 
twelve inches thick. 

(h) Openings in masonry walls for doorways and windows shall have 
well buttressed arches or lintels of incombustible material. Structural or 
reinforcing steel in such lintels shall have protection against fire of the rating 
required for the wall, but not less than two-hour fire-resistive protection; 
except that the masonry over an opening may be supported by a steel plate, 
angle or similar member not fireproofed on the under side, if the width of the 
opening does not exceed six feet in bearing walls and ten feet in non-bearing 
walls, or if the member so unprotected is itself supported, at intervals not 
exceeding six feet in bearing walls and ten feet in non-bearing walls, from a 
beam or other adequate structure which has the required protection. 
[ *As amended by Ord. 1943, ch. 4] 

fSect. 1412. Masonry Foundation Walls. — (a) Masonry foundation 
walls shall conform to the requirements for foundations of Part 29. 

(b) Sand lime brick, gypsum tile and cinder concrete poured in place 
shall not be used in foundation walls nor as part of the required thickness 
thereof. Wood shall not be used in the foundations of permanent structures 
except as provided in Part 29. 

(c) Rough or random rubble stone masonry without level beds shall not 
be used for foundation walls more than ten feet high or supporting buildings 
more than forty-five feet high. 

(d) Masonry foundation walls shall be at least as thick as the wall sup- 
ported, and not less than the following thickness: — ■ 

Minimum Thickness (Inches) of Masonry Foundation Walls. 

Concrete 8 

Solid masonry (except rubble) . . . ... . . . 8 

Hollow masonry .12 

Rubble masonry . ... 20 

(e) Foundation walls and retaining walls, which depend upon a floor or 
superimposed structure for resistance to overturning shall not be back-filled 
until so supported or properly shored to the satisfaction of the commissioner. 
Walls damaged by premature back-filling shall be removed and replaced 
if so required by the commissioner. 

(94) 



Sees. 1412-1415 

(f) Masonry-foundation walls supporting wood shall be carried at least 
eight inches above adjoining ground and shall be effectually sealed to prevent 
moisture from reaching the wood through capillary action. 

(g) Masonry in foundation walls shall be laid in cement mortar or cement- 
lime mortar. 

[ |As amended by Ord. 1943, ch. 4 ] 

Sect. 1413. Parapet Walls.— (a) In buildings of Type III, Type IV 
or Type VI construction not more than forty-five feet in height, party walls 
and fire walls shall extend through the roof not less than twelve inches, and in 
such buildings more than forty-five feet in height, not less than thirty inches. 
Masonry walls extending above the roof shall have a coping of incombustible 
material. 

(b) In such buildings, exterior walls required by Parts 3 to 12, inclusive, 
to be of four-hour fire-resistive construction without openings, shall extend 
above the roof, as provided in this section for party walls. 

JSect. 1414. Use of Existing Masonry Walls. — An existing masonry 
wall may be used in the construction of a post-code building and in the repair, 
alteration or enlargement of a building providing it meets the requirements of 
this code, and is structurally sound or can be made so by reasonable repairs. 
Existing masonry walls which are structurally sound but which are of insuffi- 
cient thickness for their proposed use shall be strengthened by an addition of 
similar material not less than eight inches in thickness laid in mortar of re- 
quired proportions. Foundations and lateral supports shall be provided as 
required for newly constructed walls under similar conditions. Such addi- 
tions or linings shall be thoroughly bonded to the existing masonry by toothings 
bonded with the new masonry and built solidly into openings cut in the old 
masonry at least four inches deep. Such toothings shall be distributed uni- 
formly throughout the wall and shall aggregate in vertical cross-sectional area 
not less than fifteen per cent of the total vertical area of the wall or lining. If 
the existing wall is covered with plaster or other covering that might impair 
the bond of the lining, such covering shall be stripped off and the masonry 
cleaned. The repair, lining, or other strengthening of an existing masonry 
wall to be used in the construction of a post-code building and in the repair, 
alteration or enlargement of a building shall be in every respect satisfactory to 
the commissioner and subject to such conditions as he may in any case pre- 
scribe. 

[ tAs amended by Ord. 1943, ch. 4 ] 

Sect. 1415. Masonry Veneer. — (a) Unbonded masonry veneer may 
be used as a covering for a wall of any type of construction with or without air 
space. It shall not be regarded as a structural part of the wall or as contribut- 
ing to its strength or stability, but it may serve as protection from the weather 
and where built without hollows or air spaces it may serve as protection for 
metal against fire. Gypsum shall not be used in veneer exposed to the 
weather. 

(b) Masonry veneer shall be anchored to the backing, if of masonry, by 
headers or bond units, built at least three and one half inches into the back- 
OS) 



Sees. 1415-1417 

ing, uniformly distributed, and having an area at least one fortieth the area 
of the wall, or by approved non-corrodible metal ties spaced not further apart 
than one foot, or three times the thickness of the veneer except that masonry 
veneer of thin flat stones on edge shall be anchored every twelve inches in all 
horizontal joints by non-corrodible anchors not less than one quarter inch in 
least dimension dowelled at least one inch into the top of veneer stones and 
well secured to the backing. 

Sect. 1416. Steel Frame Walls. — (a) Walls framed with structural 
steel may be used for any of the functions described in section fourteen 
hundred and one. 

(b) The frames of exterior steel frame bearing walls shall have fire pro- 
tection of the rating specified for the exterior bearing walls of the building 
according to its type of construction in sections one hundred and twenty-six 
to one hundred and thirty, inclusive, of Part 1 and in Parts 3 to 12, inclusive. 

(c) The frames of interior steel frame bearing walls shall have fire protec- 
tion as required for structural steel columns in Parts 16 and 17. 

(d) The frames of steel frame party walls shall have four-hour fire-resistive 
protection. 

(e) The frames of steel frame curtain and panel walls shall have fire pro- 
tection of the rating specified for such walls in section fourteen hundred and 
two and in Parts 3 to 12, inclusive. 

(f) The frames of steel frame enclosure and fire walls shall have fire 
protection of the rating specified for the walls in Parts 3 to 13 inclusive and 
in Part 15. 

(g) The steel frames of walls required by this section to be protected 
against fire shall not be supported upon wood or other combustible material 
nor upon metal with less protection than is required for such frames. 

(h) The frames of steel frame exterior walls and other walls exposed to 
moisture shall be protected from rusting. 

(i) Solid or hollow non-bearing partitions of steel frame and plaster shall 
have a total thickness not less than one sixtieth the height between lateral 
supports, nor less than two inches. The plaster of hollow partitions shall be 
not less than three quarters inch thick. Vertical steel frame members shall be 
at least equivalent to twenty-four gage steel channels of a depth not less than 
half the thickness of the partition spaced not over twenty-four inches on 
centers. 

(j) Except as otherwise specified in this section steel frame bearing or 
non-bearing walls may have frames of unprotected steel and panels of incom- 
bustible materials. Steel frame walls, bearing or non-bearing, with panels of 
combustible materials, may be used only where wooden frame walls are 
allowed by this code, except that in buildings of Type V, unprotected steel 
frame walls may have panels containing a layer of combustible insulating 
material between sheets of steel or equally protective covering. 

*Sect. 1417. Wooden Frame Walls. — (a) Wooden frame walls shall 
not be used for exterior walls except in buildings of Type VI construction nor 
for interior bearing walls except in buildings of Type IV or Type VI con- 

(96) 



Sec. 1417 

struction. Wooden frame walls shall not be used for party walls, fire walls, 
enclosure walls required to have greater than one-hour fire resistance, nor 
for walls where incombustible materials are specified. Wooden frame walls 
shall not be used for foundation walls, nor for bearing partitions in basements 
or cellars. 

(b) Non-bearing wooden frame partitions may be used in buildings of 
Type I, Type II, and Type V, in occupancy of Group F and Group G only, 
solely for the purpose of sub-dividing space occupied by one tenant, provided 
that the space so divided shall be separated from any other tenant in the 
same story by partitions of fire-resistive quality as required by the particular 
conditions. 

Non-bearing wooden stud partitions covered on both sides with three 
quarter inch thick plaster on incombustible lath may be used in buildings of 
Type I and Type II for Groups H and J occupancy, solely for the purpose of 
sub-dividing apartments or similar space occupied by one tenant, provided 
that such partitions shall not exceed five hundred lineal feet within a single 
floor area, separated from the rest of the story by partitions of fire-resistive 
quality as required for the particular conditions. 

Nothing in this paragraph shall be construed to allow wooden frame 
partitions in Type I, Type II, and Type V buildings where fire-resistive 
partitions of other materials for egress, enclosures or vertical openings, or 
separations are required elsewhere in this code. 

(c) Wooden frame exterior walls shall have posts, sills, and girts not 
smaller than three and five eighths by five and five eighths inches. When the 
studs are continuous throughout two stories they shall be of one piece, the girts 
shall be replaced by a ledger board not less than fifteen sixteenths by five and 
five eighths inches housed into the studs. Studs shall be no smaller than one 
and five eighths by three and five eighths inches. Dimensions of members in 
this paragraph are actual net dimensions. 

Posts shall be well braced the full story height, and walls shall be framed to 
them by a stud-sized brace attached to the post just below the girt and running 
in the wall at an angle not more than sixty degrees from the vertical, attached 
at the other end to the girt or sill. These braces shall be horizontally braced 
at the corner post at least once in each story, and the studs which they inter- 
sect shall be well fastened above and below the brace. Posts and girts 
shall be mortised, tenoned, and pinned at each floor level or connected by 
approved metal fasteners which provide equal rigidity. The tenons shall be 
not less than one inch in thickness and the full height of the girt. 

Where a ledger board replaced a full girt the space behind the ledger board 
shall be fire stopped with at least one and five eighths inch lumber cut between 
the studs. In wooden stud exterior bearing walls more than one story high? 
the studs shall be not over sixteen inches apart on centers, and shall be bridged 
at least once at mid-height. In one story walls studs shall be spaced not over 
twenty inches apart on centers, and need not be bridged. At intersections, 
between such walls and interior partitions, studs shall be well blocked, making 
what is commonly known as solid corners. Wall plates shall consist, either 

(97) 



Sec. 1417 

of two layers of wood not less than one and five eighths by three and five eighths 
inches, each, or of one layer of wood not less than three and five eighths by 
three and five eighths inches. At openings in bearing walls, studs shall be 
doubled or have a minimum section of three and five eighths by three and 
five eighths inches and the heads of openings shall be trussed. 

Posts in one and two story walls shall be in one piece — ■ in three stories they 
may be spliced once in their length, just above the second or third floor girt. 
Girts and caps may be spliced not oftener than once in twelve feet. Such 
splices shall be made by halving the piece of wood with a lap of at least eight 
inches. The lap shall be securely pinned or spiked. In two-piece caps the 
minimum length of pieces shall be the full length of the wall or twelve feet. 
Joints shall be broken with at least twelve inches overlap. If studs are 
spaced farther apart than indicated in this paragraph they shall be classed as 
wooden columns, girts and caps framing on them shall be classed as wooden 
beams, and they shall all meet the requirements of section twenty-five hundred 
and five and twenty-five hundred and six. 

(d) Wooden stud bearing partitions shall have studs not less than one and 
five eighths by three and five eighths inches supported upon a girder or upon a 
sole plate not less than one and five eighths inches thick. The partition plate 
shall be not less than one and one half inches thick. Studs of a partition 
in an upper story over a partition below shall rest upon the plate of the lower 
partition and not upon the ends of the floor beams. Studs of wooden frame 
bearing partitions shall be bridged at least once at mid-height and studs 
supporting a floor shall be not more than sixteen inches apart on centers. 
Studs shall be doubled beside openings in partitions, and the heads of such 
openings shall be trussed or framed sufficiently heavy to carry the load. 
Wooden stud bearing partitions shall not be used to support more than a roof 
and three floors and in buildings three stories or more in height shall have 
one-hour fire-resistive rating. If studs are spaced farther apart than indicated 
in this paragraph, they shall be classed as wooden columns and the caps over 
them shall be classed as wooden beams and they shall both meet the require- 
ments of sections twenty-five hundred and five and twenty-five hundred and 
six unless in the category of the following: In one story habitations, where 
height from sill to plate does not exceed nine feet, the studs may be one and 
five eighths by two and five eighths inches, plate may be two pieces of one and 
five eighths by two and five eighths inches or one piece of two and five eighths 
by three and five eighths inches, sills may be two and five eighths by five and 
five eighths inches and corner posts may be blocked studs. 

(e) Hollow wooden frame walls and partitions shall be firestopped at 
floor and ceiling levels. Bearing partitions shall be firestopped the full height 
between ceiling and floor above. Firestopping shall consist of incombustible 
materials or of wood not less than one and one half inches thick. 

(f) Exterior wooden frame bearing walls shall be covered on the outside 
with wood boarding nailed to the studs or with other approved material 
equally effective in stiffening the frame of the building. Boards shall be not 
less than three quarters inch thick unless a weather boarding is used, in which 
case it shall have an average thickness of at least five eighths inch. Each 

(98) 



Sec. 1417 

board shall have at least two nails to each stud. Stucco, masonry veneer 
and any material composed principally of gypsum shall not be considered a 
satisfactorjr substitute for boarding on exterior wooden frame walls. 

(g) Any other style of wall construction which provides stability, rigidity 
and fire-resistance equal to that of the walls specified in this section, as dis- 
closed in tests prescribed by the commissioner and satisfactorily passed, may 
be used where wooden frame walls are allowed. 

[ *As amended by Ord. 1943, ch. 4, Orel 1953, ch. 7, and Ord. 1955, ch. 2 ] 



(99) 



Sees. 1501-1502 



PART 15. 
PROTECTION OF VERTICAL OPENINGS. 

Section 

1501 — Protection of Vertical Openings. 

1502 — Trap Doors. 

1503 — Enclosure of Vertical Openings. 

1504 — Floor Construction within Enclosures. 

1505 — Openings for Ventilation in Ventilating Shafts. 

1506 — Ventilating Ducts. 

1507 — Use of Enclosures. 

*Section 1501. Protection of Vertical Openings. — (a) Where 
an opening in only one floor is required to be enclosed by provisions of Parts 3 
to 12, inclusive, or by Part 18, it shall be enclosed either in the story above 
or in the story below, or protected by a trap door in such manner as to resist 
the spread of fire from one story to the other. Where a series of openings in 
two or more floors, required to be enclosed, are enclosed in one shaft, they 
shall be enclosed in all stories. A required exit shall not be closed by a trap 
door, except as otherwise provided in Part 18. The exterior walls of buildings 
are excluded from the provisions of this part, except as specifically provided 
in section fifteen hundred and three. 

(b) Openings in floors which are not provided with trap doors and are 
not enclosed in the story above, shall be protected by an adequate railing 
at least thirty inches high. Openings in roofs, unless covered by trap doors 
or skylights, shall be protected by an adequate railing or parapet at least 
thirty inches high. 

[ *As amended by Ord. 1943, ch. 4] 

*Sect. 1502. Trap Doors. — (a) A trap door in a floor or roof shall 
be able to support its own weight and a concentrated load of two hundred 
pounds; and unless protected by a curb not less than six inches high or by a 
railing, shall be able to support a live load equal to that of the floor or roof 
in which it is placed. The requirements of this section shall not apply to 
stage construction in a theatre. A trap door in a floor shall be arranged to 
close automatically in case of fire in a manner satisfactory to the commissioner. 

(b) In buildings of Type I and Type II construction a trap door shall 
not exceed six feet in either dimension, and shall have fire resistance equiva- 
lent to that of a Class A fire door as specified in Part 22. 

(c) In buildings of a type of construction other than Type I or Type II, 
trap doors shall be of the construction required for the floor or roof, except 
that a trap door in a ceiling required to have fire resistance shall be equivalent 
in fire resistance to a Class A fire door as specified in Part 22 and shall not 
exceed six feet in either dimension. 

(d) The commissioner may waive in part or modify the requirements of 
this section for protection of openings less than four square feet in area subject 
to such conditions as he shall in each case specify. 

(100) 



Sec. 1503 

*Sect. 1503. Enclosure of Vertical Openings. — (a) In buildings 
of Type I, Type II or Type III construction, the required enclosure of a 
floor opening shall have two-hour fire-resistive rating. 

(b) In buildings of Type IV construction, except as otherwise provided 
in this section, the required enclosure of a floor opening shall have not less 
than one-hour fire-resistive rating. In such buildings four stories or more 
in height and in such buildings three stories in height other than of Group H 
or Group I occupancy, such enclosures shall also be of incombustible ma- 
terials. In buildings of Type IV construction more than three stories high 
an enclosure about both stairs and elevator shall have not less than two-hour 
fire-resistive rating. 

(c) In buildings of Type V construction floor openings, if enclosed, shall 
be enclosed with incombustible materials. 

(d) In buildings of Type VI construction, except as otherwise provided 
in this section, the enclosure of a floor opening where required, shall have 
not less than one-hour fire-resistive rating, and this provision shall apply 
to the inside face of that portion of an exterior wall which forms part of such 
an enclosure as well as to an interior wall. 

(e) Combustible wainscoting, insulating or acoustical material may be 
attached to the walls of enclosures provided for in this section, but not within 
the enclosure, as specified in Part 14. 

(f) Doorways in enclosures only about passenger elevators shall be pro- 
tected by Class C fire doors or doors of incombustible materials in which 
glass shall be wire glass. Doorways in other enclosures of vertical openings 
shall be protected, in enclosures required to have two-hour fire-resistive rating 
by Class B fire doors and in enclosures required to have one-hour rating by 
Class C fire doors, except as otherwise provided in Parts 3 to 12, inclusive. 
Window openings in required enclosures shall be protected by fire windows. 
Openings for ventilation in required enclosures shall be protected as pro- 
vided in section fifteen hundred and five. Other openings in required en- 
closures shall be protected as the commissioner shall in each case specify. 

(g) In required enclosures of floor openings, fire windows shall be fixed or 
automatic-closing; doors shall be self-closing or automatic-closing, except 
access doors for repairs which shall be kept closed and locked, and except 
doors in enclosures only about passenger elevators. 

(h) The enclosure of chutes and dumb-waiters not exceeding four square 
feet in area need not have fire-resistive protection if constructed of metal 
not thinner than sixteen gauge if in Type I, Type II, or Type V construction. 
If in Type III, Type IV, or Type VI construction they shall be protected by 
not less than one-hour fire-resistive enclosure and Class B automatic-clos- 
ing doors. 

(i) Every elevator shaft and stairway enclosure, except dumb-waiter 
enclosures and enclosures in the interior of a building which do not serve the 
top story, shall be ventilated at the top by an opening to the outside air 
not less in area than one per cent of the area of the shaft. In addition, each 
such shaft shall have at the top means for emergency ventilation in the form 

(101) 



Sees. 1 §03=1506 

of windows or sk}'lights with thin plain glass, with metal screen beneath, 
or wire glass, or in other approved form, not less in area than one quarter the 
area of the shaft. 

[ *As amended by Orel. 1943, ch. 4 ] 

Sect. 1504. Floor Construction within Enclosures. — Where the 
enclosure of floor openings is required by the provisions of Parts 3 to 12, inclu- 
sive, or of this part to be of a construction more fire-resistive than the floors 
of, the buildings or where such enclosure is required to be of incombustible 
materials, any portion of a floor of the building which shall form part of the 
enclosure, as when the walls thereof are offset, in successive stories, shall be 
of materials and construction equivalent in fire resistance to that required 
for the walls. 

fSect. 1505. Openings for Ventilation in Ventilating Shafts. — 

(a) Openings for ventilating purposes in enclosures, larger than one square 
foot in area, except as otherwise provided in this section shall be protected 
in one of the six following methods : — 

(1) Louvres or dampers, which shall close by gravity or be held open 
by a fusible link so placed as to permit them to close in the case of fire. 

(2) Openings into a shaft or duct used exclusively to exhaust the air 
from two or more stories may be protected by louvres of incombustible 
material which close by gravity, like a check valve, to prevent reversal 
of the air current. 

(3) Openings into a shaft or duct used exclusively to supply air to two 
or more stories of a building may be protected by louvres which close by 
gravit} r , like a check valve, to prevent reversal of the air current. 

(4) Openings in a ventilating shaft, connected with branch ducts at 
least as long as twelve times the larger transverse dimension of the duct 
need not have additional protection. 

(5) An opening for ventilating exhaust in a shaft enclosure when 
connected to a duct without openings in other stories, leading to a point 
above the roof level, need not have the protection of automatic-closing 
louvres or dampers. 

(6) An opening for the supply of air to a ventilated space which is 
connected by means of a duct without openings in other stories to a fan, 
plenum chamber or other source of air supply, need not have the protection 
of automatically closing louvres or dampers. 

[ fAs amended by Ord. 1943. ch. 4 ] 

Sect. 1506. Ventilating Ducts. — (a) Ventilating ducts in all buildings 
shall be of incombustible materials, but may be lined with fibrous insulating 
or sound deadening material which has been chemically treated, if necessary, 
so that it will not by itself support combustion. Horizontal offsets of vertical 
ducts shall be protected in Type I and Type II buildings by at least one-hour 
fire-resistive construction of incombustible materials. 

( b) The combustible material of partitions and floors through which sheet 
metal ventilating ducts pass shall be kept at least one inch from the metal or be 

(102) 



Sees. 1506=1507 

protected by not less than one half inch of plaster or one quarter inch of 
asbestos board or other incombustible material of equal insulating value. 
Openings between sheet metal ventilating ducts and combustible floor con- 
struction through which they pass shall be fire stopped with incombustible 
material. 

Sect. 1507. Use of Enclosures. Except as otherwise specifically pro= 
vided, no limitation is imposed in this chapter upon the shape or size of the 
enclosure in any story of a vertical opening, but the area within a stairway 
shall not be used for storage or manufacturing, or within any enclosure for 
other than the purpose or purposes for which the vertical opening was con- 
structed, but this provision shall not be held to prevent the placing of electrical 
cabinets, piping, fire extinguishing apparatus and the like, in vertical enclosures 
in such manner as shall not interfere with its required use. A corridor serving 
as a passageway to two remote exits from a story shall be separated from such 
exits, if enclosed, by the enclosure thereof. 



(103) 



Sees, 1601=1602 



PART 16. 

FLOOR CONSTRUCTION. 

Section 

1601 — Floor Construction. 

1602 — Type I: Fireproof Floor Construction. 

1603 — Type II: Semi=Fireproof Floor Construction. 

1604 — Type III : Heavy Timber Floor Construction. 

1605 — Type IV: Light Wooden Floor Construction. 

1606 — Type V: Metal Frame Floor Construction. 

1607 — Type VI: Wooden Frame Floor Construction. 

1608 — Ratproofing. 

Section 1601. Floor Construction. — The floor construction in all 
buildings shall conform to the requirements of other chapters of this code as 
to structural design, quality and strength of materials. Floors shall be so 
constructed as to afford to walls, columns, piers, beams and other supporting 
members the lateral support which is required for their stability. 

*Sect. 1602. Type I: Fireproof Floor Construction. — (a) In 

buildings of Type I construction the floors shall be of steel, reinforced concrete, 
brick or structural clay tile arches, reinforced gypsum, or of combinations of 
these materials or other approved system of floor construction, and shall be 
of not less than three-hour fire-resistive construction as provided in Part 22. 
Floor beams which are spaced not further apart than half the spacing of 
columns, including in this case those connected to columns, may be considered 
as a part of the floor and not of the building frame for purposes of this section. 

(b) In buildings of Type I construction columns and framing supporting 
floors, where they are not supported on masonry walls or piers, and such mem- 
bers of the floor framing as are connected to columns or necessary for the 
stability of columns, except as otherwise provided in this section, shall be of 
structural steel protected by not less than four-hour fire-resistive protection 
or of reinforced concrete the reinforcement of which is so protected, except 
that fire protection need not be provided on steel or iron forms, on lintels not 
more than six feet in span in bearing masonry walls and not more than ten feet 
in span in non-bearing masonry walls, on supports for elevator guides and 
elevator machines except where they support other loads or brace the floor 
framing, on the metal framing of mezzanine floors which may be of wood as 
specified in this section, or on the landings of enclosed stairways. 

(c) Floors in Type I buildings may be covered with wood or other com" 
bustible flooring. Where wooden sleepers are used for laying wooden floors the 
space between the structural floor and the flooring shall be filled solidly with 
incombustible material under corridor and permanent partitions and else- 
where on continuous lines for at least a foot in width in such manner that there 
will be no hollow spaces under the flooring exceeding one thousand square feet 

(104) 



Sees. 1602-1603 

in area. Wooden flooring shall not underlie enclosure or toilet room parti- 
tions, nor masonry partitions. 

(d) Mezzanine floors in Type I buildings may be of wood or unprotected 
metal provided there are not more than two such mezzanines in any one room, 
the total area of the mezzanines does not exceed one third the area of the room 
or five hundred square feet, and one is not above the other. 

(e) The fire protective material required for structural steel shall prefer- 
ably be applied directly to the metal but structural steel members enclosed in 
spaces not over five thousand square feet in horizontal area, which are pro- 
tected above, below and on all sides by ceilings, floors and walls of four-hour 
fire-resistive construction and are unoccupied and inaccessible except in 
emergency, need not have other fire protection. 

(f) Ceilings in Type I buildings may be finished in wood or other combus- 
tible but not highly flammable material for ornamental, insulating, acoustical 
or similar purposes. Such material, with similar materials on walls and 
partitions, shall not exceed ten pounds per square foot of floor area enclosed 
by exterior walls and partitions of two-hour fire-resistive construction, nor a 
total of five thousand pounds if said floor space is enclosed in exterior walls 
and partitions of one-hour fire-resistive construction. Such materials shall 
be backed up by three-quarter inch plaster or equivalent fire-resistive material. 

[ *As amended by Ord. 1943, ch. 4 ] 

fSect. 1603, Type II: Semi=Fireproof Floor Construction. — (a) In 

buildings of Type II construction the floors shall be of incombustible materials 
and structural metal shall have one-hour fire-resistive protection. Floor 
beams which are spaced not further apart than half the spacing of columns, 
including in this case those connected to columns, may be considered as a 
part of the floor and not of the building frame for purposes of this section. 

(b) In buildings of Type II construction columns and framing supporting 
floors, where they are not supported on masonry walls or piers, and such 
members of the floor frame as are connected to columns or necessary for 
the stability of columns, except as otherwise provided in this section, shall 
be of structural steel protected by not less than two-hour fire-resistive pro- 
tection or of reinforced concrete the reinforcement of which is so protected, 
except that fire protection need not be provided on steel or iron forms, on 
lintels not more than six feet in span in masonry bearing walls and not more 
than ten feet in span in non-bearing masonry walls, on supports for elevator 
guides or elevator machines except where they support other loads or brace 
the floor framing, or on the landings of enclosed stairways. 

(c) Floors in Type II buildings may be covered with wood or other com- 
bustible flooring as provided in section sixteen hundred and two for Type I 
buildings. 

(d) The fire protective material required for structural steel shall prefer- 
ably be applied directly to the metal but structural steel members enclosed 
in spaces not over three thousand square feet in horizontal area, which are 
protected above, below and on all sides by ceilings, floors and walls of two- 
hour fire-resistive construction, and are unoccupied and inaccessible except 
in emergency, need not have other fire protection. 

(105) 



Sees. 1603-1604 

(e) Floor construction which consists of steel or other incombustible 
beams or joists, spaced not more than the thirty-six inches on centers, sup- 
porting a floor of reinforced concrete, steel plate or other incombustible 
materials, and protected on the under side by an incombustible ceiling of one- 
hour fire-resistive construction shall be considered as meeting the require- 
ments of this section. Enclosed spaces formed by such a ceiling shall not 
exceed five hundred square feet in horizontal area within incombustible fire 
stops of one-hour fire-resistive construction. 

(f) Ceilings in Type II buildings may be finished in wood or other com- 
bustible but not highly flammable material for ornamental, insulating, 
acoustical or similar purposes. Such material, with similar materials on walls 
and partitions, shall not exceed ten pounds per square foot of floor space 
enclosed with exterior walls, ceilings of three-hour fire-resistive incombustible 
construction, and partitions of two-hour fire-resistive construction, nor six 
pounds per square foot of floor space enclosed by exterior walls and par- 
titions of one-hour fire-resistive incombustible construction or a total of 
three thousand pounds. Such material shall be backed up by three quarters 
inch plaster or equivalent fire-resistive material. 

[ fAs amended by Orel. 1943, ch. 4 ] 

Sect. 1604. Type III: Heavy Timber Floor Construction. — (a) 

In buildings of Type III construction the floor planking, if of wood, shall 
be not less than one and five eighths inches thick, tongued and grooved or 
splined, and fire-stopped by a continuous layer of asbestos fabric or other 
approved fire-resistive material, covered with wooden flooring not less than 
three quarters inch thick, or equivalent protective flooring. Enclosed or 
concealed spaces shall be avoided. 

(b) Laminated floor construction consisting of lumber not less than one 
and one half inches nor more than three inches thick placed on edge, and 
securely spiked together, making a floor not less than three and one half 
inches thick, may be used in place of planking. 

(c) Floor beams in buildings of Type III construction, except as otherwise 
provided in this section, shall be of structural timber not less than five 
inches in least dimension nor less than forty square inches in cross-sectional 
area, but this limitation shall not apply to nailing strips supported on masonry, 
structural steel or the like. 

(d) Columns supporting floors in buildings of Type III construction shall 
be of structural timber not less than seven inches in least dimensions or of 
steel protected as specified in this section. Column caps for the support of 
beams and girders shall be of cast iron, steel or reinforced concrete, except 
that wooden bolsters may be used on columns supporting not more than a 
roof and one floor. Columns shall not rest upon the ends of wooden beams. 
Wood shall not be used for columns in basements or cellars. 

(e) The metal of steel column caps or of stirrups supporting beams or 
girders shall not be thinner than three sixteenths inch nor shall that of cast 
iron caps be thinner than one half inch. 

(f) Timbers supported on masonry walls shall be bevelled so that they 
may fall free of the wall in case of fire. 

(106) 



Sees. 1604=1607 

(g) Structural steel I-beams or columns of H section may be used instead 
of timber provided they are fireproofed by filling the space between flanges 
solidly with concrete or masonry held in place by ties through or secured to 
the web, or by enclosing the exposed faces in one-hour fire-resistive protection. 
Other structural steel shapes may be used for beams or columns, protected 
by one-hour fire-resistive protection. Standard weight steel pipe filled with 
concrete may be used for columns in buildings of Type III construction. 

(h) Floors shall be anchored to exterior and bearing walls and the beams 
thereof shall be connected to form continuous ties from wall to wall sufficient 
to resist the wind pressure specified in Part 23 applied outwardly to the walls. 

(i) Structural masonry and reinforced concrete shall not be supported 
upon wooden floor constructions, but this restriction shall not apply to fire- 
stopping, the protective foundations under heat-producing apparatus or to 
tile or concrete flooring with its base not more than four inches in total thick- 
ness, laid upon the planking. 

*Sect. 1605. Type IV: Light Wooden Floor Construction. — (a) In 

buildings of Type IV construction the floors may be of wood unprotected 
against fire. Floor beams and joists of wood shall not be less than one and 
five eighths inches thick. Where joists frame on a girder or bearing partition 
on both sides thereof, the spaces between the joists shall be fire-stopped 
with incombustible materials or with wood not less than one and one half 
inches thick. 

(b) Floors may be supported upon the masonry walls of the building or 
upon wooden columns or bearing partitions. Structural steel beams, steel or 
iron columns without protection against fire, reinforced concrete or other 
approved materials may be used in the floor framing or for its support. Wood 
shall not be used for columns or bearing partitions in basements or cellars. 

(c) Timbers supported on masonry walls shall be bevelled so that they 
may fall free of the wall in case of fire. 

(d) Floors shall be anchored to exterior and bearing walls and the beams 
thereof shall be connected to form continuous ties from wall to wall sufficient 
to resist the wind pressure specified in Part 23 applied outwardly to the walls. 

(e) Structural masonry and reinforced concrete shall not be supported 
upon wooden floor construction, but this restriction shall not apply to fire- 
stopping, the protective foundations under heat-producing apparatus or to 
tile or concrete flooring with its base not more than four inches in total thick- 
ness, laid upon the boarding. 

[ *As amended by Ord. 1943, ch. 4 ] 

Sect. 1606. Type V: Metal Frame Floor Construction. — In buildings 
of Type V construction the floors shall be constructed of incombustible 
materials. Structural steel or iron floor plates, structural steel beams, or 
steel or iron columns supporting floors need not be protected against fire. 

Sect. 1607. Type VI: Wooden Frame Floor Construction. — (a) In 

buildings of Type VI construction the floors may be of wood unprotected 
against fire. Floor beams and joists of wood shall be not less than one and 

(107) 



Sees. 1607-1608 

five eighths inches thick. Where joists frame on a girder or bearing partition 
on both sides thereof, the spaces between the joists shall be fire-stopped with 
incombustible materials or with wood not less than one and one half inches 
thick. 

(b) Floors may be supported upon the walls of the building or upon 
wooden columns or bearing partitions. Structural steel beams or steel or 
iron columns without protection against fire, reinforced concrete or other 
approved materials may be used in the floor framing or for its support. Wood 
shall not be used for columns or bearing partitions in a basement or cellar. 

(c) Structural masonry and reinforced concrete shall not be supported 
upon wooden floor construction, but this restriction shall not apply to fire- 
stopping, the protective foundations under heat-producing apparatus or to 
tile or concrete flooring with its base not more than four inches in total thick_ 
ness, laid upon the under boarding. 

Sect. 1608. Ratproofing. — (a) Every basement or cellar in buildings 
hereafter erected shall be completely covered with a ratproof floor of con- 
crete, or solid masonry laid in cement mortar, not less than two inches thick, 
or other approved flooring. Pits or openings in such floors shall be lined on 
all sides and the bottom with similar material. 

(b) Recesses and inaccessible spaces where rats might find refuge and 
breed shall be avoided if possible, and otherwise shall be sealed with masonry 
or with substantial wire mesh of incorrodible metal. 



(108) 



Sec, 1701 



PART 17. 
ROOF CONSTRUCTION AND COVERING. 

Section 

1701 — Roof Construction. 

1702 — Roof Covering. 

1703 — Roof Drainage. 

*Section 1701. Roof Construction. — (a) Except as otherwise pro- 
vided in this part, in so far as they are pertinent, the provisions of Part 16 
for the construction of floors and their supports shall also apply to the con- 
struction of roofs of buildings of the respective types of construction. 

(b) Members of structural steel frames of roofs and other incombustible 
roof construction covered with fire-retardant roofing, on Type I and Type II 
buildings, over rooms of Group B occupancy and over approved rooms of 
Group G occupancy shall be deemed to be sufficiently protected against fire 
if they are not less than twenty-five feet distant from the floor, and from a 
mezzanine floor or balcony below; or if they are not less than eighteen feet so 
distant and are protected by an incombustible ceiling of one-hour fire-re- 
sistive construction suspended at least one inch below the steel. Proximity 
within these limiting distances of an inclined or stepped balcony with fixed 
seats, of a mezzanine floor or level balcony not more than five feet wide, 
shall not be grounds for requiring greater fire protection than is required 
in this paragraph. The ceilings of such rooms and the walls more than five 
feet above the floor shall not be covered or finished with combustible material. 

(c) Filling for drainage on the roof of a building of Type I, Type II and 
Type V construction shall be of incombustible material except that wood, in 
amount not more than two board feet per square foot, may be used on a roof 
of Type I or Type II construction designed for a future floor. Filling for 
thermal insulation may be of combustible but not highly flammable material 
laid without air space. 

(d) In buildings of Type III the roof planking, if of wood, shall be not 
less than one and one half inches thick. Wooden columns supporting a roof 
in a building of Type III construction shall be not less than five inches in 
least dimension. 

(e) In buildings of Type III, Type IV and Type VI construction where 
the exterior wall is required by Parts 3 to 12, inclusive, to be of fire-resistive 
construction without unprotected openings, wooden joists, rafters and other 
combustible roof construction shall not extend through or across the exterior 
wall, except the roof boarding, planking or a nailing piece, which shall then 
be covered with metal. Such walls shall extend up to the under side of the 
roof boarding or planking and where required by Parts 3 to 12, inclusive, to 
be of four-hour fire-resistive construction without openings, shall have para- 
pets above the roof as specified in Part 14. Where such walls may have 

(109) 



Sees. 1701-1703 

unprotected openings combustible roof construction may project not more 
than one foot to form eaves except in the first and second fire zones. 
[ *As amended hij Ord. 1943, ch. 5 ] 

Sect. 1702. Roof Covering. — Roof covering on buildings of Type I, 
Type II or Type V shall be either fire-retardant or ordinary roofings as 
specified in Part 22. Roof covering on buildings of Type III, Type IV or 
Type VI shall be fire-retardant. 

Sect. 1703. Roof Drainage. — (a) Roofs of buildings and of all parts 
thereof shall be sloped to drain at a pitch of not less than one inch in ten feet. 
Gutters and conductors or leaders shall be provided at the low points to 
which water will flow, except on one story or two story buildings not over 
six hundred and fifty square feet in area, with drains to lead away and satis- 
factorily to dispose of rain water. Means shall be provided to prevent rain 
water from any part of a building except window sills, copings and cornices 
not more than one foot wide and awnings or marquises discharging off the 
outer edge, from filling or flowing upon a public way. 

(b) Where a roof is finished with a smooth surface of tile, terrazzo or 
similar material and under other favorable circumstances, the commissioner 
may waive the requirement of a slope and permit construction of a level roof 
subject to such conditions as he shall in any case specify. 

(c) No part of any roof shall be so constructed as to discharge snow or 
ice upon a public way. 

(d) Rain water leaders shall not be discharged upon a public way nor 
upon land of another owner, nor so as to flow upon such public way or land. 

(e) This section shall not be held to prevent the construction of a spray 
pond on a roof or the use of a roof to contain water for industrial or other 
approved purposes provided it is not allowed to become stagnant. 



(110) 



Sees. 180N1802 



PART 18. 
EXITS. 

Section 

1801 — General Requirements for Exits. 

1802 — Kinds of Exits. 

1803 — Number of Occupancies. 

1804 — Number and Location of Exits. 

1805 — Corridors and Passageways. 

1806 — Doorways as Exits. 

1807 — Windows as Exits. 

1808 — Interior Stairways. 

1809 — Interior Ramps. 

1810 — Smokeproof Towers. 

1811 — Exterior Stairways or Ramps. 

1812 — Fire Escapes. 

1813 — Ladders as Exits. 

1814 — Elevators as Exits. 

1815 — Horizontal Exits. 

1816 — Other Exits. 

1817 — Exit Enclosures. 

1818 — Exit Signs. 

1819 — Exit Maintenance and Lighting. 

Section 1801. General Requirements for Exits. — Every new building 
and every portion thereof shall have exits in conformity with this part and 
Parts 3 to 12, inclusive. No building shall be enlarged, altered or repaired 
in such manner as to reduce the number or capacity of exits to less than 
required nor shall the occupancy be changed unless the exits conform or are 
made to conform to the requirements for the new occupancy. 

Sect. 1802. Kinds of Exits. — (a) An exit from a room may be either — 



(b 



(c 



A doorway. 

A window. 

An exit from a story. 
An exit from a story may be either — - 

An interior stairway. 

An interior ramp. 

A smokeproof tower. 

An exterior stairway or ramp. 

A fire escape. 

A ladder. 

Elevators. 

An exit from the building or from the fire division. 
An exit from a building or from the fire division may be either — 

(HI) 



Sees. 1802=1804 

(1) A doorway in the exterior wall of the building opening upon a 
street or an open space with access to a street. 

(2) A horizontal exit. 

(d) All exits shall be of the kinds listed in the preceding paragraphs 
of this section subject to the limitations and requirements of this part, except 
that where two exits are required the commissioner may permit the substi- 
tution for one of them of sliding poles, chutes or other means of egress when 
all the persons who may in emergency need to use such means of egress are 
trained to their use in their daily occupations and when all other relevant 
conditions are satisfactory to the commissioner. 

(e) No exit of any kind may serve as a required exit unless it is or forms 
part of a continuous path of exit from the floor space served to the street. 

(f) At least one exit from every story of a building, except a basement, 
cellar, first or second story from which there is a doorway exit to a street or to 
an open space accessible to a street, shall be an interior stairway, an interior 
ramp or a smokeproof tower. 

*Sect. 1803. Number of Occupancies. — (a) The number of persons 
to be served by an exit shall be stated in the application for permit and shall 
be computed from the floor area on the following basis: 

(1) One person for every six square feet in auditoriums, assembly halls, 
dance halls, gymnasiums, armories, lodge rooms. 

(2) One person for every fifteen square feet in court rooms, restaurants, 
retail stores, class rooms in schools. 

(3) One person for every twenty-five square feet in lodging houses, 
reading rooms. 

(4) One person for every thirty-five square feet in factories and work 
rooms. 

(5) One person for every fifty square feet in offices and show rooms. 

(6) One person for every one hundred square feet in Group D buildings , 
hotels, apartments and other dwellings, police and fire stations. 

(7) One person for every two hundred square feet in automobile repair 
shops and service rooms, museums, libraries, wholesale stores, and club- 
houses, except in assembly halls thereof. 

(8) One person for every thousand square feet in storage garages and 
warehouses. 

(b) For other occupancies the commissioner shall determine the ratio of 
occupants to floor area in each case. 

(c) Where the kind or width of an exit depends upon the number of per- 
sons served by it, such number shall be determined by dividing the maximum 
number of persons in any room or group of rooms, or in any story and within 
a fire division, by the number of alternative exits to which they all have access 
less one (assuming that one such exit may be blocked) except where only one 
exit is required. 

[ *As amended, by Ord. 1943, ch. 5 ] 

fSect. 1804. Number and Location of Exits. — (a) Except as other- 
wise specified in Parts 3 to 12, inclusive, buildings and parts thereof shall have 
at least the number of exits required in this section. The kinds of exits pro- 

(112) 



Sec. 1804 

vided, as required in this part, shall be subject to the limitations imposed by- 
sections eighteen hundred and five to eighteen hundred and sixteen inclusive. 

(b) Every room and group of less than four rooms shall have at least one 
exit conforming to the requirements of this chapter. The exit from an attic or 
similar enclosed space, accessible but normally unoccupied, may be a scuttle 
not less than two feet by three feet in the ceiling of the story below. Such 
scuttle shall, if required by the commissioner, be provided with a permanent 
ladder. The flat roof of a building, if occupied by persons, shall be considered 
a room and a story for the purposes of this section. 

(c) Every room or group of rooms containing in the aggregate more than 
twenty-five hundred square feet of floor area or seventy-five occupants and 
every group of four or more rooms, except an attic or similar enclosed space, 
accessible but normally unoccupied, shall have at least two remote exits. 
Such exits may open into a common corridor which has at least two remote 
exits. Closets, vestibules, toilet rooms and the like shall not be counted as 
rooms of a group for the purpose of this paragraph. 

(d) When a story of a building is occupied by two or more tenants, each 
tenant shall have access to at least two remote exits from the story. 

(e) Every story in a building shall have at least two remote exits except : 

(1) Stories above the first story in single family dwellings less than three 
stories in height. 

(2) A basement or cellar constructed large enough for low pressure 
heating apparatus and its fuel storage only, requiring attendance of not 
more than two persons. 

(f ) Every room or story required to have two remote exits shall have two 
remote and independent paths of exit of the required width at all points. 

(g) A single exit from a room or group of rooms which has no other exit 
shall not be further than sixty feet from any point within the room or rooms 
measured along the path of exit. 

(h) Where two or more exits from a room are required they shall be 
remote or distant from one another in such manner that persons in any place 
may choose either of two directions in a path toward an exit, and in such a 
manner that a single fire in its early stages cannot block both paths toward an 
exit. The distance from any point in a room to the nearest exit, except as 
specifically indicated in special group requirements, shall not exceed one 
hundred and fifty feet in buildings of Type I, Type II and Type V nor seventy- 
five feet in buildings of Type III, Type IV and Type VI. 

(i) The exits from a story in a fire division shall be of such number and 
so located that at least one such exit is within one hundred and fifty feet in 
buildings of Type I, Type II and Type V, and within seventy-five feet in 
buidings of Type III, Type IV and Type VI, from every exit from a room or 
group of rooms into a corridor or, in a story without a corridor, from every 
point within the story and fire division, except* as specifically indicated in 
special group requirements. The distance to an exit, if a doorway, shall be 
measured to the nearer jamb thereof; if an enclosed stairway or ramp, to 
the doorway in the enclosure; and if a stairway or ramp not enclosed, to the 
nearest point of the top riser or commencement of slope. 
[ 1[As amended by Ord. 1943, ch. 5 ] 
(113) 



Sees, 1805=1806 

*Sect. 1805. Corridors and Passageways. — (a) A passageway shall 
be provided and maintained in every story of a building from all parts of 
the floor to the required exits, of width not less than the required width of 
the exit to which each leads, nor less than twelve inches for every one hun- 
dred persons served. 

(b) Corridors may serve as exits from the doorways from rooms to exits 
from the story. The clear exit width of corridors shall be not less than the 
required width of any doorway from which it leads, nor of the exit to which 
it leads, nor less than thirty-six inches nor less than twelve inches for every 
one hundred persons served. 

(c) Neither radiators nor pipes, doors in an open position nor any other 
equipment or construction shall be allowed to reduce or encroach upon the 
required width of a corridor. If lockers are placed along one or both sides 
of a corridor its clear width between lockers shall be increased over its required 
exit width by eighteen inches for each side on which lockers are placed and 
if other use than egress and lockers is made of corridors, the clear width 
shall similarly be increased over its required exit width as the commissioner 
shall in each case determine. 

(d) Passageways which serve as exits from enclosed stairways or ramps 
to exits from the building shall be enclosed corridors except where they may 
occur in a building which is not over forty feet wide and of a total area not 
exceeding two thousand square feet. In such a building one of the enclosed 
corridors in the first floor only may be omitted provided the basement and 
first story are equipped with automatic sprinklers and the class of construc- 
tion is Type IV or more fire-resistant. 

(e) The clear width of such passageways shall be not less than required 
for the stairway or ramp nor less than twelve inches for every one hundred 
persons in any story of the building served. The clear height shall be not less 
than seventy-eight inches. 

(f ) The floor and walls of a corridor serving as an exit from an enclosed 
stairway or ramp shall have fire-resistance of the rating required for the 
enclosure and the ceiling shall be of one-hour fire-resistive construction. 

(g) The floor of such a corridor shall be level or shall slope not over one 
vertical in ten horizontal, but such floor shall be level for a distance of forty- 
four inches from a stairway and at all doorways or connecting corridors for 
the full width thereof and one foot additional on each side. 

(h) An outside passageway leading from an exit from a building to a 
street shall have the clear width required for an interior passageway, and if 
covered shall be covered by incombustible construction. Such passageway 
shall be subject to all pertinent requirements for exits. 
[ *As amended by Ord. 1943, ch. 5 ] 

fSect. 1806. Doorways as Exits. — (a) Doorways which serve as 
required exits shall be not less than twenty-four inches wide. Doorways 
which serve as exits for more than ten persons shall be not less than seventy- 
eight inches high nor less than thirty inches wide nor less than twelve inches 
in width for every hundred persons so served. 

(b) The floor both sides of a doorway exit shall be at the same level for 

(114) 



Sees. 1806=1808 

a distance of three feet in either direction from the doorway, except that in 
doorway exits from a building to the outside there may be a single step-down 
not over six inches to a level landing not less than three feet wide. 

(c) Thresholds in exit doorways shall not be over one inch high. 

(d) In enclosures of stairways or ramps which serve as required exits, 
doors shall swing in the direction of egress. 

(e) Except in buildings of Group I, swinging doors in doorways which 
serve as required exits from the building shall swing in the direction of egress. 

(f) Revolving doors shall be of an approved type, without cable or bar 
braces, designed and constructed to release when simultaneous outward 
forces are exerted by persons of ordinary strength on both sides of the pivot 
so that the wings will fold back on themselves like the leaves of a book in 
the direction of egress. The use of revolving doors shall be limited as follows: 

(1) They shall not be used in occupancies of Group A, Group B, Group 
C, and Group D. 

(2) They may be used in other group occupancies only if swinging doors 
immediately adjacent to them provide seventj^-five per cent of the required 
egress. 

(3) They shall not be used in any exit from premises where alcoholic 
beverages are sold for consumption on the premises. 

(g) Except in detention buildings, doors in required exits shall not be so 
locked or fastened that they cannot be opened from the inside without use 
of a key. 

[ -\As amended by Ord. 1943, eh. 5 } 

Sect. 1807. Windows as Exits. — A window shall not serve as an exit 
except in an existing building and in such case only as the second of two re- 
quired exits serving not more than ten persons and subject to the approval of 
the commissioner and to such conditions as he may in each case prescribe. 
This provision shall not be held to limit the use of glass in a door. 

JSect. 1808. Interior Stairway. — (a) Interior stairways may serve as 
exits from any story of a building. Except as otherwise provided in this 
section, every interior stairway required to be enclosed shall have a direct 
doorway exit from the building or shall have an enclosed corridor leading to 
such exit, except as provided in paragraph (d) of Section 1805. 

(b) In buildings more than three stories high with flat roofs at least one 
interior stairway or ramp shall extend to the roof; and where more than two 
stairways or ramps serve as required exits, at least two shall be interior stair- 
ways or ramps which shall extend to the roof. In such buildings more than 
three hundred feet long there shall be at least two remote stairways or ramps 
extending to the roof. In a two-story or three-story building with flat roof, 
unless a stairway extends to the roof, there shall be a scuttle in the roof, not 
less than two feet by three feet, with a ladder, near a stairway. 

(c) An interior stairway shall be located entirely within the exterior walls 
of a building, but this requirement shall not be held to constrain the shape 
or plan of the exterior walls or the construction of the enclosure wall. 

(d) No interior stairway serving as a required exit shall be less than 
thirty inches wide except a single flight stairway to a balcony serving not more 

(115) 



Sec. 1808 

than ten persons which may be not less than twenty-four inches wide. No 
stairway serving as a required exit for ten or more persons shall be less than 
thirty-six inches wide nor less than twelve inches additional for every one 
hundred persons so served in excess of three hundred. The clear vertical 
headroom over each riser shall be not less than six feet six inches. 

(e) Interior stairways shall be enclosed where so required in Parts 3 to 12, 
inclusive, and in Part 15 of this code. 

(f) In buildings of Type I, Type II or Type V interior stairs, including 
landings, which serve required exits shall be constructed of incombustible 
materials, except that stairs with solid treads, risers and landings of incom- 
bustible materials may have top surfaces of wood, linoleum or other similarly 
combustible material. Treads, risers or landings of marble, slate or similarly 
brittle material shall be backed with sheet steel, for stairs three feet or less in 
width of at least number twelve gage, and for wider stairs at least number ten 
gage. Cast iron shall have a thickness of at least three sixteenths inch in 
treads and risers and three eighths inch in landings. Cast iron landings shall 
not have greater area than nine square feet between steel or other supports. 
Enclosed metal stairs and landings need not be protected against fire. Stairs 
which are not enclosed as provided in Part 15, in buildings of Type I or Type 
II shall have protection against fire as specified for floors. 

(g) In buildings of Type III, Type IV or Type VI not over three stories 
high, stairs, including landings, may be of wood. In buildings of Type III 
wooden stairs which are not enclosed as provided in Part 15 shall have treads 
at least one and one half inches thick; the risers, if any, shall be one and one 
half inches thick; stringers shall be not less than three and one half inches in 
least dimension; and the stairs shall be constructed without concealed spaces. 
Wooden stairs with soffits enclosed by plaster, sheathing or otherwise, shall be 
fire-stopped at floors and landings and not further apart than at every eighth 
riser with incombustible material or with wood not less than one and one half 
inches thick. 

(h) Treads and risers of stairs serving as required exits, except in schools, 
shall be so proportioned that the product of the tread and the rise in inches 
shall be not less than seventy nor more than seventy-seven; and the treads 
shall not be less than nine and one half inches nor the rise more than seven and 
three quarters inches. In schools, the treads and risers may be proportioned, 
with the approval of the commissioner, to suit the age of the pupils. Treads 
and risers shall be uniform throughout any one flight. 

(i) No flight of stairs shall have more than fifteen nor less than two risers 
between landings. A landing between two flights of stairs in the same 
direction shall be at least as wide as the stairs and at least three feet long in 
the direction of travel. Stairs turning at a right angle shall have a square 
or rectangular landing the full width of the respective stairways. Where 
stairs return directly on themselves, a landing without steps shall be provided 
at least as wide as the stairs. 

(j) Spiral stairs shall not be used in a stairway serving as a required exit 
for ten persons or more nor in stairways more than one story in height, except 
in a single family dwelling; and in pre-code buildings with the approval of 

(116) 



Sees. 1808-1809 

the commissioner. Stairs may be curved if the tread and rise one foot from 
the inner rail are as specified in this section. 

(k) Where stairs and landings are not guarded at the side by a wall or 
partition, they shall have a railing, balustrade, grille or similar guard at least 
thirty-three inches high at the face of the riser. In case a stairway more than 
two stories high has recurring flights and landings, about an interior well 
more than twelve inches wide in horizontal projection, the guard next the 
well shall be not less than three feet high at the face of the riser, and shall con- 
sist, if a railing, of at least two rails, if a balustrade, of balusters not over 
six inches apart, and if a grille or other form of guard, of meshes not more 
than six inches in least dimension, and the edge of the stairs and of the land- 
ings shall have a curb at least three inches high. 

(1) Stairs less than forty-four inches wide shall have a handrail on one 
side; stairs forty-four inches wide or more and curved stairs shall have hand- 
rails on both sides. Where the width of a stairway is required, as an exit, 
to exceed eighty-eight inches one or more intermediate handrails shall be 
provided not over eighty-eight inches apart. Handrails shall be about three 
feet high above the center of the treads, shall be continuous between landings 
and in stairways which serve as required exits, handrails which are not con- 
tinuous shall be returned at the upper end to the wall or terminate at a post 
in such manner as not to leave a free or projecting end. Handrails may be 
of wood. 

(m) No pipe, radiator or other equipment shall obstruct or encroach upon 
the required width of a stairway or landing. No stairway which serves as a 
required exit shall be obstructed while the building is occupied, within the 
enclosure thereof, on the steps or landings or on the floors within the area 
required for exit or for approach to the stairway, by materials, equipment 
or by any use of such space except for passage. 

(n) There shall be no closet within the required enclosure of a stairway. 
There shall be no closet for storage under a stairway of combustible material 
which is a required exit except a coat closet in dwellings or a toilet or similarly 
non-hazardous use, and in such case the soffit of the stairway shall be pro- 
tected by a ceiling of one-hour fire-resistive construction. 
[ %As amended by Ord. 1943. ch. 5 ] 

*Sect. 1809. Interior Ramps. — (a) Interior ramps may serve as 
exits from any story of a building. 

(b) An interior ramp shall be located entirely within the exterior walls of 
a building. 

(c) The width, enclosure, guarding and construction of ramps shall be 
the same as provided for interior stairways. All requirements for interior 
stairways which are pertinent shall also apply to interior ramps except the 
requirement for handrails. 

(d) Ramps which serve as required exits shall not have a slope greater 
than one vertical in ten horizontal. 

[ *As amended by Ord. 1943, ch. 5 J 

(117) 



Sees. 1810=1811 

*Sect. 1810. Smokeproof Towers. — Smokeproof towers, if built, may 
serve as required exits from any story of a building. Interior stairways con- 
structed and arranged as follows shall be known as smokeproof or fire towers. 

(a) The enclosed walls of fire towers shall be of incombustible materials 
or assemblies having a fire-resistive rating of at least four hours. Such walls 
shall be without openings, except for doors serving as means of egress. 

(b) At each story served by a fire tower access to the stairways of such 
fire tower shall be provided through outside balconies or fire-proof vestibules. 
Such balconies or vestibules shall be at least three feet eight inches in width 
and shall have unpierced floors of incombustible materials and shall be pro- 
vided with substantial guard rails at least four feet high, without any open- 
ings greater than eight inches in width." 

(c) Such balconies or vestibules of fire towers shall be level with the floors 
of the structure and the platforms of the stairs connected by such balconies. 
Such balconies or vestibules shall be separated from the structure and the 
stairs by self-closing fire doors capable of being opened from both sides 
without the use of a key, except the final balcony or vestibule as described 
in paragraph (d) which may open only from one side without the use of a key. 

(d) Balconies or vestibules of fire towers shall open on a street or yard 
or on a court open vertically to the sky for its full height, having a minimum 
net area of one hundred and five square feet and a minimum dimension of 
seven feet. The opening from the vestibule to the street, yard or court shall 
have a minimum area of eighteen square feet and a minimum dimension of 
two feet six inches. It shall be unlawful to leave openings in the court walls 
surrounding an interior fire tower other than the openings from the vestibules, 
within fifteen feet of the balcony, except that self-closing fire windows may be 
used if such windows are at least ten feet from the balcony, provided that the 
area of the court is at least twelve feet by twenty-four feet. 

(e) Fire towers shall terminate at the grade level and shall exit directly 
to the street independently of corridors serving other stairways except when 
the fire tower terminates in the ground floor corridor outside of the inner 
vestibule and within ten feet of the building line. 

(f) Doors opening into fire towers may be constructed with observation 
panels made of polished wire glass, one-quarter of an inch thick, if such glass 
is set with a three-quarter inch rabbet. Such glass shall have a maximum 
area of sixteen square inches. Doors shall be capable of being opened from 
both sides without the use of a key. A handrail shall be provided on both 
sides. 

[ *As amended by Ord. 1943, ch. 5 ] 

Sect. 1811. Exterior Stairways or Ramps. — (a) Exterior stairways 
or ramps may serve as required exits from any story or stories of a building. 
Except as to enclosure and location within the exterior walls of a building, 
an exterior stairway or ramp shall conform to the requirements for interior 
stairways or ramps, respectively. Exterior stairways or ramps shall be 
located outside the exterior walls of a building, but not nearer than five 
feet from a lot line other than a street line. 

(b) Exterior stairways or ramps serving as required exits, and their land- 

(118) 



Sees. 1811=1812 

ings, railings and enclosures, if any, shall be of incombustible materials except 
on buildings of Type VI construction and except that handrails may be of wood. 

(c) A doorway serving as an exit from a story to an exterior stairway or 
ramp shall open upon a landing level with or not more than one six-inch step 
below the floor, and shall be protected except in buildings of Type VI con- 
struction by a self-closing Class B fire door. Openings for doorways or win- 
dows under or within five feet from an exterior stairway or ramp, except in 
buildings of Type VI construction, shall be protected by automatic-closing 
Class B fire doors or fire windows, unless the exterior stairway or ramp is 
enclosed in one-hour fire-resistive construction. 

(d) Except where guarded on the side by the exterior wall of the building, 
or by an enclosing wall, an exterior stairway or ramp more than three stories 
or thirty feet above the ground shall be guarded by a railing, balustrade or 
grille not less than six feet high with openings not more than six inches wide. 

*Sect. 1812. Fire Escapes. — (a) Fire escapes shall not be erected to 
serve as required exits except as follows : — 

(1) From pre-code buildings where ordered by the commissioner under 
the provisions of Section 16 of Part I. 

(2) From post-code buildings four stories or less in height and five 
thousand square feet or less in area. 

(3) Where ladders may serve as exits. 

(4) As emergency exits from buildings of Group A or Group B occu- 
pancy as provided in Parts 3 and 4, and 

(5) Where ordered by the commissioner under the provisions of section 
sixteen of Part 1. 

(b) Fire escape landings and stairs shall have a clear exit width of not 
less than twenty-four inches where the maximum number of persons to be 
served does not exceed one hundred and forty-four, and an additional one 
inch in width shall be added for each additional six persons served, excepting 
therefrom emergency exits as required in Group A and Group B. 

(c) Fire escapes shall be of incombustible materials. 

(d) The floors of fire escape balconies or landings, if of steel, shall be of 
open construction with steel bars not over one half inch nor less than one 
quarter inch wide and spaces not over one and one quarter inches each nor 
less in the aggregate than two thirds the floor area. The bars shall be rigidly 
spaced near their ends and at intervals not exceeding two feet. Floors shall 
be securely attached to supports. 

(e) Fire escape stairs, if steeper than is allowed for interior stairs, shall 
not be steeper than necessary, nor in any event steeper than sixty degrees 
with the horizontal. Stairs steeper than sixty degrees shall be deemed 
ladders and shall not be used for exits except where ladders are allowed. 
The product of the tread and rise in inches shall be not greater than seventy- 
seven and the rise shall not exceed nine inches. The construction of the 
tread shall be as required for landing floors, if of steel, and not less than seven 
and one-half inches wide. Treads shall be securely attached to stringers. 
There shall not be less than three nor more than fifteen risers between 
landings. 

(119) 



Sees. 1812-1813 

(f ) The sides and ends of fire escape landings and the sides of stairs, where 
not guarded by a wall, shall have a railing at least three feet high, consisting 
of a bar not less than one and one half by three eighths inch and a balustrade 
of half-inch round bars or equivalent with a lower rail. The railing shall be 
supported by posts and shall be sufficient to withstand safely a lateral force 
of twenty pounds per foot of rail, and in Group H and Group I shall have 
one-half inch round bar palings not over six inches from center to center. 

(g) Openings for doorways or windows under or within five feet from a 
fire escape, except in buildings of Type VI construction, shall be protected 
by automatic-closing Class B fire doors or fire windows, unless in the case of 
show windows or other windows the commissioner modifies this requirement 
in consideration of other specific provisions contributing to safe egress over 
the fire escape in question. 

(h) Fire escapes shall not be bracketed from masonry walls more than five 
times the thickness of the wall. Bracketed cantilevers shall be bolted through 
the wall with plate washers set in mortar on the inside. 

(i) Except in the webs of structural channels and I-beams, and in the 
recticular or cross bars of factory-assembled floor gratings approved as 
flooring for fire escapes, the steel in fire escapes shall not be thinner than 
one quarter inch nor shall bolts be less than three eighths inch. Stove bolts 
shall not be used. If stringers of stairs are spliced, the splice shall be made 
by riveting or welding, and not by bolting. 

(j) The lowest run of fire escape stairs may be hinged near the top to 
swing up into a horizontal position when not in use. Such runs shall be 
counter-balanced but not so heavily that they will fail to lower by gravity 
when released. The hinge shall consist of a single round bar, not less than 
seven eighths inch diameter, with approved bearings on both stringers of the 
lower run and properly supported. The hinge bar shall be not less than two 
inches horizontally back from the nosing of the stair tread under which it is 
placed. The hinged run shall be held in horizontal position by a bent bar 
at least seven eighths inch in diameter, rigidly held in bearings and bent 
across the stairway above the hinged run in such manner that a person using 
the fire escape for egress must release the hinged run before reaching it, or 
by other approved device. 

[ *As amended by Ord. 191+3, ch. 5 ] 

fSect. 1813. Ladders as Exits. — (a) Ladders shall not serve as 
exits except where specifically allowed in this part and in Parts 3 to 12, in- 
clusive. A ladder not more than one story high may serve as exit where a 
scuttle is allowed. 

(b) Ladders serving as exits shall be permanently fixed in place and shall 
be not over fifteen feet in length. In buildings of Type I, Type II and Type V, 
ladder exits shall be incombustible. Rungs shall be uniformly spaced, not 
over twelve inches top to top, and shall be supported by two rails not less 
than twelve inches apart. 

[ \As amended by Ord. 1943, ch. 5 } 
(120) 



Sees. 1814=1815 

*Sect. 1814. Elevators as Exits. — (a) Elevators may serve as 
exits from stories of buildings where all the following requirements are com- 
plied with, namely : — 

(1) There are at least two other remote exits from the stories conform- 
ing with the provisions of Section 1804 and not less than three feet six 
inches wide. 

(2) The elevators shall be passenger elevators, not less than two in 
number enclosed in a single shaft or in adjoining shafts. The elevators 
shall have capacity to evacuate the occupants of any floor in five trips each. 

(3) The elevators shall be in operation and in charge of licensed opera- 
tors during usual business hours and when the building is occupied. 

(4) The elevators shall have a lobby outside their enclosure in each 
story served by the elevators with a floor area of at least two square feet 
for every occupant in the story, separated from the occupied area of the 
story by partitions of not less than one-hour fire-resistive construction. 
Vertical openings within such lobbies shall be enclosed in all stories in 
which they occur. Corridor space contiguous to the lobby shall be con- 
sidered a part of the lobby. 

(5) In buildings of Type III or Type IV construction, the enclosure 
of lobbies in successive stories shall be continuous, forming a complete 
one-hour separation as specified in Part 13, through all stories. 

(b) Elevators serving as exits shall have sufficient speed to make a round 
trip from first story to top and back without intermediate stops in two minutes. 
[ *As amended by Ord. 1943, ch. 5 ] 

Sect. 1815. Horizontal Exits. — (a) A horizontal exit shall consist 
of a doorway in an exterior or party wall of a building or in a fire wall separat- 
ing two fire divisions of a building, which leads to a story, in another building 
or fire division, at the same or approximately the same level, from which 
egress may be made. 

(b) A horizontal exit may serve as an exit from a room, from a story or 
from a building, but not from the interior stairway or ramp required in 
paragraph (f) of section eighteen hundred and two. 

(c) The clear floor area in the story in the building or fire division to which 
a horizontal exit leads shall be sufficient to contain the occupants of the story 
in both buildings or fire-divisions allowing three square feet for each person. 

(d) A horizontal exit shall have at least the width required for it as an 
exit, or for the exits which it serves as outlet. 

(e) Where the floors connected by a horizontal exit are at different levels 
a ramp shall be provided the full width of the exit sloping not over one vertical 
in ten horizontal, with guard railing on the open sides. 

(f ) The doorway of a horizontal exit in an exterior wall of a building may 
lead to an adjoining or nearby building by means of a connecting balcony 
or bridge or by a tunnel, at least as wide as the doorway. The floor of such 
balcony or bridge, except as provided in paragraph (g) of this section, shall be 
solid of Type I construction, and shall be level with, or not more than one 
six-inch step down from, the floors with which it connects. The floor of such 
a balcony, bridge or tunnel shall be horizontal or have a slope not exceeding 

(121) 



Sees. 1815=1819 

one vertical in ten horizontal, and shall not contain steps or stairs except with 
the approval of the commissioner. Unless the balcony or bridge is enclosed 
in one-hour fire-resistive incombustible construction, doorways or windows 
opening on or under, or within five feet from such balcony or bridge, shall 
have automatic-closing Class B fire doors or fire windows. The open sides 
of such balcony or bridge shall be guarded as required for the landings of 
exterior stairways. 

(g) Connecting balconies of fire escape construction may be used for 
horizontal exits only where fire escapes are permitted. 

Sect. 1816. Other Exits. — Sliding poles, chutes or other devices pro- 
vided as means of egress shall conform in all respects to such requirements 
as the commissioner shall in any case prescribe. 

Sect. 1817. Exit Enclosures. — (a) Interior stairways and ramps shall 
be enclosed as specified in Parts 3 to 12, inclusive, and in Part 15. 

(b) Interior stairways and ramps which serve as required exits from 
stories above the second story shall be enclosed, except as otherwise provided 
in Parts 3 to 12, inclusive, in all stories in which they occur. 

(c) Doors in a stair enclosure shall be automatic or self-closing and shall 
never be locked against egress except in detention buildings. Such doors 
shall swing in the direction of egress and shall not in any position reduce the 
width of the stairway or its landings below that which is required. 

Sect. 1818. Exit Signs. — Required exits, except in buildings of Group I, 
Division 1, shall be marked by suitable signs sufficiently illuminated to be 
easily read when the building is occupied. If exits are located where they 
would not be expected to be found, directing signs shall be provided as they 
may be required by the commissioner. 

Sect. 1819. Exit Maintenance and Lighting. — (a) Required stair- 
ways, passageways, corridors and other exits shall be at all times maintained 
in safe condition, and when the building is occupied, shall be kept clear of 
obstructions and ready for use. 

(b) Outside stairs and fire escapes and the vestibules of smokeproof 
towers shall be cleared promptly of ice or snow. Awnings shall not be per- 
mitted to interfere with fire escapes. 

(c) Required stairways, passageways, corridors and other exits, interior 
or exterior, except in single-family dwellings and within apartments or suites 
of buildings of Group H and Group I, shall be kept adequately lighted when 
the building is occupied, or shall be provided with approved means for light- 
ing which can be turned on by an occupant at a convenient point or points. 



(122) 



Sec. 1 90 1 



PART 19. 
DOORS, WINDOWS AND SKYLIGHTS. 

Section 

1901 — Doors. 

1902 — Windows. 

1903 — Skylights. 

1904 — Sidewalk Lights. 

^Section 1901. Doors. — -(a) Doors in doorways which serve as re- 
quired exits shall conform to the requirements of Part 18. 

(b) Doorways in enclosures of vertical openings shall have doors which 
conform to the requirements of Part 15. 

(c) Doorways in required separations between two units of occupancy or 
between two fire divisions of a building shall have doors which conform to the 
requirements of Part 13. 

(1) Except where otherwise specified in this code, doorways in walls 
required to have one-hour resistance to the spread of fire shall have doors 
which, if of wood, shall be not less than one and one half inches thick in 
any part. Such doors, if not of wood, or if larger than twenty-five square 
feet in area, shall be Class C fire doors. 

(2) Except where otherwise specified in this code, doorways in walls 
required to have two-hour resistance to the spread of fire shall be automatic- 
closing Class B fire doors. 

(3) Except where otherwise specified in this code, doorways and other 
openings in walls required to have three-hour resistance to the spread of fire 
shall have automatic-closing Class B fire doors on both sides of the wall. 
The sum of the areas of such openings in one story shall not exceed one-half 
the area of the sum of said walls and no single opening shall be greater in 
area than two hundred square feet. 

(4) Doorways and other openings in party walls and, except where 
otherwise specified in this code, in walls required to have four-hour re- 
sistance to the spread of fire, shall have automatic-closing Class A fire 
doors on both sides of the wall. The sum of the areas of such openings 
in one story shall not exceed one-half of the sum of the areas of said party 
walls and no single opening shall be greater in area than one hundred 
square feet. 

(5) In the protection of openings less than two square feet in area in 
fire-resistive walls, the commissioner may waive in part or modify the 
requirements of this section subject to such conditions as he shall in each 
case specify. 

(6) In doorways required to have specified width and height a stop 
moulding forming a rabbet of the frame may project on each side and at 
the top not more than three-quarters of an inch inside the required dimen- 

(123) 



Sees. 1901=1903 

sions. The door, in open position, shall clear the required width of the 
doorway completely and the door and frame shall have additional width 
if necessary for this purpose. 

(7) Doors required to be automatic-closing shall be self-closing and 
normally closed, or equipped to close automatically by the action of heat 
in the event of fire. 

[ *As amended by Ord. 1943, ch. 5 ] 

fSect. 1902. Windows. — (a) Fire windows shall conform to the 
requirements of Part 22. 

(b) Windows in exterior walls of buildings shall conform to the require- 
ments of Parts 3 to 12, inclusive, and Parts 14 and 20. 

(c) Windows in enclosures of vertical openings shall conform to the 
requirements of Part 15. 

(d) Windows in required separations between two units of occupancy or 
between two fire divisions of a building shall conform to the requirements 
of Part 13. 

(e) Windows in other walls and partitions required to have resistance to 
the spread of fire shall be fire windows. 

(f) In walls and partitions the openings of which are required to have 
the protection of fire doors, a fixed fire window may be considered equivalent 
to one Class B fire door, but two such windows shall not be substituted as 
equivalent to two doors in an opening where two fire doors are required. 

(g) In the exterior walls of buildings of approved occupancy and con- 
struction the commissioner may allow the substitution of an approved system 
of open sprinklers and ordinary windows for the fire windows specified in 
this section. 

(h) Windows in exterior walls of elevator shafts shall be protected by 
vertical metal bars not less than five eighths inch in diameter, outside the 
sash, forming spaces not more than ten inches wide, firmly secured in the 
opening. 

(i) Openings in cellar and basement walls shall have effective protection 
against the passage of rats. 

(j) In display windows fronting on a public way, in the first story of a 
building, a bulkhead may be constructed which shall be of the same type 
of construction as the first floor. Where the first floor is continuous to the 
exterior wall without opening, a platform of wood or other combustible 
material may be built to form the raised floor of the display space. In dis- 
play windows, fronting on a public way, not more than two stories high, 
the back, sides and ceiling of the display space, shelves, partitions and the 
like, and entrance vestibules and doorways in connection with such display 
windows, may be of wood or other combustible but not highly flammable 
material; provided, that this paragraph shall not be construed to allow a 
vertical opening in any floor without the enclosure specified in Part 15. 
[ fAs amended by Ord. 1943, ch. 5 ] 

JSect. 1903. Skylights. — (a) Except on greenhouses skylights shall 
be of incombustible materials. 

(124) 



Sees. 1903-1904 

(b) Except on greenhouses, and except over photographic studios with 
the approval of the commissioner, skylights shall be glazed with wire glass 
or shall be protected by wire screens. Such screens shall be of at least No. 12 
gage wire with not larger than one-inch mesh, on substantial metal supports, 
at least six inches but not more than twelve inches above the glass and parallel 
thereto, and projecting at least six inches beyond the edge of the skylight. 

(c) Skylights over stairways and corridors, except in buildings of Group I, 
and skylights over restaurants, halls and other public rooms, shall be glazed 
with wire glass or protected by a wire screen or a ceiling light of wire glass 
below. 

(d) Skylights, except the glass thereof, shall be designed to support the 
loads provided in Part 23 for roofs of corresponding slope. 

(e) The parts of skylights exposed to the weather, gutters for leakage 
or condensation, outside screens and their supports if of metal, shall be of 
metal protected against corrosion. 

[ |As amended by Ord. 1943, ch. 5 ] 

Sect. 1904. Sidewalk Lights. — Glass units of approved shape, size 
and thickness may be set in reinforced concrete roofs, floors or sidewalks, 
with or without metal shields, in a manner approved by the commissioner. 
Screen protection shall not be required above or below such construction 
except where specifically required by the commissioner. 



(125) 



Sees. 2001=2002 



PART 20. 
PENTHOUSES AND ROOF STRUCTURES. 

Section 

2001 — Height of Buildings. 

2002 — Penthouses. 

2003 — Roof Structures. 

*Section 2001. Height of Buildings. — (a) Limitation, wherever it 
occurs in this code, upon the height of buildings measured to the highest 
point of the roof thereof shall not be held to limit the height of the steeples 
of churches, towers, domes, cupolas, belfries, parapets, or other walls, cor- 
nices, statuar}^, balustrades, railings, flag poles, weather-vanes, chimneys, 
vent pipes, skylights, ventilators, steam exhausts, tanks, signs and pent- 
houses for the enclosure of tanks, stairways, elevator machinery, ventilating 
fans and the like, erected upon or above the roof of a building, provided 
such structures shall not be occupied by persons nor be used for storage or 
for a manufacturing process requiring constant or frequent attendance. 

(b) The provisions of this part shall not be held to authorize construc- 
tion of any kind above the limit of height specified for every part of a build- 
ing in section one hundred and thirty-six of Part 1 of this code. 

(c) The limitation of height of buildings contained in Parts 3 to 12, in- 
clusive, of this code and the provisions of this part shall not be held to pro- 
hibit the use of the open roof of a building, nor the la\dng of suitable flooring 
over the roof covering, which conforms with the provisions of this code for 
the type of construction of the building. 

[ *As amended by Ord. 1943, ch. 5 ] 

Sect. 2002. Penthouses. — (a) Penthouses enclosing elevator machin- 
ery, ventilating fans, tanks, elevators, stairways and the like shall not be 
larger than reasonably necessary for their purpose, including the storage of 
tools, spare parts, appliances and materials necessary for the maintenance 
and repair of such equipment. 

(b) Penthouses on buildings of Type I or Type II construction shall be of 
incombustible materials and the walls and roofs thereof shall afford protection 
against fire outside of one-hour fire-resistive construction. Doors and win- 
dows in such walls shall be Class C fire doors or fire windows. 

(c) Penthouses on buildings of Type V construction shall be of incom- 
bustible materials including the doors and windows thereof. 

(d) Penthouses on buildings of Type III, Type IV or Type VI shall be 
of the same type of construction as the building and the walls thereof may 
be constructed as provided in this code for partitions, covered on the outside 
by metal, cement plaster on metal lath or equally fire-retardant covering. 

(e) The wall of a penthouse which rests upon the exterior wall of a build- 
ing shall conform to the requirements of this code for an exterior wall. 

(126) 



Sees. 2002=2003 

(f) Except where used as provided for in paragraph (a) of this section, a 
penthouse upon the roof of a building shall be considered an additional story 
or additional stories of the building and shall conform to the requirements 
therefor. The provisions of this section shall not be held to limit the con- 
struction of such additional stories. 

Sect. 2003. Roof Structures. — (a) The walls of dormers shall be 
constructed as specified in this code either for the exterior walls or for the 
roof of the building on which they are built. 

(b) Where persons occupy or use the open roof of a building, such roof 
or the portion so occupied shall be guarded by a parapet wall or approved 
fence or railing not less than forty- two inches high. 

(c) Except as otherwise provided in this part, and except flag poles and 
water tanks, all structures erected on the roof of a building shall be of incom- 
bustible materials. 



(127) 



Sees. 2101=2102 

PART 21. 
CHIMNEYS AND HEATING APPARATUS. 

Section 

2101 — Support of Chimneys. 

2102 — Chimney Construction. 

2103 — Chimney Height. 

2104 — Wood near a Chimney. 

2105 — Smokestacks. 

2106 — Smoke Pipes. 

2107 — Fireplaces. 

2108 — High Pressure Boilers. 

2109 — Low Pressure Boilers. 

2110 — Hot Air Furnaces. 

2111 — Hot Air Pipes and Registers. 

2112 — Electric Ranges, Water Heaters and Hot Plates. 

2113 — Domestic Stoves and Ranges, 

2114 — Commercial Stoves and Ranges. 

2115 — Oil Burners. 

2116 — Incinerators. 

2117 — Support of Heat Producing Apparatus. 

21 18 — Smoke Connection. 

2119 — Other Heat Producing Apparatus. 

*Section 2101. Support of Chimneys. — ■ (a) A chimney shall support 
no vertical load except its own weight, but this provision shall not apply to 
masonry bonded to a chimney outside the required thickness thereof, nor shall 
it be held to forbid a suspended staging for erection or maintenance. An 
independent or free-standing chimney shall be stable and shall support its 
weight and resist the force of the wind without exceeding the stresses allowed 
by this code for the materials of which it is constructed. 

(b) Unless corbelled from a masonry wall, a chimney shall be supported 
upon a foundation of masonry or reinforced concrete conforming to the pro" 
visions of Part 29, upon the furnace which it serves, if of masonry and capable 
of supporting the chimney, or upon primary framing of Type I or T}^pe II 
construction. 

(c) No chimney shall be corbelled from a masonry wall more than the 
thickness of the wall nor from a wall less than twelve inches thick. 

[ *As amended by Ord. 1943, ch. 5 ] 

Sect. 2102. Chimney Construction. — (a) The walls of chimneys 
shall be of brick, stone, cast stone, concrete blocks, structural clay tile or plain 
or reinforced concrete, with such lining as is specified in this section. 

(b) For the purposes of this part the lining of a chimney flue shall mean 
the material forming the inner surface of the flue, whether the remainder of 
the chimney wall is (1) integral with the lining, (2) additional thickness of 
similar material or (3) of different materials. Except as otherwise specified 
in paragraph (i) of this section, the lining of every flue in a chimney shall be 
of burned clay or shale brick not less than three and one' half inches thick of 

(128) 



Sec. 2102 

A or B quality as specified in Part 24, or of refractory material as specified 
in this section. The lining of every chimney flue more than two hundred 
and fifty-six square inches in area of cross-section shall be of refractory 
material from a point not less than twice the inside diameter of the chimney 
(the larger diameter if rectangular) below the bottom of the smoke pipe 
entrance, or from the bottom of the flue, to a point not less than six times such 
inside diameter above the top of the smoke pipe entrance. Refractory 
material shall consist of burned fire clay flue lining not less than five eighths 
inch thick, fire brick not less than three and one half inches thick, or radial 
hollow clay chimney tile, made of suitable refractory clay capable of with- 
standing the heat and corrosive effect of flue gases and having a softening point 
not lower than nineteen hundred degrees Fahrenheit. In such a chimney 
mounted upon a masonry furnace the required refractory flue lining shall be 
continuous with the lining of the furnace and shall extend not less than six 
times the inside diameter of the flue above the top of the furnace. 

(c) Burned fire claj'" flue linings shall be built in as the masonry of the 
chimney is laid. All joints and spaces between the masonry and lining shall 
be thoroughly filled with mortar as each course of the masonry is laid. 
Cracked, broken or otherwise defective flue lining shall not be used in a 
chimney. Fire brick or radial tile lining shall be laid in fire clay or with 
narrow beds and joints of mortar. Burned clay or shale brick lining shall be 
laid in mortar or fire clay. Brick or radial tile lining may be separated from 
the chimney wall provided the wall outside the lining is not less than eight 
inches thick, and both wall and lining are independently stable. 

(d) Not more than three flues of burned fire clay flue lining may be laid 
contiguous in a chimney nor shall the aggregate width of such contiguous 
flues exceed thirty-seven inches without separating masonry withes at least 
four inches thick bonded to the walls of the chimney. Walls of brick between 
two flues in a chimney shall be not less than three and one half inches thick. 

(e) The masonry wall of a chimney outside the flue lining shall be not less 
than four inches thick. In chimneys of radial hollow clay chimney tile in 
which wall and lining are integral the total wall thickness shall not be less than 
six inches. 

(f) Stone masonry of sawed or dressed stone in courses, well bonded at 
corners and tied with anchors of non-corrodible metal shall be not less than 
four inches thick outside the flue lining. Chimney walls of other stone 
masonry shall be not less than twelve inches thick outside the flue lining. 

(g) Concrete block masonry shall not be used in an independent or free- 
standing chimney nor in chimneys bonded to walls more than three stories 
in height. 

(h) Structural clay load-bearing tile of A grade, as specified in Part 24, 
may be used in the walls of chimneys, or radial hollow clay chimney tile of 
equivalent qualit}". Other hollow clay tile shall not be used. Units shall 
be so laid that the ends of cells are not exposed. 

(i) Chimneys of concrete cast in place shall be reinforced for shrinkage 
and temperature stresses. Concrete integral with the chimney wall shall be 
considered satisfactory flue lining in such chimneys above a point thirty feet 
above the smoke entrance, and in flues less than one hundred and forty-four 

(129) 



Sees. 2102-2105 

square inches in area in buildings of Group I, Division 1, provided the con- 
crete walls are not less than six inches thick and the concrete is proportioned 
for a strength of two thousand pounds per square inch as specified in Part 26. 

(j) Chimneys shall have a coping at the top for protection of the masonry 
from the weather. 

Sect. 2103. Chimney Height. — (a) Chimneys shall be carried to a 
height sufficient to protect adjoining buildings from fire and smoke and unless 
the roof is covered with incombustible material, shall extend at least thirty 
inches above the highest point of intersection with the roof. 

(b) Chimney flues shall have a well below the entrance of the lowest 
smoke pipe and shall be provided with a metal cleanout door with built-in 
frame. 

*Sect. 2104. Wood near a Chimney. — (a) No chimney shall 
be built nearer than one inch from wooden floor or roof joists or nearer than 
one inch from wooden studding, furring or other woodwork. The space 
about a chimney shall be fire-stopped at each floor and ceiling level with 
incombustible material, unless such space is treated as a vertical opening 
and is enclosed as provided in Part 15. 

(b) In case wooden beams or other woodwork are supported on a masonry 

wall or pier bonded to a chimney, such woodwork shall not be nearer than 

four inches from the chimney. For the purposes of this section a chimney 

shall consist of the flue or flues, the lining, if any, and the walls to the 

required thickness. 

[ *As amended by Ord. 1943, ch. 5 ] 

fSect. 2105. Smokestacks. — (a) A smokestack shall support no 
vertical load other than its own weight, but this shall not be held to forbid 
a suspended staging for erection or maintenance. A smokestack exposed to 
the force of the wind shall be capable of resisting such force and support its 
own weight without exceeding the stresses allowed by this code for the 
materials of which it is constructed. 

(b) A smokestack shall be supported by incombustible construction or 
by the construction supporting the furnace which it serves, but in buildings of 
wooden construction a stack may be stayed laterally by incombustible stays 
to the wooden construction. A smokestack may be mounted directly upon 
and supported by the boiler or furnace which it serves if such boiler or furnace 
is designed and constructed to support safely the weight thereof. 

(c) The metal of a circular steel or sheet iron smokestack shall have not 
less than the following thickness: — 



Diameter of Stack. 



Thickness. 



Not more than 16 inches 

More than 16, not over 24 inches. 
More than 24, not over 30 inches . 
More than 30, not over 48 inches . 
More than 48, not over 60 inches . 



No. 10 Gage 
No. 8 Gage 
3/16 inch 
1/4 inch 
5/16 inch 



(130) 



Sees. 2105-2107 

(d) A smokestack may be mounted on the outside of a building sup- 
ported by and secured to the exterior wall thereof. If the wall is of com- 
bustible materials the stack shall be not less than four inches and not less 
than one third the stack diameter away and the wall for a width not less than 
twice the diameter of the stack shall be covered by one quarter inch of asbestos 
and sheet metal, or approved equivalent. 

(e) A smokestack inside a building shall be protected from contact with 
goods or persons by a substantial shield of incombustible materials, with 
provision for ventilating the space between stack and shield. If a smoke 
stack is within a ventilating shaft or other enclosure of a vertical opening, 
provision shall be made for ventilating the shaft or enclosure at the bottom 
and above the roof. Such enclosure shall be of incombustible materials and 
the stack shall stand clear of the enclosing walls on all sides. 

(f) A smokestack shall have at least four inches clearance from com- 
bustible material; such material within twelve inches of the stack shall be 
covered by one quarter inch asbestos and sheet metal or its approved equiva- 
lent and the space about the stack shall be ventilated. 

(g) Pertinent provisions for chimneys shall apply also to smokestacks. 

[ -\As amended by Ord. 1943, ch. 5 ] 

JSect. 2106. Smoke Pipes. — (a) Smoke pipes of metal shall be not 
less than number twenty-four gage copper-bearing, black or galvanized sheet 
iron, except that where gas is used for fuel, sheet copper weighing not less than 
sixteen ounces per square foot, or other approved material may be used. 

(b) Smoke pipes, where they connect with a chimney, shall be tightly 
fitted in a burned fire clay, cast iron or other substantial thimble built into the 
masonry, or a smooth-sided opening of brick or other masonry. 

(c) Smoke pipes of unprotected metal shall not be nearer than eighteen 
inches below exposed combustible construction unless the combustible 
material is protected by an incombustible shield having a width equal to twice 
the diameter of the pipe, suspended at least three inches below such combus- 
tible material and three inches above the pipe and ventilated on both sides. 
The space between a metal smoke pipe covered with not less than one and one 
half inches of asbestos or other approved insulation and combustible material 
above, or between a smoke pipe of unprotected metal and woodwork above 
protected by a ceiling of one-hour fire-resistive rating shall be not less than 
three inches. 

(d) Metal smoke pipes shall be at least twelve inches horizontally from 
combustible material unless protection and clearance are provided as speci- 
fied in paragraph (c) of this section. 

(e) If a masonry flue connects a furnace with a chimney or a stack, it shall 
be lined and otherwise constructed as specified for a chimney. 

[ %As amended by Ord. 1943, ch. 5 j 

*Sect. 2107. Fireplaces. — (a) Fireplace walls shall be not less than 
eight inches thick and if built of stone or hollow units shall be not less than 
twelve inches thick. The faces of such walls exposed to fire shall be lined 
with fire brick or other suitable fire-resistive material. When lined with four 

(131) 



Sees. 2107=2110 

inches of fire brick such lining may be included in the required minimum 
thickness. Every fireplace shall be connected to a chimney flue built as 
specified in section twenty-one hundred and two. 

(b) Fireplaces shall have hearths supported by trimmer arches or other 
approved fire-resistive construction. Trimmer arches and hearths shall be 
not less than twenty inches wide measured from the face of the chimney 
breast and shall extend not less than twelve inches beyond the fireplace open- 
ing on each side. Trimmer arches shall be of brick, stone or hollow tile not 
less than four inches thick, shall spring from the masonry supporting the 
fireplace and may thrust against the floor frame whether of wood or other 
material. A flat stone or reinforced concrete slab may be used to support a 
hearth instead of an arch if it is properly supported and a suitable fill provided 
between it and the hearth. Hearths shall be of brick, stone, tile or concrete. 
Wood centering under a trimmer arch shall be removed after the masonry 
has thoroughly set. No combustible materials shall be placed within three 
inches from the jambs or from the top or arch of a fireplace opening. 

(c) No heater burning solid or liquid fuel shall be placed in a fireplace 
which does not conform with the requirements of this section. The provi- 
sions of this section shall not be held to prevent construction without flue 
of a suitable foundation and wall protection, resembling a fire place for a gas- 
burning space heater; but if such construction has a flue, it shall conform in 
all respects to the provisions of this section for a fireplace. 

(d) Each fireplace shall have a separate and independent flue throughout 
its length to the open air. 

[ *As amended by Ord. 1943, ch. 5 ] 

Sect. 2108. High Pressure Boilers. — (a) Boilers generating steam 
at a pressure in excess of fifteen pounds per square inch shall be so located 
that no combustible material shall be less than two feet from the top or sides 
or ten feet from the front; and all combustible material less than four feet from 
the top or sides shall be protected by incombustible construction of at least 
one-hour fire-resistive rating and shall be well ventilated to prevent the 
temperature from rising above two hundred and fifty degrees Fahrenheit. 

(b) Steel, cast iron or reinforced concrete columns adjacent to such boilers, 
except columns which support only the boilers, shall not be in direct contact 
with boiler settings but there shall be an open and unobstructed space at 
least four inches wide for ventilation. 

Sect. 2109. Low Pressure Boilers. — Boilers generating steam at a 
pressure not over fifteen pounds per square inch, and hot water heaters not 
including domestic water supply heaters, shall have clearance from wooden 
partitions, ceiling and other combustible material, the same as specified for 
hot air furnaces in section twenty-one hundred and ten. 

fSect. 2110. Hot Air Furnaces. — (a) Hot air furnaces shall be en- 
cased in a metal or masonry shield with an air space between shield and fire 
box. Unless the shield over the top is double with an air space, the top of 
the furnace shall be covered with approved insulating material one inch thick. 

(132) 



Sees. 2110=2111 

(b) Combustible material placed within seven feet from a hot air furnace 
at the front or within two feet at the sides or rear shall be protected by sheet 
metal, or asbestos board, and if such material is within one foot from such 
furnace at the sides or rear, it shall be protected in the manner required in 
section twenty-one hundred and six for woodwork near a metal smoke pipe. 
The distance from the top of a hot air furnace to exposed combustible ma- 
terial above, within two feet laterally from such furnace and four feet in front, 
shall be not less than eighteen inches unless such woodwork is protected as 
provided in section twenty-one hundred and six for combustible material 
above a metal smoke pipe. 

[ fAs amended by Grd. 1943, ch. 5 ] 

JSect. 2111. Hot Air Pipes and Registers. — (a) Horizontal hot 
air furnace pipes shall be placed at least six inches below combustible material 
except that if such material is protected by metal lath and plaster or a loose- 
fitting metal shield or if the hot air pipe is covered with one half inch of corru- 
gated asbestos insulation, the clear distance may be reduced to three inches 
for portions of pipes within five feet from the furnace and to one inch for 
more distant pipes. 

(b) Hot air pipes passing through combustible partitions or floors either 
shall be double sheet metal pipes with at least one half inch air space or be 
covered with asbestos paper weighing not less than sixteen pounds per one 
hundred square feet. 

(c) No hot air pipes shall be placed in a wooden stud partition or wooden 
enclosure unless it is at least five feet horizontally from its outlet on the 
furnace. Hot air pipes in combustible partitions either shall be double with 
one half inch air space, or the space shall be lined with sheet metal or other 
incombustible material, or the pipe shall be covered securely with asbestos 
paper weighing not less than sixteen pounds per one hundred square feet. 
Hot air pipes in closets shall be not less than one inch away from woodwork 
or be double pipe with one half inch air space or be covered with asbestos 
paper weighing not less than sixteen pounds per one hundred square feet. 

(d) Every hot air furnace shall have at least one hot air pipe and register 
without damper, valve or louvres. 

(e) Where a register in the floor directly over a furnace is connected by 
a pipe from the top thereof, such pipe shall be double with not less than one 
inch ventilated air space and no combustible material shall be within three 
inches from the inner pipe. 

(f) Hot air registers placed in woodwork shall be surrounded with borders 
of incombustible material which shall prevent the register from coming in 
contact therewith. 

(g) Register boxes for warm air in wooden floors or partitions shall be made 
of sheet metal, double, with at least one half inch air space or shall be kept 
at least one half inch from woodwork and covered with asbestos paper weigh- 
ing not less than sixteen pounds per one hundred square feet. 

(h) The provisions of this section shall not apply to hot air pipes and 
registers from indirect low pressure steam or hot water radiators. 
[ JAs amended by Ord. 1943, ch. 5 ] 

(133) 



Sees. 2112-2114 

*Sect. 2112. Water Heaters and Hot Plates. — (a) Gas or electric 
domestic water supply heaters and gas or electric hot plates shall not be 
nearer than seven inches from a combustible wall unless the combustible 
material in the wall is protected by two inches clearance and sheet metal or 
its approved equivalent extending at least nine inches beyond each side and 
two feet above the apparatus. Wooden ceiling or shelving shall not be less 
than three feet above such apparatus. 

(b) Gas hot plates and electric hot plates or appliances of more than 
eighteen hundred watts capacity shall not be placed upon a wooden shelf 
or counter unless the appliance has a solid metal floor under the burners or 
heating elements, raised not less than two inches above the shelf, and the 
shelf is protected with sheet metal; or unless equivalent approved protection 
is provided. 

[ *As amended by Ord. 1943, ch. 5 ] 

fSect. 2113. Domestic Stoves and Ranges. — (a) Insulated or un- 
insulated stoves and ranges not of the flushback type used for heating rooms, 
water, or for the cooking or laundry of a family, whether burning solid, liquid, 
gaseous fuel or electricity shall not be placed within seven inches from a 
combustible wall. No wood or other combustible materials forming shelves, 
ceiling, cabinets or fixed furnishings shall be installed less than three feet 
above the top of stove or range or the uppermost oven of either, or within 
seven inches of the sides of ranges or stoves. Where incombustible materials 
are used for shelving — ceiling, cabinets or fixed furnishings — the minimum 
clearance above the top of range, stove or uppermost oven of either shall be 
eighteen inches and from the sides of range or stove, four inches. 

(b) Insulated Flushback Type Ranges or stoves may be placed directly 
against existing or new partitions, walls or other structure providing the 
entire wall, partition or structure is composed wholly of incombustible ma- 
terials. Arrangement of shelving, cabinets, ceiling and fixed furnishings shall 
be as mentioned in paragraph (a) of this section. 

(c) Combustion chambers of stoves or ranges burning solid or liquid fuel 
shall be connected to a chimney or a smokestack. Ovens and hoods of stoves 
and ranges may be ventilated to a chimney, smokestack, or ventilating duct. 
Such connections shall be of metal not less than number twenty-six gage 
thickness and wherever they pass through construction of combustible 
material they shall be encased in a sleeve of approved type which provides a 
clearance of at least three-fourths of an inch from any combustible material. 

[ \As amended by Ord. 1943, ch. 5 ] 

Sect. 2114. Commercial Stoves and Ranges. — (a) Stoves and ranges 
such as are used in kitchens of restaurants, hotels, clubs and similar estab- 
lishments shall not be placed nearer than twenty-four inches from a com- 
bustible wall unless the combustible material in the wall is protected by six 
inches clearance, not less than one-hour fire-resistive construction and a shield 
of metal or other approved incombustible material with free circulation of air 
between it and the wall, extending at least twenty-four inches beyond each 
side of the range and four feet above the top. 

(134) 



Sees. 2114=2117 

(b) Such stoves and ranges shall be provided with hoods of incombustible 
material connected by pipe or duct with an independent chimney flue or smoke 
stack extending above the roof. The hood, if of sheet metal or other simi- 
larly thin material, shall be separated from combustible material above by 
at least nine inches clearance, or by a ceiling of one-hour fire-resistive con- 
struction. The connecting pipe or duct shall be separated from combustible 
material as specified for smoke pipes in section twenty-one hundred and six, 
with one half the clearances there specified. 

Sect. 2115. Oil Burners. — Oil burners shall be installed in accordance 
with chapter one hundred and forty-eight of the General Laws and regulations 
issued thereunder. 

Sect. 2116. Incinerators. — (a) All incinerators, except those not 
exceeding four square feet in grate area, shall be constructed of brick masonry 
or reinforced concrete. The walls and roof shall be at least eight inches 
thick; if the area of the combustion chamber is fifteen square feet or more, 
the walls and roof shall be at least twelve inches thick. 

(b) The combustion chamber above the grate, and both above and below 
the grate in down-draft incinerators, shall be lined with fire brick laid in mor- 
tar or fire clay or with equally fire-resistive material. Fire brick lining may be 
included in the required wall and roof thickness. 

(c) If the smoke flue is used as a refuse chute, it shall be a smooth-lined 
chimney, vertical and directly over the combustion chamber. Charging 
hoppers shall be of approved design and construction and shall not project 
within the flue area. The area of charging opening shall not exceed one third 
the flue area nor shall the least dimension of the flue be less than three times the 
vertical dimension of the charging hopper. The top of the chimney shall be 
covered with a cage or screen of non-corrodible metal of approved design, and 
having an area not less than twice the flue area. 

Sect. 2117. Support of Heat Producing Apparatus. — (a) Except 
as otherwise provided in this section, heat producing apparatus whether 
electrical or by the combustion of solid, liquid or gaseous fuel shall be sup- 
ported upon a substantial foundation of incombustible and heat-resistive 
materials laid on the ground, or upon a floor of Type I construction. 

(b) Electrical appliances of less than eighteen hundred watts capacity 
shall not be subject to the requirements of this section. 

(c) Domestic stoves and ranges used for heating one room or for the 
cooking or laundry of one family, gas or electric water supply heaters, and 
heaters burning solid or liquid fuel for the domestic hot water supply of one 
family, may be supported upon floors of Type II or Type V construction with 
incombustible flooring. Such apparatus may be supported upon a wooden 
floor or combustible flooring, either; — 

(1) Where the apparatus has solid metal construction under the heating 
elements, fire or burners and ovens, not less than six inches above the floor 
and, except under gas or electric apparatus, with free circulation of air over 
the floor; or 

(135) 



Sees. 2117-2119 

(2) Where the floor is protected by sheet metal under and extending 
at least six inches beyond the sides and rear and at least twelve inches 
beyond the front of the apparatus and at least four inches of solid brick 
masonry or concrete under the apparatus; or with equivalent approved 
protection. 

(d) Stoves, ranges and coal or oil burning water supply heaters, for 
restaurants, hotels, clubs and similar establishments may be supported upon 
Type II or Type V construction with incombustible flooring, when the appa- 
ratus has solid metal construction under the fire, burners or other heating- 
elements and ovens, raised on metal legs not less than four inches above the 
floor with free circulation of air between. Such apparatus ma}' be supported 
upon a wooden floor or combustible flooring, either; — 

(1) Where the apparatus has solid metal construction under the fire, 
burners, or other heating elements and ovens, raised on metal legs not less 
than four inches above the floor with free circulation of air between, and 
the floor is protected with non-corrodible sheet metal under and extending 
at least six inches beyond the sides, rear and front of the apparatus and a 
baffle sheet of one half inch asbestos secured between two sheets of non- 
corrodible sheet metal under the entire apparatus suspended two inches 
below the floor thereof; or 

(2) Where the floor is protected by non-corrodible sheet metal under 
and extending at least six inches beyond the sides, rear and front of the 
apparatus, and hollow construction, under the apparatus, of brick on edge 
not less than four nor more than twelve inches apart, topped by reinforced 
concrete not less than three inches thick; or by equivalent approved pro- 
tection. 

(e) Heating apparatus such as down-draft and oil burning furnaces in 
which the floor of the combustion chamber rests directly upon a reinforced 
concrete or other structural floor, shall have a heat-resistive foundation, with 
ventilation and insulation if necessary, to prevent injury to structural metal 
or other materials in the floor. 

(f) Under boilers, furnaces and other heat-producing apparatus sup- 
ported upon a floor required by the provisions of Part 29 to be waterproofed, 
shall be installed insulation equivalent to that required for a wooden floor, 
to protect the waterproofing against damage from heat. 

Sect. 2118. Smoke Connection. — Every apparatus for the generation 
of heat by the combustion of fuel shall have suitable connection to an ade- 
quate chimney or smokestack except gas appliances exempted by the regu- 
lations for gas fitting issued under section one hundred and sixteen of Part 1 
of this code and other small apparatus of similarly intermittent use burning 
oil and generating not over twenty thousand British thermal units per hour, 
and except such apparatus in foundries, forge shops and similar establish- 
ments as shall be exempted with the approval of the commissioner. 

*Sect. 2119. Other Heat Producing Apparatus. — Other heat pro- 
ducing apparatus such as bake ovens, coffee roasting ovens, core ovens, 
japanning ovens, rendering furnaces, stereotype furnaces, wood-drying kilns, 

(13G) 



Sec. 2119 

annealing furnaces, charcoal furnaces, galvanizing furnaces, gas producers, 
smoke houses, forges and the like, shall be supported, and nearby woodwork 
and other combustible material shall be protected from such apparatus in the 
manner specified in this chapter for apparatus of similar size, temperature, 
and character of heat exposure. These and other special or uncommon 
sources of heat and flame shall be so constructed and protected as to prevent 
heating any wood or other combustible material used in the construction of 
floors, ceilings, partitions or other parts of a building, or required waterproof- 
ing, to a temperature over two hundred and fifty degrees Fahrenheit, when in 
full operation, and shall be so constructed as not to be liable to undue corro- 
sion or deterioration or to accidental overturn or other disarrangement con- 
ducive to danger. 

Every application for such permit shall be in writing, shall be filed with the 
commissioner and shall set forth the character of the building, the size, 
power and purpose of the apparatus, and such other information as the com- 
missioner may require. The commissioner may, after an examination of the 
premises described in the application, and after hearing the applicant and 
any objectors, issue a permit for placing this apparatus on such premises, upon 
such conditions as he shall prescribe, or he may refuse such permit. If the 
application is for anything other than a boiler or furnace the applicant shall 
publish in at least two daily newspapers published in the city of Boston, and 
on at least three days in each, and if so directed by the commissioner, shall 
also post conspicuously on the premises a copy of the application, and shall 
deliver copies thereof to such persons as the commissioner may designate. 

If no objection is filed with the commissioner before the expiration of ten 
days after the time of the first publication of notice, or within ten days of the 
delivery and first posting of the notice, if such delivery or posting is required 
the commissioner shall if the arrangement, location and construction of the 
proposed apparatus is proper and in accordance with the provisions of this 
act, issue a permit for the same. If objection is filed the application shall 
be referred to the board of appeal which may in its discretion require the 
deposit by the objector of a reasonable sum as security for the payment of 
the costs. 

After such notice as the board shall order it shall hear the same and shall 
direct the commissioner to issue a permit under such conditions as it may 
prescribe, or to withhold the same. If the permit is refused, the applicant 
and if it is granted the objectors shall pay such cost as the board may order. 

The commissioner may, from time to time, after public notice and hearing, 
prescribe the conditions on which furnaces, boilers, or other steam generators 
and hot water heaters may be maintained in buildings, and, if any person 
interested objects to such conditions and appeals from his decision establishing 
the same, the appeal shall be referred to the board of appeal, and thereupon 
said board shall prescribe the conditions. 

[ *As amended by Ord. 1943, ch. 5 ] 



(137) 



Sec. 2201 



PART 22. 
FIRE=RESISTIVE CONSTRUCTION. 

Section 

2201 — Determination of Fire=Resistance. 

2202 — Fire=Resistive Materials and Construction. 

2203 — Fire=Protection of Steel Columns. 

2204 — Fire=Protection of Cast Iron Columns. 

2205 — Fire=>Protection of Steel in Reinforced Concrete Columns. 

2206 — Fire=Protection of Steel Beams, Girders and Trusses. 

2207 — Fire=Protection of Steel in Reinforced Concrete Beams. 

2208 — Fire=Protection of Steel Reinforcing in Floors and Roofs. 

2209 — Fire=Resistive Floor and Roof Construction. 

2210 — Fire=Resistive Ceiling Construction. 

2211 — Fire=Resistive Bearing Walls and Partitions. 

2212 — Fire=Resistive Non=Bearing Walls and Partitions. 

2213 — Fire=Resistive Doors. 

2214 — Fire Door Construction. 

2215 — Fire=Resistive Shutters. 
2216 — Fire=Resistive Windows. 
2217 — Fire=Resistive Roof Covering. 

*Section 2201. Determination of Fire=Resistance. — (a) Materials 
of construction and fire-protective materials, and assemblies or combinations 
thereof, shall be classified for fire-protective and fire-resistive purposes in 
terms of their performance in authoritative tests made in accordance with 
Standard Specifications for Fire Tests of Building Construction and Materials 
of the American Society for Testing Materials, hereinafter called the Standard 
Fire Test. 

(b) The materials, assemblies and combinations of materials specified and 
listed in this chapter shall be assumed to have the fire-resistive rating here 
given. Other materials, assemblies and combinations shall be given fire- 
resistive ratings by the commissioner. Such ratings shall be determined by 
reasonable interpolation among the materials, assemblies and combinations 
listed and rated in this chapter, and by authenticated evidence of performance 
in standard fire tests, with such margin of safety as he shall consider necessary 
to provide for the exigencies of commercial production and field construction. 

(c) Where the interior of a building of Type III construction is of incom- 
bustible construction protected to provide one-hour fire-resistive rating, the 
exterior walls may be of two-hour fire-resistive construction. 

(d) Where the interior of a building of Type IV construction is of incom- 
bustible construction, the exterior walls may be of two-hour fire-resistive 
construction. 

(138) 



Sees. 2201=2202 

(e) In such group occupancies and where Type VI is allowed, but in no 
case over two stories in height, Type IV buildings may be constructed with 
their frames and exterior walls of incombustible construction. 

(f) All construction referred to in paragraphs (c), (d), and (e) shall be 
subject to the structural requirements of other parts of this code. 

[ *As amended by Ord. 1943, ch. 6 ] 

fSect. 2202. — Fire=Resistive Materials and Construction. — (a) 

Materials, to be given the fire-resistive ratings specified in this part, shall 
have the following minimum qualities: — 

(1) Concrete of Class 1 shall be so proportioned, in accordance with 
Part 26, as to have a strength of at least fifteen hundred pounds per square 
inch and the coarse aggregate shall consist of limestone, trap rock, blast 
furnace slag, cinders containing not more than twenty per cent of combus- 
tible material, burned clay or shale. 

(2) Concrete of Class 2 shall be so proportioned, in accordance with 
Part 26, as to have a strength of at least fifteen hundred pounds per square 
inch, the coarse aggregate consisting of sandstone, granite, quartzite, 
siliceous gravel or other similar material not over one inch in size. 

(3) Masonry shall consist of the materials specified in Part 24 laid in 
lime-cement or cement mortar, or approved masonry cement mortar, 
except that masonry of gypsum tile shall, and masonry of structural clay 
tile may, be laid in gypsum mortar. Masonry shall be thoroughly bonded 
by breaking joints in successive courses or by the use of metal ties. 

(4) Brick shall be burned clay or shale, concrete or sand-lime brick 
of Grade C or better as specified in Part 24. 

(5) Stone shall be limestone, marble, slate or equally fire-resistive natural 
stone. Sandstone, granite or other stone which, because of its crystalline 
structure or for other reason, is less fire-resistive, shall not be considered 
fire-protection for structural metal, but may be used in a masonry wall 
not less than twelve inches thick required to have fire-resistance. Stone 
masonry shall have the same fire-resistive rating as brick masonry. 

(6) Cast stone shall conform to the requirements of Part 24. Cast 
stone masonry shall have the same fire-resistive rating as brick masonry. 

(7) Concrete blocks, whether solid or hollow, shall have as coarse 
aggregate limestone, trap rock, blast furnace slag, cinders containing not 
more than twenty per cent of combustible material, burned clay or shale, 
and shall otherwise conform to the requirements of Part 24. 

(8) Structural clay tile shall conform to the specifications for load- 
bearing tile, floor tile or partition tile of Part 24. Where partition tile is 
specified, load-bearing tile may be used. 

(9) Gypsum tile or pre-cast gypsum concrete, whether solid or hollow, 
shall conform to Standard Specifications for Gypsum Partition Tile or 
Block of the American Society for Testing Materials and shall not contain 
more than three per cent by weight of wood or other combustible binder 
or filler. 

(139) 



Sec. 2202 

(10) Gypsum concrete shall not contain more than twelve and one-half 
per cent by weight of wood or other combustible binder or filler, and shall 
have a compressive strength of at least five hundred pounds per square 
inch as provided in Part 27. It shall not be used where exposed to the 
elements. 

(11 ) Expanded metal or wire lath as a base or reinforcement for plaster- 
ing shall weigh not less than two and two tenths pounds per square yard 
and shall have not less than two and one half meshes per inch. 

(12) Metal mesh reinforcement specified for masonry fire protection 
of structural metal shall consist of wire lath strips the full thickness of 
the masonry, laid in the beds thereof, or its approved equivalent. 

(13) Metal mesh reinforcement specified for concrete fire protection 
of structural metal shall consist of wire mesh weighing not less than one 
and one half pounds per square yard with wire spaced not over four inches, 
or not less than number eleven gage steel wire spaced not over four inches 
apart, or its approved equivalent. 

(14) Cement plaster shall be proportioned of one part Portland cement, 
and not more than two parts of sand measured by volume dry and loose 
to which may be added lime putty or hydrated lime not exceeding fifteen 
per cent of the cement. 

(15) Gypsum plaster, except where otherwise specified, may contain 
sand not in excess of three times the weight of the gypsum. 

(16) Lime plaster shall consist of a mixture of one part lime, not over 
three parts sand, and water. 

(17) Pneumatically projected mortar made of Portland cement, sand 
and water shall be rated for fire-protection the same as Class 1 concrete. 

(18) Concrete fill, where specified in this chapter in connection with 
hollow masonry units, shall consist of Class 1 or Class 2 concrete poured 
in the hollow spaces of the units as they are laid. 

(b) Portland cement concrete or gypsum concrete poured in place as 
fire-protection for beams, trusses and other horizontal or inclined members of 
structural steel and pneumatically projected mortar applied to structural 
steel as fire-protection shall be reinforced with metal mesh reinforcement. 
Concrete protection for vertical columns of structural metal shall have rein- 
forcing consisting of number five wire spaced not over eight inches apart or 
its equivalent. Reinforcement shall be wrapped around the structural 
member and so arranged as to be completely embedded in the fire-protective 
material and to ensure its integrity. 

(c) Plaster used as fire-protection or to resist the spread of fire shall be 
reinforced with metal lath, except plaster less than one inch thick on masonry 
or concrete. 

(d) In the protection of structural metal including reinforcement, one 
half inch of cement or gypsum plaster may replace an equal thickness of 
poured concrete or pneumatically projected mortar as protective material; 
and one inch of cement or gypsum plaster reinforced with metal lath may 
replace an equal thickness of poured concrete, pneumatically projected mortar 
or masonry protection. 

(140) 



Sees. 2202=2203 

(e) Where plaster is required without other specification, it shall consist 
of one half inch of cement or gypsum plaster, except that only gypsum plaster 
shall be used on gypsum masonry. 

(f) In this chapter, except where otherwise specifically stated, the thick- 
ness given in a list of materials applies to the next following item only, and not 
to the total thickness where additional materials are specified. 

(g) Pipes, wires, conduits and ducts shall not be embedded in or placed 
behind the fire-protective materials required for the protection of structural 
steel or iron except as otherwise provided in this paragraph. Above fire- 
protective hung ceilings and within the enclosed spaces in buildings of Type 
I and Type II construction, within which, other than the enclosure, fire pro- 
tection of steel is not required, as specified in Part 16, pipes, wires, conduits 
and ducts may be placed, provided they are so arranged and so secured that 
they will not, either by expanding in the event of fire, or otherwise impair the 
effectiveness of the enclosing protective materials. Electric conduits and 
wires and gas pipes may be embedded in concrete or masonry fire protection of 
structural steel where the protective material is reinforced with wire mesh, 
provided they shall have protective covering except over the tops of beams 
and girders, at least as thick as required for the steel. 

(h) In factories, garages, warehouses and other buildings in which the 
fire-protective covering required for steel or iron columns may be injured by 
the movement of vehicles, materials or equipment, the commissioner shall 
require such covering to be protected by metal or other material in a manner 
satisfactory to him. 

(i) Fire-stopping, for the purposes of this chapter, shall mean the stop- 
ping-off or enclosure at the ends and wherever else specified of the spaces 
between studs of partitions, joists of floors and roofs and other similar spaces 
to prevent drafts of air and the communication of fire from one such space to 
another. Fire-stopping shall consist of wood not less than one and one half 
inches thick, of sheet metal not less than twenty-four gage or of masonry, or a 
combination of such materials. Fire-stopping shall be tightly fitted in the 
space to be filled, about pipes, wires and ducts and if cut or disturbed in the 
placement of pipes, wires and ducts shall be repaired. 

[ fAs amended by Ord. 1943, ch. 6 ] 

JSect. 2203. Fire=Protection of Steel Columns. — (a) Structural 
steel columns required to have fire-protection of a given rating shall be 
covered on all sides with protective material having not less than the thickness 
necessary for the required rating. Except where "no fill" is specified, re- 
entrant and other accessible spaces behind the specified outer protection 
shall be filled with concrete or brick masonry or the material of the outer 
protection. 

(b) The following materials shall be assumed to afford to steel columns 
fire-protection of the rating indicated: 
Four-hour rating: 

(1) Two inches Class 1 concrete. 

(2) Three inches Class 2 concrete, metal mesh reinforcement. 

(3) Three and one half inches brick masonry. 

(HI) 



Sees. 2203=2204 

(4) Two layers two-inch structural clay partition tile masonry, metal 
mesh in beds. 

(5) Two inches structural clay partition tile masonry, concrete fill, 
metal mesh in beds, three fourths inch gypsum plaster. 

(6) Four inches structural clay partition tile masonry, concrete fill, 
metal mesh in beds, five eighths inch lime plaster. 

(7) Four inches structural clay partition tile or concrete block mason- 
ry, concrete fill, plaster. 

(8) Three inches hollow gypsum tile masonry and plaster. 

(9) Two inches gypsum concrete, metal mesh reinforcement. 

(10) Two inches solid gypsum tile masonry and plaster. 

(11) Three inches solid cinder concrete block masonry and plaster. 

(12) Four inches hollow cinder concrete block masonry and plaster. 

Three-hour rating: 

(13) One and three fourths inches Class 1 concrete. 

(14) Two inches Class 2 concrete, metal mesh reinforcement. 

(15) Two inches gypsum concrete. 

(16) Two inches solid cinder concrete block masonry and plaster. 

(17) Two inches structural clay partition tile masonry, concrete fill. 
Two -hour rating: 

(18) One and one half inches Class 1 concrete. 

(19) Two inches Class 2 concrete, metal mesh reinforcement. 

(20) One inch Class 1 or Class 2 concrete encased in standard weight 
steel or wrought iron pipe. 

(21) Two inches structural clay partition tile masonry and plaster. 

(22) Two layers plaster, each on metal lath, with three fourths inch air 
space between, two inches total thickness. 

(23) Two inch gypsum concrete. 

(24) Two inches solid or three inches hollow gj^psum tile masonry. 

One-hour rating: 

(25) One inch Class 1 concrete. 

(26) One and one half inches Class 2 concrete with metal mesh rein- 
forcement. 

(27) Two and one fourth inches brick masonry. 

(28) Two inches structural clay partition tile or concrete block masonry. 

(29) One inch cement or gypsum plaster on metal lath. 

(c) The thickness of protection on the outer edges of lugs or brackets 
need not exceed one inch. 

[ %As amended by Ord. 1943, ch. 6 ] 

*Sect. 2204. Fire=Protection of Cast Iron Columns. — (a) Cast 
iron columns required to have fire-protection of a given rating shall be covered 
on all sides with protective materials having not less than the thickness 
necessary for the required rating. Re-entrant spaces, if any, on the exterior 
of cast iron columns, and other accessible spaces behind the specified protec- 
tion, shall be filled with Class 1 concrete or brick masonry or the material 
of the outer protection. 

(142) 



Sees. 2204=2206 

(b) The following materials shall be assumed to afford to cast iron columns 
fire-protection of the rating indicated: — ■ 

Four-hour rating: — ■ 

Cast iron columns shall not be used where protection of four-hour rating is 
required. 

Three-hour rating: — 

(1) Two inches Class 1 concrete. 

(2) Three inches Class 2 concrete, metal mesh reinforcement. 

(3) Two inches structural clay partition tile or concrete block masonry, 
concrete fill. 

(4) One and one half inches cement or gypsum plaster on metal lath 
and metal furring to form one half inch air space. 

Two-hour rating: — ■ 

(5) One and one half inches Class 1 concrete. 

(6) Two inches Class 2 concrete with metal mesh reinforcement. 

One-hour rating: — 

(7) One inch Class 1 concrete. 

(8) One and one half inches Class 2 concrete with metal mesh rein- 
forcement. 

(9) One inch cement or gypsum plaster on metal lath. 

[ *As amended by Ord. 1943, ch. 6 ] 

fSect. 2205. Fire=Protection of Steel in Reinforced Concrete 

Columns. — (a) The main steel reinforcement, including spiral reinforce- 
ment and ties larger than one half inch, in reinforced concrete columns re- 
quired to have fire-protection of a given rating shall be covered with concrete 
having not less than the thickness listed in this section for the rating indi- 
cated: — 

Four-hour rating: — 

(1) One and one half inches Class 1 concrete. 

(2) Two inches Class 2 concrete. 

Three-hour rating: — 

(3) One and one half inches Class 1 or Class 2 concrete. 

Two-hour rating: — 

(4) One inch Class 1 concrete. 

(5) One and one half inches Class 2 concrete. 

One-hour rating: — ■ 

(6) One inch Class 1 or Class 2 concrete. 

(b) The thickness of protection on column ties not larger than one half 
inch may be one half inch thinner than that listed above. 
[ }As amended by Ord. 1943, ch. 6 } 

{Sect. 2206. Fire=Protection of Steel Beams, Girders and Trusses. — 

(a) Steel beams, girders and trusses or the members of trusses, required to 
have fire-protection of a given rating, shall be covered on all sides with ma- 
terial having not less than the thickness necessary for the required rating. 

(b) The following materials shall be assumed to afford steel beams, girders 
and trusses, or the members thereof, fire-protection of the rating indicated: 

(143) 



Sees. 2206=2207 

Four-hour rating: 

(1) Two inches Class 1 concrete. 

(2) Three inches Class 2 concrete. 

(3) Three inches structural clay partition tile or concrete block masonry 
and plaster. 

(4) Three inches hollow gypsum tile masonry and plaster. 

(5) Two inches gypsum concrete. 

(6) Two inches solid gypsum tile masonry and plaster. 

Three-hour rating: 

(7) One and three quarters inches Class 1 concrete. 

(8) Two and one half inches Class 2 concrete. 

(9) Two inches gypsum concrete. 

(10) Two inches structural clay partition tile, or concrete block masonry 
and plaster. 

(11) Two inches solid, or three inches hollow gypsum tile masonry. 

Two-hour rating: 

(12) One and one half inches Class 1 concrete. 

(13) Two inches Class 2 concrete. 

(14) Two inches gypsum concrete. 

One-hour rating: 

(15) One inch Class 1 concrete. 

(16) One and one half inches Class 2 concrete. 

(17) Seven eighths inch cement or gypsum plaster on metal lath. 

[ tAs amended by Ord. 1943, ch. 6 ] 

*Sect. 2207. Fire=Protection of Steel in Reinforced Concrete 
Beams. — (a) The main steel reinforcement, including stirrups larger than 
one half inch, in reinforced concrete beams, girders and trusses, including 
the ribs of reinforced concrete ribbed floors or roofs where one or both sides 
of the ribs, in addition to the soffit, are exposed to fire, required to have fire- 
protection of a given rating, shall be covered on all sides with concrete having 
not less than the thickness listed in this section for the required rating. Where 
a reinforced concrete floor or roof has a flush ceiling formed with approved 
permanent masonry fillers between ribs, the reinforcement shall have the 
protection required for reinforcing steel of floors and roofs in section twenty- 
two hundred and eight. 
Four-hour rating: — 

(1) One and one half inches Class 1 concrete. 

(2) Two inches Class 2 concrete. 

Three-hour rating: — 

(3) One and one half inches Class 1 or Class 2 concrete. 

Two-hour rating: — 

(4) One inch Class 1 concrete. 

(5) One and one half inches Class 2 concrete. 

One-hour rating: — 

(6) One inch Class 1 or Class 2 concrete. 

(144) 



Sees. 2207=2209 

(b) The thickness of protection on stirrups not larger than one half inch 
may be less than that listed by not more than one half inch. 
[ *As amended by Ord. 1943, ch. 6 ] 

fSect. 2208. Fire=Protection of Steel Reinforcing in Floors and 
Roofs. — (a) The steel reinforcement in reinforced concrete floors and roofs 
with flush or plane ceilings, such that the exposure to fire is on the soffit only, 
required to have fire-protection of a given rating, shall be covered with con- 
crete having not less than the thickness listed in this section for the required 
rating. In floors or roofs having reinforced concrete ribs where the concrete 
surrounding the steel reinforcement is exposed to fire on one or both sides in 
addition to the soffit, such reinforcement shall have the protection specified 
in section twenty-two hundred and seven for steel in reinforced concrete 
beams. 

Four-hour rating: — ■ 

(1) One inch Class 1 concrete. 

(2) One and one fourth inches Class 2 concrete. 

Three-hour rating: 

(3) One inch Class 1 or Class 2 concrete. 

Two-hour rating: — 

(4) Three fourths inch Class 1 concrete. 

(5) One inch Class 2 concrete. 

One-hour rating: — 

(6) Three fourths inch Class 1 or Class 2 concrete. 

[ \As amended by Ord. 1943, ch. 6 } 

{Sect, 2209. Fire=Resistive Floor and Roof Construction. — (a) 

Floors and roofs required to have resistance of a given rating to the spread of 
fire shall have such thickness of the materials of which it is constructed, as 
shall be necessary for the required rating, and structural metal forming a 
part of such floors or roofs shall have protection against fire of such required 
rating. Floors and roofs required to have two-hour or longer resistance to 
fire shall be constructed of incombustible materials. Granolithic, burned 
clay tile, ceramic tile or other similar incombustible floor finish of a given 
thickness may be substituted for an equal thickness, and sand, cinder or 
other incombustible filling material, with or without embedded wooden 
screeds, may be substituted for two thirds its thickness, of the floor or roof 
construction material specified in this section; provided, that such floors and 
roofs shall have adequate thickness for structural purposes. 

(b) The following floor or roof construction shall be assumed to afford 
resistance to the spread of fire of the rating indicated: 

Four-hour rating: 

(1) Four inches solid slab of reinforced Portland cement concrete or 
reinforced precast gypsum concrete. 

(2) Four inches solid masonry arches or slabs. 

(3) Four inches structural clay floor tile masonry arches or slabs with 
top covering of not less than two inches of solid masonry or reinforced 
concrete. 

(H5) 



Sees. 2209=2210 

(4) Five inches combination reinforced Portland cement concrete slab 
consisting of permanent fillers of concrete block, gypsum or structural 
clay tile and one and one half inches of concrete topping; but if structural 
clay partition tiles are used for fillers they shall be plastered on the soffit. 
Three-hour rating: 

(5) Three inches solid slab of reinforced Portland cement concrete or 
reinforced precast gypsum concrete. 

(6) Three inches solid masonry arches or slabs. 

(7) Four inches structural clay floor tile masonry, arches or slabs with 
top covering of not less than one and one half inches of solid masonry or 
reinforced concrete. 

(8) Four inches combination reinforced Portland cement concrete slab 
consisting of permanent fillers of concrete block, gypsum or structural clay 
tile and one-inch concrete topping; but if structural clay partition tiles 
are used for fillers, they shall be plastered on the soffit. 

Two-hour rating: 

(9) Two and one half inches solid slab of reinforced Portland cement 
concrete or reinforced precast gypsum concrete. 

(10) Two and one half inches solid masonry arches or slabs. 

(11) Three inches structural clay floor tile masonry, arches or slabs 
with top covering of not less than one inch of solid masonry or reinforced 
concrete. 

One-hour rating: 

(12) Three inches structural clay floor tile masonry, arches or slabs 
with all joints thoroughly filled with cement or gypsum mortar. 

(13) Wood floor or roof construction with joists not less than one and 
five-eighths inches in least dimension, fire-stopped, double board floor, 
approved asbestos felt between layers of boards, and with a ceiling of at 
least three quarters inch cement or gypsum plaster on metal lath. 

(14) Steel beams or steel joists not more than thirty-six inches apart 
on centers with incombustible floor and a ceiling of at least three fourths 
inch cement or gypsum plaster on metal lath metal furring. 

[ %As amended by Ord. 1943. ch. 6 J 

*Sect. 2210. Fire=Resistive Ceiling Construction. — (a) Ceilings 
required to afford fire-protection of a given rating to the floor or roof framing 
under which it is supported shall be of fire-resistive materials of at least the 
thickness necessary for the given rating. A fire-resistive ceiling and all 
hangers and fastenings necessary for its support to the protected framing 
shall be of incombustible materials. It shall be capable of sustaining its 
own weight without exceeding allowable stresses. Metal reinforcement in 
such a ceiling shall be protected from fire as specified in section twenty-two 
hundred and eight for reinforcing in a floor. 

(b) The following ceiling construction shall be assumed to afford to floor 
or roof framing fire-protection of the rating indicated:— 

Four-hour rating: — ■ 

(1) Two and one half inches solid slab of reinforced Portland cement 

concrete or reinforced precast gypsum concrete. 

(146) 



Sees. 2210=2211 

(2) Two inches precast reinforced gypsum concrete, plastered. 

Three-hour rating: — 

(3) Two inches solid slab of reinforced Portland cement concrete or 
reinforced precast gypsum concrete. 

(4) Two inches precast reinforced gypsum concrete, lapped or rabbeted 
joints. 

Two-hour rating: — ■ 

(5) One and one half inches solid slab of reinforced Portland cement 
concrete or reinforced precast gypsum concrete. 

One-hour rating: — 

(6) Three fourths inch cement or gypsum plaster on metal lath. 

[ *As amended by Ord. 1943, ch. 6 ] 

fSect. 2211. Fire-Resistive Bearing Walls and Partitions. — (a) 

Bearing walls and partitions required to have resistance to fire or the spread 
of fire of a given rating shall be constructed of fire-resistive materials and 
shall have at least the thickness necessary for the required rating. Walls 
required to have two-hour or longer rating shall be of incombustible materials. 
Steel reinforcement in reinforced concrete walls shall have the same protection 
for the given rating as is required in section twenty-two hundred and eight 
for steel in floors. 

(b) Bearing walls and partitions of the following construction and thick- 
ness shall be assumed to have resistance to fire and the spread of fire of the 
rating indicated: 

Four-hour rating: 

(1) Eight inches solid brick masonry. 

(2) Twelve inches hollow wall of brick masonry, minimum eight inch 
masonry thickness. 

(3) Twelve inches structural clay load-bearing tile masonry with two 
units and not less than three cells in the thickness of the wall. 

(4) Eight inches structural clay load-bearing tile masonry with one unit 
and not less than two cells in the thickness of the wall, plastered both sides. 

(5) Twelve inches concrete block masonry with one unit and not less 
than two cells in the thickness of the wall. 

(6) Eight inches one-piece concrete block masonry with shells and 
webs at least one and one half inches thick, plastered both sides. 

(7) Twelve inches total thickness of brick masonry facing bonded to 
structural clay load-bearing tile masonry backing. 

(8) Eight inches solid concrete. 

(9) Six inches solid reinforced concrete. 

(10) A steel or reinforced concrete frame bearing wall in which the 
steel has fire-protection of four-hour rating, with panel filling as specified 
in section twenty-two hundred and twelve for a non-bearing wall of four- 
hour rating. 

Three-hour rating: 

(11) Eight inches structural clay load-bearing tile masonry with two 
units and not less than four cells in the thickness of the wall. 

(147) 



Sees. 2211=2212 

(12) Twelve inches structural clay load-bearing tile masonry with one 
unit and not less than three cells in the thickness of the wall. 

(13) Eight inches one-piece concrete block masonry with shells and 
webs not less than one and one half inches thick, plastered both sides. 

(14) Eight inches one-piece concrete block masonry with shells and 
webs not less than two inches thick. 

(15) Five inches solid reinforced concrete. 

(16) A steel or reinforced concrete frame bearing wall in which the 
steel has fire-protection of three-hour rating, with panel filling as specified 
in section twenty-two hundred and twelve for a non-bearing wall of three- 
hour rating. 

Two-hour rating: 

(17) Eight inches structural clay load-bearing tile masonry with not 
less than three cells in the thickness of the wall. 

(18) Eight inches concrete block masonry with shells and webs not less 
than one and one half inches thick. 

(19) A steel or reinforced concrete frame bearing wall in which the 
steel has fire-protection of two-hour rating, with panel filling as specified 
in section twenty-two hundred and twelve for a non-bearing wall of two-hour 
rating. 

One-hour rating: 

(20) A steel or wooden stud bearing wall covered on both sides with 
one-inch cement or gypsum plaster on metal lath, fire-stopped, if of wood. 

(21) A steel or reinforced concrete frame bearing wall in which the 
steel has fire-protection of one-hour rating, with panel filling as specified 
in section twenty-two hundred and twelve for a non-bearing wall of one- 
hour rating. 

[ fAs amended by Ord. 1943, ch. 6 ] 

JSect. 2212. Fire=Resistive Non=Bearing Walls and Partitions. — 

(a) Non-bearing walls and partitions required to have resistance to fire and 
the spread of fire of a given rating shall be constructed of fire-resistive ma- 
terials and shall have at least the thickness necessary for the required rating. 
Walls required to have two-hour or longer rating shall be of incombustible 
materials. Steel reinforcement in reinforced concrete walls shall have the 
same protection for the given rating as is required in section twenty-two 
hundred and eight for steel in floors. 

(b) Non-bearing walls and partitions of the following construction and 
thickness shall be assumed to have resistance to fire and the spread of fire 
of the rating indicated: 

Four-hour rating: 

(1) Eight inches solid brick masonry. 

(2) Three and one half inches solid brick masonry, plastered both sides . 

(3) Six inches structural clay load-bearing tile, plastered both sides. 

(4) Six inches solid concrete. 

(5) Four inches solid reinforced concrete. 

(148) 



Sees. 2212=2213 

(6) Any wall which, as a bearing wall, has a three-hour or four-hour 
rating in section twenty-two hundred and eleven, except the steel or re- 
inforced concrete frame bearing wall. 

Three-hour rating: 

(7) Three and one half inches solid brick masonry. 

(8) Four inches structural clay load-bearing tile, plastered both sides. 

(9) Four inches solid concrete. 

(10) Three inches reinforced concrete. 

(11) Any wall which, as a bearing wall, has a two-hour rating in section 
twenty-two hundred and eleven, except the steel or reinforced concrete 
frame bearing wall. 

Two-hour rating: 

(12) Three inches gypsum tile masonry, plastered both sides except in 
exterior walls. 

(13) Eight inches structural clay partition tile masonry, plastered both 
sides. 

(14) Eight inches structural clay load-bearing tile, with three cells in 
the thickness of the wall. 

(15) Four inches concrete block plastered both sides. 

(16) Two inches solid neat, fibered, gypsum plaster on metal lath and 
incombustible studding. 

One-hour rating: 

(17) Three inches gypsum tile masonry. 

(18) Two inches solid gypsum tile masonry plastered both sides. 

(19) Three inches structural clay partition tile plastered both sides. 

(20) Two and one half inches solid cement or sanded gypsum plaster 
on metal lath and incombustible studding. 

(21) Three inches total thickness of hollow wall, three fourths inch 
cement or gypsum plaster on metal lath and incombustible studding. 

(22) Three inches total thickness of hollow wall, three fourths inch 
cement or gypsum plaster on metal lath and wooden studding, fire-stopped. 

[ XAs amended by Ord. 1948, ch. 6 ] 

*Sect. 2213. Fire=Resistive Doors. — (a) Doors which are required 
to be fire doors, fire-resistive doors, or of fire-resistive construction shall 
conform to the requirements of this section and section twenty-two hundred 
and fourteen. 

(b) Fire doors shall be classified for the purposes of this code as Class A, 
Class B, and Class C. 

(c) Class A fire doors shall be doors of the following construction as 
specified in Section twenty-two hundred and fourteen. 

(1) Tin-clad, three-ply wood core, sliding. 

(2) Tin-clad, three-ply wood core, swinging single leaf, doorway not 
over six feet wide. 

(3) Tin-clad, three-ply wood core, swinging in pairs, doorway not over 
ten feet wide. 

(149) 



Sec. 2213 

(4) Hollow metal, swinging single leaf, doorway not over four feet wide. 

(5) Hollow metal, swinging in pairs, doorway not over eight feet wide. 

(6) Sheet metal, sliding, single, doorway not over ten feet wide. 

(7) Sheet metal, sliding in pairs, doorway not over twelve feet wide. 

(8) Sheet metal, swinging single leaf, doorway not over six feet wide. 

(9) Sheet metal, swinging in pairs, doorway not over ten feet wide. 

(10) Steel rolling, doorway not over twelve feet wide. 

(11) Steel plate, doorway not over four feet wide. 

(12) Any other construction equal or superior to a tin-clad three-ply 
wood core door in a standard fire test, for resistance to fire, the spread of fire 
and smoke, and transmission of heat. 

(d) Class B fire doors shall be doors of the following construction as 
specified in section twenty-two hundred and fourteen. 

(13) Tin-clad, three-ply wood core. 

(14) Tin-clad, two-ply wood core, sliding, doorway not over ten feet 
wide. 

(15) Tin-clad, two-ply wood core, swinging single leaf, doorway not 
over six feet wide. 

(16) Tin-clad, two-ply wood core, swinging in pairs, doorway not over 
ten feet wide. 

(17) Hollow metal, sliding, doorway not over eight feet wide. 

(18) Metal-clad, paneled, swinging single leaf, doorway not over three 
feet wide. 

(19) Metal-clad, paneled, swinging in pairs, doorway not over six feet 
wide. 

(20) Any other construction equal or superior to a tin-clad two-ply 
wood core door in a standard fire test, for resistance to fire, the spread of 
fire and smoke, and transmission of heat. 

(e) Class C fire doors shall be doors of the following construction as 
specified in section twenty-two hundred and fourteen. 

(21) Metal-clad, paneled, swinging single leaf, doorway not over four 
feet wide. 

(22) Metal-clad, paneled, swinging in pairs, doorway not over eight 
feet wide. 

(f) A Class A door may be used where Class B or Class C is specified; 
a Class B door may be used where Class C is specified. Two Class B or 
Class C doors on opposite sides of the wall may be used where a single Class A 
or Class B door is specified. 

(g) Fire-resistive doors, when closed, shall completely cover the doorways 
in the walls and partitions or the openings in the floors or roofs to which they 
are fitted. A swinging fire door shall either overlap both jambs and the head 
of the opening not less than four inches or be fitted to a fire-resistive frame 
with a rabbet the full thickness of the door and with not less than one half 
inch overlap on the door. A sliding fire door, except in enclosures about 
passenger elevators, shall overlap both jambs and the head of the opening 
not less than four inches. A sliding fire door in an enclosure about a passenger 
elevator shall overlap jambs, head and adjoining panels not less than one 

(150) 



Sec. 2213 

half inch. Fire doors shall fit closely at the floor with clearance of not over 
one quarter inch. 

(h) In buildings with combustible floors, doorways required to have fire 
doors shall have incombustible thresholds the full thickness of the wall, extend- 
ing at least four inches from the face of the wall where a door is hung and 
extending laterally at least six inches beyond each jamb of the doorway. 
Thresholds may be flush with the floor. 

(i) The rabbeted frame of a swinging fire door shall be constructed of 
structural steel built into the concrete, masonry or other fire-resistive material 
of the wall about the opening and secured thereto, except that the rabbeted 
frame of a Class B or Class C door may be of wood, covered with sheet metal 
not less than twent}^-six gage in thickness, secured to the wall in the opening. 

(j) Fire doors when closed shall fit tightly against the wall or frame so 
as to provide an effective stop for fire and smoke. Except for the metal - 
covered wooden frame specified in this section, combustible material shall 
not intervene between the door and the fire -resistive material of the wall, 
floor or roof to which it is fitted. 

(k) Hinge hardware for fire doors shall be of malleable iron or rolled struc- 
tural steel not less than one fourth inch thick except that tubular steel track for 
sliding doors may be not less than one eighth inch thick. Equivalent thickness 
of solid bronze or brass may be used. Fire doors shall not depend upon cords, 
cables or chains to support them in closed position except in elevator shafts. 

(1) Tracks for sliding fire doors shall be so supported that a track hanger 
comes at each door hanger when the door is closed. Track hangers shall be 
secured to wood stud walls by screws or bolts, to steel stud walls by bolts or 
rivets, to masonry walls by through bolts and to concrete walls by through 
bolts or approved built-in inserts. Expansion shields shall not be used to 
support fire doors. 

(m) Hinges for swinging fire doors, except in wooden stud walls, shall be 
riveted or through-bolted to the structural steel frame of the opening, through- 
bolted to the wall if of masonry or concrete or secured by approved inserts 
in the concrete or built into masonry in approved manner. 

(n) Strap hinges and sliding door hangers shall be secured to fire doors by 
through-bolting, riveting or welding. Swinging fire doors in rabbeted frames, 
except tin-clad, wood core doors, may be hung on butts. Other swinging 
fire doors shall have strap hinges. 

(o) Sliding fire doors shall have adequate stops for the closed position. 
Swinging Class A fire doors shall have surface latches or unit locks. Class B 
and Class C doors shall have surface latches, unit or mortise locks. The 
latch bolts of unit or mortise locks on fire doors shall have a throw of three 
fourths inch. When mounted in pairs fire doors shall be rabbeted by means of 
an astragal or otherwise where they come together. One of a pair of swinging 
fire doors shall have push bolts at top and bottom with a throw of three 
fourths inch and the other shall be held by latch to the first. 

(p) Except in detention buildings, fire doors hung in required exits shall 
be so fitted with hardware that they can be opened from inside without use 
of a key when the building is occupied. 

[ *As amended by Ord. 1943, ch. J 

(151) 



Sec. 2214 

*Sect. 2214. Fire Door Construction.— (a) In the construction 
of fire doors solder shall not be used, except for filling joints. Sheet metal 
shall be fastened to wood by nailing and to metal frame by bolting, riveting 
or welding. 

(b) Class A doors shall not have glass panels. Class B doors may have 
glass panels not larger than one hundred square inches in exposed area nor 
more than twelve inches in width or height. Class C doors may have glass 
panels not larger than two thousand and sixteen square inches in total ex- 
posed area, and no single light shall have an exposed area exceeding twelve 
hundred and ninety-six square inches. Glass in fire doors shall be wire 
glass not less than one quarter inch thick and shall be set five eighths inch in 
grooves three quarters of an inch deep. 

(c) Fire doors shall be constructed as follows : — 

(1) Tin-clad, three-ply wood core doors shall be constructed in ac- 
cordance with the specifications of the National Board of Fire Under- 
writers for such doors in Class A openings, and shall bear the label of 
the Underwriters Laboratories to this effect. 

(2) Tin-clad, two-ply wood core doors shall be constructed in accord- 
ance with the specifications of the National Board of Fire Underwriters 
for such doors in Class B openings and shall bear the label of the Under- 
writers Laboratories to this effect. 

(3) Hollow metal doors shall have substantial stiles and rails of heavy 
pressed steel, reinforced for hinges and other hardware. Panels shall be 
of sheet steel filled with asbestos board or other approved insulating 
materials. The door shall be assembled by welding or riveting. 

(4) Sheet metal doors shall be constructed with a rolled steel rigid 
frame covered both sides with one sixteenth inch asbestos board and 
twenty-six gage corrugated sheet metal, with corrugations vertical on one 
side and horizontal on the other, bound on the edges with rolled steel or 
pressed steel shapes. 

(5) A steel rolling fire door shall be constructed of sheet steel inter- 
locking slats, sliding in grooves, counterweighted by springs, the roller and 
mechanism enclosed in heavy sheet metal. 

(6) A steel plate fire door shall be constructed of not less than twelve 
gage steel plate mounted on a rolled steel frame, assembled by welding or 
riveting. 

(7) A metal clad, paneled fire door shall have a wood core with stiles 
and rails not less than one and three fourths inches thick covered with 
twenty-six gage sheet steel; panels three fourths inch thick covered with 
twenty-six gage sheet steel, set three fourths inch in grooves; joints of 
metal lapped and well nailed. 

(d) A door properly bearing the Underwriters' Label certifying that it is 
suitable for the protection of a Class A opening shall be acceptable as a 
Class A door. 

(e) A door properly bearing the Underwriters' Label certifying that it is 
suitable for the protection of a Class B opening shall be acceptable as a Class 
B door, except that metal clad doors wider than three feet shall not be 
accepted as Class B doors. 

(152) 



Sees. 2214=2216 

(f) A door properly bearing the Underwriters' Label certifying that it is 
suitable for the protection of a Class C opening shall be acceptable as a Class 

C door. 

[ *As amended by Ord. 1943, ch. 6 ] 

Sect. 2215. Fire=Resistive Shutters. — Shutters required to be fire 
shutters or fire-resistive shutters shall be constructed and hung as specified 
for Class B fire-resistive doors in sections twenty-two hundred and thirteen 
and twenty- two hundred and fourteen. 

jSect. 2216. Fire=Resistive Windows. — (a) Windows which are re- 
quired to be fire windows, fire-resistive windows, or of fire-resistive construc- 
tion shall conform to the requirements of this section. 

(b) Fire-resistive windows may be fixed or arranged to open and close. 
Fixed fire-resistive windows shall be so secured in the walls in which they 
are placed that they may expand in case of fire without buckling. Movable 
fire-resistive windows shall be opened or closed in one of the following 
manners: — 

(1) One or more sashes may slide horizontally in a fire-resistive frame. 

(2) One or more sashes may slide vertically with counterweights or 
with two sashes counterbalanced and hung on chains. If a sash is closed 
in raised position it shall have a fastening. 

(3) A sash may be hinged at top, bottom, or either side. 

(4) A sash may be pivoted at top and bottom or at the sides. 

(5) A sash may be arranged to open and close in any other approved 
manner, with approved hardware. 

(c) Movable sashes in fire-resistive windows shall be fitted to fire-resistive 
frames of the same or similar construction. Both sashes and frames, and 
metal mullions between window units, shall be so fitted in the walls in which 
they are placed as to be continuous with the fire-resistive material of the wall 
and so secured that they may expand in case of fire without buckling. 

(d) Glass in fire-resistive windows shall be wire glass not less than one 
fourth inch thick and the area of a single light shall not exceed seven hundred 
and twenty square inches. Glass shall be set three eighths inch in grooves 
at least one half inch deep. Glass shall be secured by glazing angles or mold- 
ings screwed to the sash and forming continuous grooves for the glass. 

(e) Fire-resistive windows shall be of the following construction: — ■ 

(6) Hollow sheet metal sashes and frames fabricated by pressing, 
welding, riveting or crimping without the use of solder or other fusible 
alloy, except for filling joints, and bearing the label of the Underwriters' 
Laboratories. 

(7) Rolled steel or pressed steel sashes fabricated by pressing, welding, 
riveting or crimping, of a make and style approved by the commissioner. 

(8) Any other approved constructions as fire-resistive as that specified in 
paragraph (6). 

(f) Fixed fire-resistive windows of hollow sheet metal construction shall 
not exceed seven feet in width nor ten feet in height. Fire-resistive windows 
of hollow sheet metal construction with movable sashes shall not exceed six 
feet in width nor ten feet in height. 

(153) 



Sees. 2216=2217 

(g) Fire-resistive windows of rolled steel construction shall not exceed 
eighty-four square feet in area nor twelve feet in either height or width. 

(h) Fire-resistive windows and their fastenings shall be capable of resist- 
ing the wind pressure on the wall of the building applied either on the inside or 
the outside of the window without exceeding allowable stresses. 

(i) Where fire-resistive windows are required, wooden windows and plain 
glass may be substituted provided the openings are protected by fire-resistive 
doors or shutters, or, in buildings of approved occupancy and construction, 
by an approved system of open sprinklers. 

[ fAs amended by Ord. 1943, ch. 6 ] 

JSect. 2217. Fire=Resistive Roof Covering.— (a) Roof covering 
allowed under this code shall be classified as fire-retardant or ordinary, accord- 
ing to their resistance to fire outside, as provided in this section. Fire- 
retardant roof covering is the more fire-resistive and may be used on any 
building. Ordinary roof covering shall not be used where fire-retardant roof- 
ing is specified. Roof covering less fire-resistive than ordinary roof covering 
shall not be used on any building. 

(b) Fire-retardant roofing shall be any roof covering which meets the 
requirements of Class A or Class B roofing under the specifications of the 
Underwriters' Laboratories, Inc. The following roof covering shall be as- 
sumed to meet the requirements for fire-retardant roofing: — 

(1) Built up roofing consisting of successive layers of roofing felt im- 
pregnated with asphalt; a final layer of asphalt in which, while molten, is 
embedded a continuous layer of roofing gravel or slag. 

(2) Built up roofing consisting of successive layers of roofing felt im- 
pregnated with coal tar; a final layer of tar in which, while molten, is 
embedded a continuous layer of roofing gravel or slag. 

(3) Built up roofing consisting of successive layers of roofing felt impreg- 
nated with asphalt; a final layer of asbestos roofing felt impregnated with 
asphalt weighing not less than fourteen pounds per hundred square feet, 
or a final layer of asphalt-saturated prepared roofing coated with granu- 
lated slate or other similar material. 

(4) Built up roofing consisting of successive layers of roofing felt im- 
pregnated with tar or asphalt and a finish of burned clay floor tile, stone 
flagging, cement concrete or other similar material. 

(5) Sheet metal with locked and soldered joints not less than number 
twenty-six gage in thickness. 

(6) Shingles of natural slate . 

(7) Shingles of burned clay tile. 

(8) Shingles of sheet metal not less than number twenty-six gage in 
thickness. 

(9) Shingles of asbestos board not less than one eighth inch thick. 

(10) Shingles of asphalt saturated felt surfaced with granulated slate 
or other similar material and carrying the Underwriters Class "C" label. 

(11) Corrugated sheet metal with lapped joints not less than number 
twenty-six gage in thickness. 

(12) Corrugated asbestos board not less than three sixteenths inch 
thick. 

(154) 



Sec. 2217 

(c) Ordinary roofing shall be any roof covering which meets the require- 
ments of class C roofing under the specifications of the Underwriters' Labora- 
tories, Inc. The following roof covering shall be assumed to meet the require- 
ments for ordinary roofing: — ■ 

(13) Built up roofing consisting of successive layers of roofing felt 
impregnated with asphalt, coal tar or other approved material, not equal 
in fire-resistance to a fire-retardant roofing. 

(14) Prepared roofing consisting of felt or fabric impregnated or coated, 
or both, with asphalt, tar or other approved material or shingles of such 
prepared roofing, not equal in fire-resistance to fire-retardant roofing. 

(15) Canvas stretched tightly and coated with paint. 

(d) Built-up roofing shall be secured to the roof deck in the following 
manner: 

1 Over masonry slab. The first layer shall be laid in molten asphalt 
or tar mopped on the roof deck, after the deck is properly primed, or by 
nailing a layer of building paper to nailing inserts other than wood placed 
in the deck. 

2 Over wood decks the built-up roofing shall be secured by nailing a 
layer of building paper to the roof deck over which the prepared roofing 
is to be laid with the first layer laid in molten asphalt or tar. 

3 Roofings other than built-up roofings, such as shingles, slates, tile 
roll roofing shall be well secured to the deck by nailing, bolting, wiring, 
or other approved methods. 

[ tAs amended by Ord. 1948, ch. 6 and 9 ] 



(155) 



Sees. 2301-2303 



PART 23. 
LIVE AND DEAD LOADS. 

Section 

2301 — Design for Loads. 

2302 — Dead and Live Loads. 

2303 — Weights of Materials. 

2304 — Loads from Partitions. 

2305 — Live Loads on Floors. 

2306 — Special Concentrations. 

2307 — Partial Loadings. 

2308 — Impact. 

2309 — Lateral and Uplift Forces. 

2310 — Reduction of Live Loads. 

2311 — Roof Loads. 

2312 — Wind Loads. 

2313 — Load Tests of Structure. 

Section 2301. Design for Loads. — All buildings and parts thereof shall 
be designed to support the loads and withstand the forces to which they are 
subject, both dead and live, without exceeding stresses allowed for the various 
materials elsewhere in this code. 

Sect. 2302. Dead and Live Loads. — (a) The dead loads of a building 
include all the forces due to weight of the walls, permanent partitions, floors » 
roofs, framing, and all other permanent stationary construction entering into 
and becoming part of the building. 

(b) The live loads include all loads other than the dead loads. 
*Sect. 2303. Weights of Materials. — (a) The actual weights of the 
elements of construction and of materials to be supported shall be used in 
calculation of the loads. The materials listed in the following table shall be 
assumed to weigh not less than there indicated: — 

Pounds per 
Cubic Foot. 

Brick (face, sandlime, concrete) masonry 140 

Brick (common) masonry . . . . . . .120 

Cast iron 450 

Cast stone masonry 144 

Cinders, dry, in bulk 45 

Cinder fill 54 

Sand-cinder concrete, fill . . . 96 

Sand-cinder concrete, structural 108 

Stone or gravel concrete, plain 144 

Stone or gravel concrete, reinforced 150 

Common earth, dry and packed 100 

Wet mud 120 

Granite masonry 170 

(156) 



Sees. 2303-2305 

Pounds per 
Cubic Foot, 

Limestone masonry . , . . . . . . .160 

Marble masonry . 160 

Sandstone masonry 145 

Steel 490 

Timber 40 

Water 62.5 

Pounds per 
Square Foot. 

Plaster on metal lath exclusive of furring 8 

Roofing, tar and gravel 6 

[ *As amended by Ord. 1943, ch. 2 and Ord. 1955, ch. 2 ] 

fSect. 2304. Loads from Partitions. — (a) In buildings in which 
permanent partitions occur their weight shall be counted as affecting the 
design of all supporting structural members, including columns and founda- 
tions, as part of the dead load; and in those portions of office buildings in 
which the prescribed live load does not exceed fifty pounds per square foot, 
allowance for partition weight shall always be made, whether or not par- 
titions are shown on plans. 

(b) If a lay-out of partitions is included in the building plans, the weights 
of the partitions and their locations shall be determined in accordance there- 
with, or such lay-out shall be used to determine an equivalent load per square 
foot of floor to be applied uniformly as a superimposed dead load for purposes 
of design. But the allowance for partition weight in portions of buildings 
given to office occupancy, when expressed in pounds per square foot of floor, 
shall in no case be less than a minimum of two pounds for each foot of story 
height for each square foot of floor. 

(c) In estimating loading from actual weights of partitions it may be 
assumed that the partition occupies a space one foot wide, and a deduction 
may be made of the live load displaced on this width. 

(d) Arch action of partitions shall not be assumed to relieve the supporting 

members. 

[ fAs amended by Ord. 1943, ch. 6 ] 

JSect. 2305. Live Loads on Floors. — The live loads assumed on floors 
for purposes of design shall be the greatest loads that will probably be produced 
by the intended occupancies, but the following distributed live loads in 
pounds per square foot shall be taken as the minimum for the occupancies 
named, and for similar occupancies not listed which create or accommodate 
corresponding loadings. 

Pounds per 
Square Foot. 

Domestic Occupancy: all parts of private dwellings, rooms and suites 
in apartment houses, lodging houses and clubs; private, ward or dor- 
mitory rooms in hospitals, asylums, educational and religious institu- 
tions, including corridors giving access thereto; and bedrooms of 
hotels 40 

(157) 



Sec. 2305 

Pounds per 
Square Foot. 

Office Buildings: first and basement' floors 100 

Office Occupancy:* above first floor in office buildings, offices in other 

buildings, including corridors 50 

Church Auditoriums: with fixed seats, including aisles, sanctuary 

or chancel, sacristies, choirs and chapels 60 

Class Rooms: in schools and colleges, not exceeding nine hundred 
square feet in area, or larger size rooms where fixed seats are used; 
and school laboratories 50 

Theatre Auditoriums and Assembly Halls:* with fixed seats, 
including aisles and passageways 75 

Theatre Stages: gridirons and fly galleries 100 

Public Occupancy: lobbies, foyers, vestibules and similar public 
spaces of hotels, theatres, churches, clubs and public buildings; 
assembly halls, including class and lecture rooms exceeding nine 
hundred square feet in area, without fixed seats; dance halls, public 
dining rooms and restaurants, public rooms for social purposes, 
skating rinks, gymnasiums 100 

Bleachers: grandstands and temporary grandstands 150 

Corridors: 

In theatres and serving assembly halls 100 

In school buildings 75 

Other corridors, — same loading as heaviest occupancy to which 
they provide access. 

Fire Escapes and Exterior Balconies: 

In theatres and serving assembly halls 100 

In other buildings 75 

Stairs :* same loading as heaviest occupancy to which they give access, 
but maximum required 100 

Stores : 

For light merchandise, first and basement floors 100 

For light merchandise, above first floor, including mezzanine 75 

For heavy merchandise, all floors 125 

Storage: 

Light storage 125 

Heavy storage 250 

Manufacturing: 

Light manufacturing 75 

Intermediate manufacturing 150 

Heavy manufacturing 250 

Locker Rooms 75 

Stables 75 

* For special floor concentrations and lateral thrusts on stair and balcony rails, see sections 
2306 and 2309. 

(158) 



Sees. 2305-2306 

Pounds per 
Square Foot. 

Garages:* including Apparatus Rooms of Fire Stations: 

Class A — Floors used for vehicles exceeding twenty thousand 
pounds in weight, including load; and first or street floors of 
garages except those limited exclusively to passenger vehicles of 
not more than nine persons capacity . . , 250 

Class B — Floors not included in Class A and first or street floors of 
garages limited to passenger vehicles exclusively weighing not 
more than nine thousand pounds 150 

Class C — Floors above the first or street floors for passenger vehicles 

weighing less than six thousand pounds 100 

A floor connected directly with the street or by a ramp or driveway 
not more than eight feet high shall be regarded as a first or street 
floor. 

Hangars* 150 

Sidewalks* 250 

Driveways* 250 

Ceilings* — 

[ % As amended by Ord. 1943, ch. 6 ] 



§Sect. 2306. Special Concentrations. — In the design of floors, con- 
sideration shall be given to the effects of known or probable concentrations 
of load to which they may be subjected; and in buildings designed for the 
occupancies listed herein, floors shall be made capable of carrying the prescribed 
distributed loads or the following minimum concentrations, whichever may 
result in the greater stresses. The concentrations indicated shall be assumed 
to occupy spaces two and one half feet square, and so placed as to produce 
maximum stresses in the members affected. 

(1) For office floors, including corridors, a load of two thousand pounds. 

(2) For portions of garages subject to Class A loading, a concentrated 
load of twenty thousand pounds, and to Class B loading, ten thousand 
pounds. 

(3) For sidewalks, a concentrated load of eight thousand pounds. 

(4) For driveways, and for trucking spaces within the limits of a struc- 
ture a concentrated load of twenty thousand pounds. 

(5) For structural supports of ceilings under accessible spaces, for trap 
doors and skylights a concentrated load of two hundred pounds. 

(6) That portion of hangars subject to concentrated loads shall be 
designed to accommodate the heaviest vehicle housed therein. 

[ §As amended by Ord. 1943, ch. 6 J 

* For special floor concentrations and lateral thrusts on stair and balcony rails, see sections 
2306 and 2309. 

(159) 



Sees. 2307-2310 

Sect. 2307. Partial Loadings. — Consideration shall be given to the 
effects of partial as well as full live loading. 

Sect. 2308. Impact. — The live loads prescribed herein may be assumed 
to include a sufficient allowance to cover the effects of ordinary impact. 
For special occupancies and loadings involving unusual impacts, such as 
those resulting from moving machinery, elevators, craneways, and the like, 
provision shall be made by suitably increasing the assumed live loading. 

Sect. 2309. Lateral and Uplift Forces. — fa) In the design of base- 
ment walls and similar approximately vertical structures below grade, the 
forces due to lateral pressure of adjacent soil shall be calculated. Due allow- 
ance shall be made for possible surcharge from fixed or moving loads. When 
a portion or the whole of the adjacent soil is below a free water surface, cal- 
culations shall be based on the weight of the soil as diminished by buoyancy, 
plus full hydrostatic pressure. 

(b) In the design of basement floors and similar approximately horizontal 
structures below grade, the upward pressure of water, if any, in the supporting 
soil shall be taken as the full hydrostatic pressure applied over the entire area. 

(c) Balcony and stairway railings, exterior and interior, shall be designed 
to resist a horizontal thrust of twenty pounds per linear foot applied at the 
top of the rail. 

Sect. 2310. Reduction of Live Loads. — A reduction of the total 
live load to be assumed as affecting structural members supporting con- 
siderable tributary floor area, or supporting multiple floors, and also of the 
live load supported by flat and two-way reinforced concrete slabs, shall be 
permitted according to the following schedule. In this section the term 
"area tributary" to a supporting member means the load supported by the 
member, divided by the average load per square foot, and the reductions 
indicated are applicable to beams, girders, trusses, columns, piers, hangers, 
walls, and foundations. The "tributary area" for a flat or two-way slab is 
the area of a panel. No reductions shall be allowed in the roof load^as given 
in section twenty-three hundred and eleven, on any portion of a structure 
nor in the special concentrations specified in section twenty-three hundred 

and six. 

Per Cent Live Load Reductions. 



Occupancies for which 
Prescribed Live Load per 


In Members sup- 
porting Tributary 
Areas of More 
than — 


In Members supporting 
Stories to Number of — 


Square Foot is — 


100 
sq. ft. 


200 
sq. ft. 


300 
sq. ft. 


2. 


3. 


4. 


5. 


6 or 

more. 


125 pounds or less 


5 


5 


10 



10 


15 



25 

15 


15 

5 

25 


20 
10 

25 


30 
15 
25 


40 
20 
25 


50 


Over 125 pounds (except garages), 


20 
25 


Two-way and flat slabs, all occu- 
pancies. 





(160) 



Sees. 2311=2313 

Sect. 2311. Roof Loads. — (a) Flat roofs, and roofs having a rise 
of four inches or less per foot of run shall be designed to support a vertical 
live load of thirty pounds per square foot of horizontal projection. Roofs 
used as roof gardens, or for other such purposes shall be designed as floors to 
support the loads prescribed for corresponding occupancies. 

(b) Roofs having a rise of more than four and less than twelve inches per 
foot of run shall be designed for a vertical live load of fifteen pounds per square 
foot of horizontal projection, applied to the entire roof or to either of the slop- 
ing surfaces, whichever produces the greater stress, and a wind load as pre- 
scribed in section twenty-three hundred and twelve. 

(c) Roofs having a rise of twelve inches or more per foot of run shall be 
designed for wind load only, without other live load. 

*Sect. 2312. Wind Loads. — (a) All buildings shall be made capable 
of resisting horizontal wind pressures on their exposed vertical surfaces, and 
wind pressures normal to their sloping roofs without exceeding the stresses 
allowed in this act. 

(b) The overturning moment due to wind pressure shall not exceed two 
thirds of the moment of stability (as measured by the moment of the dead 
loads, about the leeward edge of the foundation or critical section at any 
other level) unless the structure is anchored to resist the excess overturning 
moment without exceeding the stresses prescribed. 

(c) The wind pressure on vertical plane surfaces other than signs shall be 
taken at ten pounds per square foot for those portions less than forty feet 
above the ground, at fifteen pounds per square foot for portions between 
forty and eighty feet above the ground and at twenty pounds per square foot 
for portions more than eighty feet above the ground. 

(d) The wind pressure on vertical plane surfaces of all signs shall be 
taken at fifteen pounds per square foot for those portions less than sixty 
feet above the ground, at twenty pounds per square foot for portions between 
sixty and eighty feet above the ground, and at a minimum of thirty pounds 
per square foot for portions more than eighty feet above the ground. The 
Commissioner may require a sign structure to be designed for greater pressure 
than the pressures given herein if in his judgment the exposure requires it. 

(e) For cylindrical surfaces the area exposed to wind shall be assumed 
as two thirds of the projected area. 

(f) On roofs having a rise of more than four inches per foot of run the 
wind pressure normal to the surface shall be taken as one and one half pounds 
per square foot for each inch of rise on one foot run, with a maximum pressure 
of twenty pounds per square foot when the rise exceeds twelve inches per 
foot. 

[ *As amended by Ord. 1943, ch. 6 and Ord. 1945, ch. 11 ] 

fSect. 2313. Load Tests of Structure. — (a) The commissioner 
shall have the right to order tests under load of any portion of a structure 
when the conditions have been such as to leave reasonable doubt as to the 
adequacy of the structure to serve the purpose for which it was intended. 
Such tests shall not be required to be made on any concrete or masonry 
construction until it is at least sixty days old. 

(161) 



Sec. 2313. 

(b) In such tests, the member or portion of the structure under test shall 
be subjected to a total load, including its own weight, which shall equal the 
total dead load plus twice the live load for which it is required to be designed. 
This load shall be left in position for a period of twenty-four hours before 
removal. The structure, if a floor or roof or portion thereof, shall be con- 
sidered to have passed the test if within twenty-four hours after the removal 
of the load such floor or roof recovers three quarters of the maximum deflection 
under the test load. If the member or portion of the structure shows evident 
failure or fails to meet the recovery requirement, such changes or modifications 
as are necessary to make the structure adequate for the rated capacity shall 
be made or, where lawful, and where the structure is undamaged, a lower 
rating may be established. 

[ ]As amended by Ord. 1943, ch. 6 ] 



(162) 



Sees. 2401-2402 



PART 24, 

MASONRY, 

Section 

2401 — Design of Masonry. 

2402 — Materials of Masonry. 

2403 — Brick. 

2404 — Stone. 

2405 — Cast Stone. 

2406 — Concrete Blocks. 

2407 — Structural Clay Tile. 

2408 — Gypsum Tile. 

2409 — Plain Concrete. 

2410 — Plain Gypsum Concrete. 

2411 — Mortar. 

2412 — Bond in Masonry. 

2413 — Allowable Unit Stresses in Masonry. 

2414 — Masonry Arches. 

2415 — Reinforced Masonry. 

2416 — Second=Hand Materials for Masonry. 

Section 2401. Design of Masonry. — Masonry shall be designed by a 
method admitting of rational analysis according to established principles of 
mechanics, supplemented by the assumptions herein specified, to support 
the loads and withstand the forces to which it is subject without exceeding 
the stresses allowed in this chapter for the various materials thereof. 

Sect. 2402. Materials of Masonry. — (a) The quality of materials 
assembled in masonry and the method and manner of their assembly shall be 
suitable for their use and shall conform to the minimum requirements of 
this chapter. 

(b) The materials entering into masonry shall be classified for the purposes 
of this code as follows: — 



(1) 


Brick. 


(2) 


Stone. 


(3) 


Cast Stone. 


(4) 


Concrete Blocks. 


(5) 


Structural Clay Tile. 


(6) 


Gypsum Tile. 


(7) 


Plain Concrete. 


(8) 


Plain Gypsum Concrete. 


(9) 


Mortar. 



(c) A material of masonry other than those classified in this chapter, 
which is incombustible and otherwise sufficiently embodies the characteristics 
of one of the materials here classified, and which satisfies the requirements of 

(163) 



Sees. 2402-2405 

this chapter for that material may be included by the commissioner in the 
classification of that material which it most closely resembles. 

(d) The commissioner may require reasonable tests from time to time of 
masonry to determine their quality and whether they conform to the require- 
ments of this chapter. 

(e) Tests of masonry or of the materials thereof shall be made in accord- 
ance with the standard specifications of the American Society for Testing 
Materials for testing the material in question and if for any material such 
standard specification is not available the commissioner shall specify the 
method and manner of making the test. 

*Sect. 2403. Brick. — (a) Brick, as' classified in this code, shall include 
masonry units usually about two and one quarter inches thick, three and 
three quarters inches wide and eight inches long. Brick shall be made of 
burned clay or shale, concrete, or a mixture of sand and lime. 

(b) Burned clay brick shall be either solid or hollow, but if hollow shall 
be at least three quarters solid. 

(c) Concrete brick shall be made of Portland cement, aggregates and 
water as specified for concrete in Part 26. 

(d) Sand-lime brick shall be made of sand, lime, and water well mixed, 
pressed and cured in a carefully controlled process to a uniformly hard and 
durable product. 

(e) Brick, whether of burned clay, concrete, or sand and lime, shall be 
classified for strength when tested flatwise according to the following table: — 

Classification of Brick by Strength. 



Grade. 


compressive strength 

(Pounds per Square 

Inch). 


Modulus of Rupture 

(Pounds per Square 

Inch). 




Average of 
Five Tests. 


Individual 
Minimum. 


Average of 
Five Tests. 


Individual 
Minimum. 


A 


4,500 or more 
2,500 to 4,500 


3,500 
2,000 


600 or more 
450 or more 


400 


B 


300 







(f) Brick for load-bearing masonry or masonry exposed to the weather 
shall be of Grade A or B. 

(g) Brick for fire protection, fire-resistive walls, or fire-stopping shall be 
of Grade B or better. 

[ *As amended by Ord. 1943, ch. 6 ] 

Sect. 2404. Stone. — Stone for masonry shall be hard and durable . 
Sandstone in masonry exposed to the weather shall be laid with its natural 
bed horizontal. 

fSect. 2405. Cast Stone. — (a) Cast stone shall be made of Portland 
cement, aggregates and water with or without admixtures. Cast stone for 
load-bearing masonry or exposed to the weather shall have an average com- 

(164) 



Sees. 2405=2407 

pressive strength at an age of twenty-eight days of at least five thousand 
pounds per square inch and shall have not more than seven nor less than three 
per cent water absorption by weight. 

(b) Cast stone shall not project more than six inches beyond the support- 
ing material. Cast stone shall have reinforcing as required for reinforced 
concrete in Part 26 of this code together with three inch damp-proofing 
protection of the reinforcing. 

[ \As amended by Ord. 1943, ch. 6 ] 

Sect. 2406. Concrete Blocks. — (a) Concrete blocks, as classified in 
this Code, shall include hollow masonry wall units of concrete made from 
Portland cement, water and suitable aggregates, such as sand, gravel, crushed 
stone, bituminous or anthracite cinders, burned clay or shale and blast-furnace 
slag. The materials shall conform to the requirements for the materials of 
concrete specified in Part 26 except that cinder aggregate for concrete blocks 
shall contain not more than twenty per cent of combustible matter. 

(b) Concrete blocks shall have outer shells at least five eighths inch thick 
and shall have strength in compression not less than two hundred and fifty 
pounds per square inch of gross area for an average of five blocks tested. 
Concrete blocks in load-bearing masonry or in masonry exposed to weather 
or soil shall have a strength in compression not less than one thousand pounds 
per square inch of gross area for an average of five blocks tested, and a mini- 
mum of seven hundred pounds per square inch for any block. 

(c) Concrete blocks exposed to weather or soil in masonry shall have not 
more than twelve per cent water absorption by weight. 

Sect. 2407. Structural Clay Tile. — (a) Structural clay tile shall con- 
sist of well burned hollow units of clay or shale. 

(b) Structural clay tile shall be classified for use as follows: — 

(1) Partition Tile. 

(2) Floor Tile. 

(3) Load-Bearing Tile. 

(c) Structural clay partition tile shall be classified for physical quality as 
Grade A or Grade B according to the following table:— 

Structural Clay Partition Tile. 





Grade. 


Water Absorption by Weight (per cent). 




Average of 
Five Blocks. 


Individual 
Maximum. 


Individual 
Minimum. 


A 


5 to 16 
10 to 25 


19 

28 


4 


B 


4 







(165) 



Sec. 2407 

(d) Structural clay partition tiles of the dimensions indicated shall have 
the construction and dry weights given in the following table:— 





Structural Clay Partition Tile. 




Dimensions (Inches). 


Minimum Number 
of Cells. 


Minimum Weight 
(Pounds). 


2x12x12 


3 
3 
3 
3 
4 
4 
4 
4 


14 


3 x 12 x 12 


15 


4x12x12 


16 


6x12x12 


22 


6x12x12 


25 


8x 12 x 12 


30 


10 x 12 x 12 


35 


12 x 12 x 12 


40 







(e) Structural clay partition tile shall not be used in load-bearing masonry. 
Partition tile exposed to the weather shall be Grade A. Partition tile in fire- 
resistive construction shall be Grade B or better. The exterior shells shall be 
at least five eighths inch and the interior webs at least one half inch thick. 

(f) Structural clay floor tile shall be classified for physical quality as 
Grade A or Grade B according to the absorption table of paragraph (c) of this 
section for Structural Clay Partition Tile. Structural clay floor tile used in 
floor and roof arches shall have at least the physical qualities of the tile here 
classified as Grade B, as provided in Specifications for Structural Clay Floor 
Tile of the American Society for Testing Materials. 

(g) Structural clay load-bearing tile shall be classified for physical quality 
as Grade A or Grade B according to the absorption table of paragraph (c) 
of this section, and the tile of each grade shall satisfy also the requirements 
for strength of the following table :— 

Structural Clay Load=Bearing Tile. 





Compressive Strength 
(Pounds per Square Inch op Gross Area). 


Grade. 


END CONSTRUCTION. 


SIDE construction. 




Average of 
Five Blocks. 


Individual 
Minimum. 


Average of 
Five Blocks. 


Individual 
Minimum. 


A 


1,400 or more 
1,000 or more 


1,000 
700 


700 or more 
700 or more 


500 


B 


500 







(h) Test3 to establish the grade of structural clay load-bearing tile shall 
be made as provided in Specifications for Structural Clay Load-Bearing Wall 
Tile of the American Society for Testing Materials. 

(166) 






Sees. 2407=2411 



(i) Structural clay load-bearing tile shall have the cellular construction 
and minimum weights given in the following table: — 

Structural Clay Load=Bearing Tile. 



Thickness in Wall (Inches). 


Minimum Cells in 
Thickness of Wall. 


Minimum Tile 

Weight per Square 

Foot (Pounds). 


4 


1 
2 
2 
2 
3 


20 


6 


30 


8 


36 


10 


42 


12 


52 







(j) Structural clay tile used in load-bearing masonry shall be load-bearing 
tile having at least the physical qualities of Grade B, and such tile in masonry 
exposed to weather or soil shall be of Grade A. Load-bearing tile shall have 
shells at least seven eighths inch and webs at least five eighths inch thick and 
shall otherwise conform to Specifications for Structural Clay Load-Bearing 
Wall Tile of the American Society for Testing Materials. 

*Sect. 2408. Gypsum Tile. — (a) Gypsum tile used for fire-resistive 
purposes shall conform to the provisions of Specifications for Gypsum Parti- 
tion Tile or Block and Specifications for Gypsum of the American Society for 
Testing Materials. 

(b) Gypsum tile shall not be used in load-bearing masonry or in masonry 
exposed to weather or soil. 

*Sect. 2409. Plain Concrete. — (a) Plain concrete is concrete cast 
in place and not reinforced, or reinforced only for shrinkage or changes of 
temperature. Plain concrete shall be mixed, placed and cured as specified 
for concrete in Part 26. 

(b) Plain concrete in load-bearing masonry or where exposed to soil or 
where used for fire-resistive purposes, shall be of such proportions as to have 
a strength of at least fifteen hundred pounds per square inch and where ex- 
posed to wetting or freezing at least two thousand pounds per square inch as 
provided in Part 26. 

[*As amended by Ord. 1943, ch. 6 and Ord. 1955, ch. 2} 

fSect. 2410. Plain Gypsum Concrete. — (a) Plain gypsum concrete 
may be used for fire protection and non -structural purposes and shall contain 
not over fifteen per cent by weight of wood or other combustible binder. 
[ ]As amended by Ord. 1948, ch. 6 ] 

JSect. 2411. Mortar. — (a) Masonry, other than plain concrete and 
plain gypsum concrete, shall be laid in mortar except stone masonry in under- 
water masonry, in retaining walls not in buildings which may be laid without 
mortar. Load-bearing masonry laid in mortar shall have full beds and full 
builds of mortar in which the units are placed. 

(167) 



Sec. 2411 

(b) Mortar shall consist of a mixture of suitable proportions of [Portland 
cement r lime, sand and water; but approved special masonry cement may be 
substituted for the Portland cement or lime, or both. 

(c) Portland cement and sand shall conform to the requirements for these 
materials in Part 26 of this code. Lime shall conform to Specifications for 
Quicklime for Structural Purposes or Specifications for Hydrated Lime for 
Structural Purposes of the American Society for Testing Materials. 

(d) Lime putty shall be made by slaking to a smooth paste fresh and 
properly burned quicklime. The resultant paste shall be stored in a suitable 
box or other receptable for not less than forty-eight hours before being mixed 
with sand. Hydrated lime may be substituted in equivalent amount for 
lime putty. 

(e) Lime mortar shall be composed of one part of lime putty and not 
over three parts of sand by volume. Portland cement may be added to 
lime mortar, replacing an equal volume of lime putty, and when the cement 
is not less than one half the lime by volume, the working stress allowed in 
the masonry may be increased proportionally up to the stress specified for 
lime-cement mortar. 

(f) Lime-cement mortar Class A shall be composed of one part of lime 
putty, one part of Portland cement and not more than six parts of sand by 
volume. Portland cement may be added to lime-cement mortar replacing 
an equal volume of lime putty, and when such addition is made, the working 
stress allowed in the masonry may be increased proportionally up to the 
stress specified for cement mortar. 

(g) Lime-cement mortar Class B shall be composed of two parts lime 
putty, one part of Portland cement and not more than eight parts of sand by 
volume. Portland cement may be added to lime-cement mortar replacing 
an equal volume of lime putty, and when such addition is made, the working 
stress allowed in the masonry may be increased proportionally up to the 
stress specified for cement mortar. 

(h) Cement mortar shall be composed of one part of Portland cement 
and not more than three parts of sand by volume with an allowable addition 
of lime putty or hydrated lime not to exceed fifteen per cent by volume of the 
cement content. 

(i) Mortar made of so-called "Masonry Cement" may be used. The 
unit stress allowed in masonry laid with such mortar shall be determined by 
the commissioner after tests or other satisfactory evidence have been sub- 
mitted to him, but the unit stress shall not be greater than that given in 
section twenty-four hundred and thirteen for masonry laid in lime-cement 
mortar. 

(j) In proportioning mortar a sack of Portland cement weighing about 
ninety-four pounds shall be taken as one cubic foot and the volume of the 
sand shall be based on dry and loose measurement. 

(k) Except as otherwise provided in paragraph (a) of this section load- 
bearing masonry, party walls, fire walls and masonry exposed to weather or 
soil shall be laid in lime mortar, lime-cement mortar, cement mortar or 

(168) 



Sees. 241N2413 

approved masonry cement mortar. Hollow masonry walls and masonry of 
hollow units shall be laid in lime-cement mortar, cement mortar or approved 
masonry cement mortar. Masonry likely to be under water or in contact 
with wet soil, if laid in mortar, shall be laid in cement mortar. Mortar or 
grout under metal bases of columns or beams resting upon concrete shall be 
made without lime. 

(1) Gypsum tile walls and other non-bearing masonry walls may be laid 
in gypsum mortar. 

[ |As amended by Ord. 1943, ch. 6} 

Sect. 2412. Bond in Masonry. — Masonry walls and piers shall be 
bonded as provided in Part 14. 

*Sect. 2413. Allowable Unit Stresses in Masonry. — (a) In ma- 
sonry walls and piers subject to axial loads the average unit compressive 
stress shall not exceed the values given in the following table: — 



Average Unit Compressive Stress in Masonry. 

(Pounds Per Square Inch, Gross Area.) 



Masonry. 


Lime 
Mortar. 


Lime-Cement Mortar. 


Cement. 


Class A. 


Class B. 


Mortar. 


Brick: 

Grade A 


100 

75 

300 

100 


200 
150 

450 

200 
100 

80 
80 


180 
130 

400 

180 

90 

70 
70 


300 


Grade B 


225 


Cut Stone: 

Granite 
Limestone 1 


600 


Marble j ' 

Sandstone j 

Cast Stone \ 




Rubble Stone / 

Concrete Blocks 


300 
150 


Structural Clay Tile: 

Load-Bearing Tile 


100 


Floor Tile 


100 







The compressive unit stress in plain concrete shall not exceed one fifth the 
compressive strength at twenty-eight days when determined as specified 
in Part 26. 

(b) The unit shear in masonry shall not exceed one tenth the allowable 
unit compressive stress. 

(c) The maximum unit stress in bending in sound natural stones used in 
lintels, foundations, retaining walls and elsewhere shall not exceed the values 
given in the following table: — 

(169) 



Sees. 2413=2416 

Maximum Unit Stress in Bending. 
[Pounds Per Square Inch.] 

Granite 180 

Limestone 140 

Marble 120 

Sandstone 100 

The maximum unit stress in bending in plain concrete shall not exceed one 
fiftieth the compressive strength at twenty-eight days when determined as 
specified in Part 26. 

(d) The unit bearing stress in masonry under supported beams, columns 
and other concentrations, and the maximum unit stress in masonry walls and 
piers including stress due to calculated bending and eccentric loading shall 
not exceed by more than twenty-five per cent, the allowable average stresses 
given in this section. 

(e) In hollow walls or in masonry of hollow units, solid masonry shall be 
provided under concentrations of load to transmit the load without excessive 
stress. 

(f) Masonry bearing walls shall have at least the thickness specified in 
Part 14. 

[ *As amended by Ord. 1943, ch. 6 ] 

fSect. 2414. Plain Masonry Arches. — (a) Masonry arches shall be 
so designed that the line of thrust under all loadings lies within the middle third 
of the structural arch, or arch ring. Abutments shall be provided capable of 
resisting the horizontal as well as the vertical component of the thrust without 
settlement which would permit the line of thrust to depart from the middle 
third of the arch ring. 

(b) The horizontal component of the arch thrust may be resisted by 
metal ties so placed that the horizontal component furnished by the ties com- 
bined with the vertical supporting reaction shall be in line with the arch 
thrust. 

(c) In the design of tie rods and beams to resist the thrust of successive 
masonry floor arches, the load producing the thrust shall be considered to be 
the live load for interior panels and the total load for exterior panels. 

[ fAs amended by Ord. 1943, ch. 6 ] 

JSect. 2415. Reinforced Masonry. — Lintels in masonry walls, and other 

approved structures, may be constructed of reinforced masonry when designed 

and constructed in a manner consistent with the provisions of Parts 26 and 28 

of this code. 

[ f As amended by Ord. 1943, ch. 6 ] 

Sect. 2416. Second=Hand Materials for Masonry. — Second-hand 
brick, stone, blocks and other masonry units shall not be used in masonry 
unless they conform to the requirements of this code and have been thoroughly 
cleaned. 



(170) 



Sees. 2501=2502 



PART 25. 
WOOD. 

Section 

2501 — Design of Wood, 

2502 — Quality of Lumber. 

2503 — Lumber Sizes and Grades. 

2504 — Allowable Unit Stresses in Wood. 

2505 — Wooden Columns. 

2506 — Wooden Beams. 

2507 — Wooden Floors and Roofs. 

2508 — Wooden Walls and Partitions. 

2509 — Wood Framing. 

Section 2501. Design of Wood. — (a) Structures of wood shall be 
designed by methods admitting of rational analysis according to established 
principles of mechanics, supplemented by the assumptions herein specified, to 
support the loads and withstand the forces to which they are subject without 
exceeding the stresses allowed in this part for the various grades and species 
of wood. 

(b) Wooden structural members shall be so framed, tied, braced and 
anchored as to develop the strength and rigidity necessary for the purposes 
for which they are used. 

(c) Walls and partitions of wood shall conform to the provisions of Part 14. 
Floor and roof construction shall conform to the provisions of Parts 16 and 
17 respectively. Wood near chimneys and heating apparatus shall con- 
form to the provisions of Part 21. 

(d) Except as otherwise provided in Part 29, wood shall not be used in 
the foundation of a structure. Except as otherwise provided in Parts 14, 16 
and 17, wood shall not be used to support masonry. 

Sect. 2502. Quality of Lumber. — Structural wood of the species 
listed in the tables of allowable unit stresses in section twenty-five hundred 
and four shall conform to the requirements for the several grades in specifica- 
tions or grading rules of regional associations of lumber manufacturers which 
are based upon the grading procedure of American Lumber Standards in 
Simplified Practice of the United States Department of Commerce and the 
Guide to the Grading of Structural Timbers and the Determination of Work- 
ing Stresses (Miscellaneous Publication No. 185 of the United States De- 
partment of Agriculture). The lumber of the several grades and species 
shall be so specified as to justify the allowable stresses in accordance with 
the said Guide to the Grading of Structural Timbers and the Determination 
of Working Stresses. 

(171) 



Sees. 2503=2504 

*Sect. 2503. Lumber Sizes and Grades. — (a) The minimum sizes 
of structural members of wood specified in this part refer to net sizes, 
for which American Lumber Standard dressed sizes shall be accepted as 
minimum. For convenience nominal sizes may be shown on the plans sub- 
mitted with applications to the commissioner for permit, provided that com- 
putations of stresses in wood members used structurally shall be determined 
by the net finished sizes of lumber and timber employed. The actual di- 
mensions of greater rough and/or dressed sizes of lumber supplied may be 
computed for strength provided such sizes are specified or shown on the 
drawings. 

(b) The species, classification and grade of all wood used structurally 
shall be specified on the drawings filed with the commissioner. 

[ *As amended by Ord. 1943, ch. 6 ] 

fSect. 2504. Allowable Unit Stresses in Wood.— (a) The unit 
stress in wooden structural members of the several species and grades shall 
not exceed the allowable values specified in the following tables computed 
on the net cross section, except stresses due to wind impact and temporary 
loads and as otherwise provided in this section. 

[The tables which in law follow here are, for typographical 
reasons, reproduced on pages 178 to 181, inclusive.] 

The working stresses listed in the tables are allowed for lumber in con- 
tinuously dry locations, for pressure impregnated lumber and timber with 
approved preservative toxics, and for wet timbers below mean low water 
level. Compression across the grain in untreated lumber used in damp 
locations, alternately wet and dry or wholly wet shall not exceed seventy 
per cent of the values shown in Table I. In structures such as bridges in 
the open, trestles, towers and reviewing stands, the allowable unit stresses, 
except for shear and rigidity, in untreated lumber and timbers shall be re- 
duced to eighty-five per cent of the unit stresses listed and in untreated 
structures more or less continuously damp or wet such unit stresses shall 
not exceed seventy-five per cent. 

(b) Except for form-work, sewer and trench dynnage and other tem- 
porary purposes, sheathing, inaccessible attic joists, lumber and timber 
used structurally or for load bearing purposes shall be of the grades and 
species listed in accompanying Tables I and II and their corresponding 
allowable unit stresses, in pounds per square inch, computed on the basis 
of actual dimensions, shall not be exceeded except as herein modified for 
impact, wind, etc. Those species, grades and corresponding stresses not 
included in Tables I and II shall be established by the commissioner on the 
basis of miscellaneous publication now known as No. 185 "Guide to the 
Grading of Structural Timbers and Determination of Working Stresses" 
and supplement thereto of the United States Department of Agriculture. 

(172) 



Sec. 2504 

(c) In wooden members subject to axial tension the tensile stress shall 
not exceed the allowable stress in bending. Compression parallel to the 
grain shall not exceed the stress allowed in short columns. 

(d) The unit stress in wooden structural members due to wind alone or 
in combination with static live and dead loads shall not exceed by more than 
one half the allowable stresses specified in this section. 

(e) When the unit stress in wooden structural members due to impact 
does not exceed that due to static live load the members need not be increased 
in size on account of impact. When the stress due to impact exceeds that 
due to static live load, the unit stress in the member due to impact and dead 
load combined shall not exceed the allowable stresses specified in this section. 

(f) All structural lumber shall be grade marked or other evidence satis- 
factory to the commissioner shall be submitted verifying its appropriate 
grade. Salvaged lumber, if it meets grading requirements, may be used. 

(g) Temporary Structures. 

1. In temporary structures and structures subject to loading for short 
periods allowable stresses may be exceeded by not more than fifty per 
cent in the discretion of the commissioner. 

2. In joists supported on a ribbon or ledger board and spiked to the 
studs, the allowable unit stress in compression across the grain may exceed 
the allowable stresses specified in this section by not more than one half. 

3. The unit stress in compression across the grain in a limited area 
not over six inches long along the grain nor less than three inches from the 
ends of the timber may exceed the allowable stresses specified in this 
section by not more than the following percentages: 



Length of Bearing (Inches). 



Percentage Excess. 



1/2 

1 

1 1/2 

2 

3 

4 

6 or more . 



85 
60 
45 
30 
15 
10 
None 



Intermediate values shall be determined by interpolation. The bearing 
stress under a washer or small plate shall not exceed that provided in this 
paragraph for a bearing the length of which equals the diameter of the 
washer or plate. 

4. Temporary structures as considered above shall be removed within 
one year. 

(173) 



Sees. 2504-2505 

(h) Unit compressive stress on a surface inclined to the grain shall not 

exceed the following value: — 

CQ 

C Sin 2 $ + Q cos 2 Q 

in which (C) is the allowable unit compression parallel to the grain. 
(Q) is the allowable unit compression across the grain. 
{0) is the angle between the direction of the pressure and the direc- 
tion of the grain. 

(i) The allowable unit shear specified in this section is based upon the 
maximum amount of checking, due to shakes or seasoning, permitted by the 
grading rules for each species. Lumber with greater checking than is per- 
mitted in the grading rules may be used in structures with the approval of the 
commissioner, provided the unit shear is proportionately less than the allow- 
able values specified in this section. 

(j) The unit shear in joint or connection details of wooden trusses or 
framing may exceed the values specified in this section by not exceeding fifty 

per cent, 

[•\As amended by Ord. 1943, ch. 6 and Ord. 1955, ch. 2} 

JSect . 2505. Wooden Columns. — (a) The average unit compression 
in wooden columns axially loaded shall not exceed the values specified in 
section twenty-five hundred and four, depending upon the ratio of length to 
least net dimension. Intermediate values shall be determined by inter- 
polation. The ratio of length to least dimension shall not exceed fifty. 

(b) The axial load on a wooden column of round cross-section shall not 
exceed that allowed on a square column of the same cross-sectional area. 

(c) The least lateral dimension of a tapered column for determining its 
slenderness ratio shall be measured at a point one third the length from the 
small end but shall not be taken as more than three halves the least dimension 
at the small end. The average unit compression at the small end shall not 
exceed the allowable stress for a short column. 

(d) Built up wooden columns of several adequately seasoned pieces shall 
have each well spiked, screwed, glued, or bolted together with approved 
mechanical connectors. Solid laminated columns shall have boards or planks 
coverplated securely to the edges of all laminations. 

(e) In a built up wooden column subject to axial load the average unit 
compression shall not exceed three quarters of the allowable stress specified 
in section twenty-five hundred and four nor shall its load exceed the allowable 
load of a solid rectangular wooden column of which the moment of inertia 
about each principal axis is equal to the sum of the moments of inertia of the 
several pieces of the built up column about corresponding axes. 

(f) Wooden columns and posts shall be squared at the ends at right angles 
to their axes. 

(g) Wooden columns resting upon concrete or masonry which is in contact 

with the ground shall be separated from such concrete or masonry by an 

effectual seal to prevent moisture from reaching the wood through capillary 

action. 

[ %As amended by Ord. 1943, ch. 6 ] 

(174) 



Sec. 2506 

*Sect. 2506. Wooden Beams. — (a) In computing the maximum unit 
shear in wooden beams the effect of loads not further from the center of the 
support than the depth of the beam may be neglected. 

(b) Wooden beams notched at the end supports shall not be so loaded 
that the unit shear exceeds the allowable value specified in section twenty-five 
hundred and four when computed by the following formula — 

3 Vh 



2bd 2 
in which (V) is the shear. 

(h) is the total depth of the beam, 
(b) is the breadth of the beam. 

(d) is the depth of the beam from the bottom of the notch to the 
opposite face. 

(c) Unless the local unit stress is calculated and found to be not in excess 
of allowable stresses specified in section twenty-five hundred and four, wooden 
beams shall not be cut, notched or bored to clear pipes, wires, conduits or 
for other purposes except as follows: — 

(1) Notches may be cut in the top or bottom not deeper than one 
fifth the depth of the beam and not further from the support than one 
fifth the span. 

(2) Holes may be bored in the middle third of the depth and length 
not larger in diameter than one quarter the depth. 

(3) Holes may be bored elsewhere in the piece limited as to size and 
placement the same as knots in the grade of lumber used, having due 
regard to the existence of knots in the piece. 

(d) Trimmers, tail joists and headers more than eight feet long or more 
than four feet long where the live load exceeds fifty pounds per square foot 
unless framed on top of supporting beams, shall be hung in approved stirrup 
irons or joist hangers. 

(e) In wooden floor and roof construction where the depth of joists is 
more than three times the thickness, and where the span is greater than eight 
feet, bridging shall be placed between joists not less than eight feet apart 
nor less than eight feet from supports. Cross-bridging shall not be less than 
two square inches in net cross-section; and where the live load is greater 
than fifty pounds per square foot, not less than four square inches. 

(f) Joists doubled under bearing partitions shall be well spiked together 
or separated by solid bridging not more than sixteen inches apart. 

(g) Beams built up of timbers shall be firmly bolted together. Bolts 
shall be staggered and spaced longitudinally not further apart than four 
times the depth of the beam. 

(h) Where wooden girders or beams meet at columns they shall be fitted 
around the columns or butted up close, and unless the post caps or bolsters 
provide sufficient anchorage, shall be held in place and tied through to form 
a continuous tie across the building sufficient to resist the wind pressure 

(175) 



Sees. 2506=2507 

specified in Part 23 applied outwardly to the walls. Where wooden beams 
are supported by girders they shall be tied to form a similar continuous tie 
across the building. 

(i) Wooden beams or girders resting upon masonry walls, or parallel to 
masonry walls, and nailing pieces for planking or boarding supported by 
masonry walls, shall be bolted or otherwise anchored to the walls in such a 
manner as to resist the wind pressure specified in Part 23 applied outwardly 
to the walls. 

(j) Joists supporting a live floor or roof load not more than forty pounds 
per square foot and supported at the ends by a wooden girder, may rest upon 
a wooden strip or cleat, not less than one and one half by three and one half 
inches, well spiked or otherwise secured to the girder. Such joists supporting 
heavier loads shall rest on top of the girder or be hung in approved joist 
hangers. 

(k) Nailing strips for the support of wooden joists or planking on a steel 
girder or beam shall be bolted to the web of the girder or beam. Where the 
live load exceeds forty pounds per square foot the nailing strip shall be bolted 
to the girder or beam and shall rest upon the flanges or upon shelf angles 
attached to the web which provide a three-inch bearing or upon other approved 
support. 

(I) The ends of wooden beams or girders resting upon masonry or concrete 
exterior, party or fire walls shall be separated from the opposite face of the 
wall and from beams entering the opposite face of the wall by at least four 
inches of solid masonry or concrete. 

[ *As amended by Ord. 1948, ch. 6 ] 

Sect. 2507. Wooden Floors and Roofs. — (a) Wood shall not be used 
in the first floor of a building where there is not a basement or cellar below, 
unless it has clearance above the ground of at least twenty-four inches, and the 
space below is ventilated either to a heated basement or to the outside air. 
Ventilation of such space to a heated basement shall consist of at least two 
remote openings in the basement wall having a total area of at least two square 
feet for each twenty-five linear feet of wall. Ventilation of such space to 
outside air shall consist of one or more openings in each exterior wall thereof, 
well distributed, except that openings need not be provided in the front wall 
when the space is ventilated in the rear and both side walls. The aggregate 
area of openings shall be not less than two square feet for each twenty-five 
linear feet of wall. Openings in exterior walls shall be protected by non- 
corrodible wire mesh with openings not greater than one half inch. 

(b) Rough or sub-floor boards in buildings of Type IV or Type VI shall 
be laid across the joists at an angle of not less than forty-five degrees. Each 
board shall be nailed twice at each joist. The sub-flooring shall extend to 
and be fitted to the rough walls and partitions. 

(c) Floor boards and planking shall not penetrate a party or fire wall nor 
extend through a doorway in a party or fire wall. Roof boarding and planking 
shall not penetrate or extend over a party or fire wall. 

(176) 



Sees. 2508=2509 

jSect. 2508. Wooden Walls and Partitions. — (a) Wooden stud 
bearing walls shall be designed to support their vertical loads without assist- 
ance from boarding or other wall covering. Bridging and other bracing shall 
be provided as may be necessary for this purpose and otherwise as provided 
in Part 14. 

(b) Floor or roof girders, hip and valley rafters framing on exterior stud 
walls shall be supported by adequate posts. 

(c) Stud partitions containing plumbing, heating or other pipes shall be 
so framed and the joists beneath so spaced as to provide proper clearance for 
the piping. Where a partition containing such piping is parallel to supporting 
floor joists, the joists shall be doubled under the partition, spaced to clear the 
piping and bridged with solid bridging. 

(d) All concealed openings through floors shall be fire-stopped as provided 
in section 2202, paragraph (i) of this code. 

ft As amended by Ord. 1943, ch. 6 ] 

Sect. 2509. Wood Framing. — (a) In bolted connections of wooden 
trusses or framing the center of a bolt shall not be less than twice its diameter 
from the edge of the member. In the direction of the force transmitted the 
distance from the edge shall be such that the unit shear shall not exceed 
the allowable shear specified in section twenty-five hundred and four. The 
bolt shall fill the hole completely without splitting the timber. Bolts with 
rolled threads shall not be used in shear. Bolt threads shall be full and 
clean and of sufficient length to allow the nut to be screwed up tight. Washers 
shall be used under nuts and, except on carriage bolts, under heads. Nuts 
shall be concentric. 

(b) Timber joints in which other fastening devices and connectors are 
used shall be designed and framed in accordance with good engineering 
practice. 



(177) 



03 

A 

<! 
O 

• 5 

S « 



U3 




o 




z 


Ph 






tt 


«a 


Ct^ 


r/> 


o 


H 

03 


£ 


►H 

o 


1 


t-3 


1 


03" 


UJ 


«* 


03 


w 






pq 



►J 

H 
Q 

& Q 



3 
H 





MH 
















°s« 


© 





O 













oo.t: go *-■ 








O 













P 3 £ 








O 













,— 1 -r-l r* -+^> 
























O 


0* 
















O 


CO 








3 

a 





(N 

1— I 


CO 


r-l 


I-H 


CO 

I-I 




• r-l 
































el fl 














0) 
CO 


g.2 'g 





O 


O iC 1O1O 


O 


O 


o»o»o 







O 


00 "# IN IN 


O 


O 


00-* (N 


0) 

52; 


<N 


CO 


00 CO CO CO 


CO 


CO 


CO CO CO 








. > 




■ V 

























•cj s** 


O 


OO 


OOOO 


OCN 





000 






O 


(NO 


(NO OO 


t»iO 





(NOO 


D 1 
CO 


1—1 


1-1 1-1 


1-1 rH 




7-1 


Hrtrt 


M 
















0> 






























CO 


^^-^ 














*d 


,0 

















a a *\i 


O 


OO 


OOOO 


OO 







OOO 





O 


OO 


OOOO 


OO 


■* 


OOO 


P-t 


llfl 


O 


Tfl I-H 


00 CO (NO 


1—1 O 





00 COIN 




1-1 


l-l T-l 


tH 1— 1 I-* 


1—1 


I— 1 


rH r-l i-l 




^s^S 
















<# 














H 








a 
"00 

GO 


a 







ci 






^05 




«►§ R 


00 

go 

<3 




J3 


< 


CQ 

<3 




3*1 

f « 3 
55 


00 
CI 

a 


00 

a* 05 
P< 00 

. 00 


"00 

00 

<! 

4^> . 

00 00 

03 a 




GO 

a 

a 

(H 


0) 

S 

(1 S3 


P 


D 


00 -., 

H)H 


O 


5 GO 




N 


CoJ^ 


£ 


» 


^* 


^<5 








_G0 


T3 






►h 






f-a 3 


0) 






<! 




■73 




C 






ERCI. 
ADE 

MES 




05 -# 


-5 °3 


•a 

150 


PI 


e3 

13 +^ 




M 


Ph 




u 


§ « *< 




-r= 

L* a 

T3" 


-is-* 5 Ra 


3+^ 
Iff 


3 

a 

S 


3 3 
■*> u 
O += 
3^hCO 







"e8 

2 




COcO«m«*-i 


J3CO 
co«« 


*< cS — 

co 5 






3 


00 
00 


^^^ 

mrnOO 


JS 





^"S a 

.2 s a 
•3*0 

cocoO 




co 


i-H rH 


H CO i-i 


ojo 
CO 


£ 








t5 














c 














(H 














bO 














ai ' 




♦♦1 








** 


1 s 

S 




* 








OO 









Species and 

Stress 
Grades 




OO 
TJHrH 


QO 


** 





T3 






T3 


M-, (+-( C*H «4H 


00 
00 


1— 1 


*a 





O 


OOOO 


I-I 


GO 

c3 




CD 
CD 


0> • 

00 cu 


0> 


0) 


u 


OOOO 
CO CO (NO 

O 

go 


(h 
00 

s 




00 


H 
co 

CO 


<5H 


M 







OOO 

OOO 
OOCD<N 




ti 


Ah 


K-PCO 













O 


0<! 


Ha 


h 




Q 


po 


S 


S 


rt 




H 


>* 


ou 


a 


H 


•< 






O 


O 


Q 


n 


n 


H 



(178) 



© 


o 




o 


O 


o 


o 


o 


o 




o 


O 


o 


o 


o 


o 




o 


o 


o 


o 


o 


o" 




o" 


o" 


© 


o 


o 


o 




o 


o 


o 


o 


K3 


CO 




CO 


e* 


°i 


CN 


iH 


l-H 




l-H 


rH 


1-1 


j-T 


o 


o 




o 


o 


t^ 


o 


o 


00 




00 


o 


CO 


«3 


»o 


CO 




CO 


CO 


<N 


CN 


oooo 


o 




o 


<*tH 


OOO 


OOO 


CNtNCNO 


o 




o 


COCO 


OOOOt^ 


000 GO 


■ — 1 1— I > — 1 1 — I 






1-1 








OOOO 


oo o 


o o 


O O OOO 


oo 


OOO 


ooo 


oooo 


oo o 


o «a 


O O OiOO 


oo 


OOO 


ooo 


00CD">* CN 


000 CO 


Ttf o 


CO *# <NOO 


oo 


CO-tfCN 


(NrH© 


rtrtHH 


CNl-t l-l 


1-1 l-H 


l-H l-l •— i I— i 


1-1 














•xi 














% 






Hard- 
tnber 
on 




Ms 

" (3 45 


si 
fj 


o . 
O CO 


a 

e8_, O 


^ d 

(4 {J 

® O 

™ 03 


National 
wood Lu 
Associati 




Southern 
Inspectio 
eau of th 




Californi 
Redwood 
Associati 


rd . 

+i CQ 

S-< !i 

£2 






ructural or > 
L. Dimension 
L. 1050 #f Dim'n. 


a d* 








CD 


a 


. Edge & Sound 
o. 1 Structural 
ense Dimension 
imension 
ense 1050 #f Di 
ed. Gr'n. 900 # 








Red & Whit 

a u 


Structural 

'ble " or 
q. Edge & Sou 


do 


Close grain 
sl'ct. AU-Ht. 
ll-Heart 


4) 

w 

a 
to 

"(-13 3 

to 


«*H *+-l *4H *t-i 




^Zppp^ 

• oa --h >-h <n cn 

r -1 d • • • • 

H 4) O O O O 




«»-,to<< 


<+-l t*H 4-H 


OOOO 


+3 v&ai 
o d ° . 

cd a 6?— ' 


I-Hl-HCN 


0003 

oo 


^ 4) +a 

o 52 o 

O 4) 


OOO 


oooo 


odd 


oo 


OOO 


00cO"tftN 

rtrirtrt 


4) >-'ierl -^> 
toP-:i<3to 


£££ 


SQfcfcfcfc 


OOl 


©n 4) 

r-i P to 


(Ni-iO 
i-( i— 1 1— i 








4) 4) 














0} CO 










4> 




« * 3 5* 










fi 3 3 
45 


3 * 


0) a) 
P P 




.9 






P 




tH MH *WIH*W 


*"«« 


'3 s 3 


«4-**4-l «+-» 




IfH lu •+-♦ 


•41 «*H 


=*t= * *** 


*=* 


t-l 
M 

4) 
CO 

Os 3 

6 


*** 


800 #f 
600 #f 
400 #f 
200 #f 


2000 # 
1800 # 

1600 # 


o o 
o >o 
-* o 

l-H 1-1 


o o OOO 

© © OiOO 
CO r)( CN003 
,-H i-l l-H rH 


So 

Ooi 


OOO 
OOO 

«hO 

I— I I— 1 l-H 








psi 








CD 

12 






<1 


o 

H 

i— i 


ooo 

ooo 


a 

M 

4) 
+i 
(A 

03 

W-3 


P 
■« 


11 




2 S 


CO t^cN 
P 


H3 

K 
< 


5 ° 
g to 




O 

o 

P 


I- 1 S 


O 


1-4 




& 


ft 


3 


to 






(179) 





CO 

p 




3 




o 




H^ 




H 


tn 


55 


c/v 
t/J 


pi 


Ctf 


w 


H 


Ph 


c/5 


| 


a 


CO 


z 


ri 
w 


* 




Ctf 


w 


o 


2 


£ 


55 




O 




M 


1 


co 


u 


CO 

H 


w 


« 


03 




£ 


o 


D 


U 


J 


•8 




co 


J 


2! 


< 


s 


of 


p 


3 


i-i 

o 


H 


O 


u 




1 — ) 


r/3 


mJ 


H 


u 


CO 


e/) 


O 

Ph 
1 




1 
CN* 




H 




h1 




pq 




«! 




H 





o 


CD 


CN 


IO 


. 


CO 


CN 




"5 


O 


eo 


r- 


CN 


o 


^ 






fi 


i—i 


f=H 


i— t 


1-t 


f=l 


M-.*3 

0_* 


Q 


o 


CO 


■<* 


00 


o 


CO 


u «o 


"«* 


t~ 


o 


t> 


00 


"* 


CN 


^> 


i-H 


CN 


CN 


l-H 


CN 


CN 


o 
















iO 


CO 


00 


00 


CO 


CO 


l-H 




CO 


CM 


CO 


iO 


Tt< 


i-H 


OJ 


CO d 

H S 

8 J 


CN 


CN 


CO 


CN 


CO 


CN 


o 

CO 


rt* 


IO 


N 


iO 


00 


CO 


Q 

02 r- 1 


O 


CO 


00 


CO 


"* 


OS 


CO 


CO 


"* 


CO 


■>SH 


CO 


T3^ 
d S 






























3 C4 




o 


CO 


o> 


CO 


Ci 


N 


o <u 


co 


o 


00 


•«# 


■* 


■^i 


CN 


f^HH* 

.S3 

c +3 


CM 


■* 


■* 


CO 


•* 


IO 


*o 




OS 


<N 


Ot-i— 1 IO 


rj< 


IO 


CO 


"3 ao 
H d 


CO 


i—i 


CN 


CNCNi-HO 


IO 


i-H 


t~ 


CN 


CO 


CO 


00 00 00 1> 


»o 


CO 


CO 


boS 
















oP 

■^fH 


















00 


CN© 


©COI>CO 


i-H 


o 


i-h00tJ( 


"3.2 


O 
CN 


CO 


CNO0 


CO 00 COO 


i-H 


CO 


Ot>-iO 


^ 1 


CO 


00 1> 


OOSOIN 
i— 1 


CO 


co 


00 00 00 


U 1 
















Ph o 






























d - M 




CO 


COlO 


00 00»OI> 


CO 


00 


OCNi-H 


t>. 


t-H 


ooo 


lOOO^HCO 


"5 


00 


CO COb- 


i-H 


t» 


ooo 


i-HOOOO 


CO 


CO 


i-HOOS 


$°2 

CO 






1—1 


T-Hi-lr-l 






tH tH 


s- m 
















a o 




<N 


ON 


IO00OO 


00 


CO 


IO i-H i-H 


15 


•* 


CO 


1-HlHH 


CO-* CO CO 


l> 


o 


CNCN-* 


i— 1 


t^ 


i-H C3> 


CNi-HOOO 


CO 


l> 


MHO 






1—1 


rH i-t i-H 






i-H i-H i-H 




o 


oo 


oooo 


o 


o 


COOO 




O CO 


o 


oo 


OOO00 


o 


CN 


OOO 




*d O 


00 


CN© 


COCNi-HOO 


N 


N 


TttCNi-H 




co a 




i— 1 i-H 


i-Hi-H i-H 






i-H i-H i-H 






CO 










U 


d 


CO 






. 




Rules 
Under Whic: 
Graded 


"co 

CO 

< 

d 

a 

p 
b 


p . 

o2 

Ceo 

KPh 

Oh 

co< 


CO 

coWO 

o H S 

F-nfflO 
cogO 

gpco 


WPh 

a . 

WQ 

OO 


d 

CO 
CO 

< 

CO 

d 

a 

u 

rO 

Hi 

o 


PhO 

p^<j 






Q 














P* 










j 




Pi 








* 


ERCIA 
ADE 

MES 






^Soo-2 


*3 

d 


d 
.2 


o3 
f-. 

(-i o 

d d 


§ "3d 




Q 


■p-p t. 2 

O O <D d 


o 


"oQ 

d 




o 

O 


13 

s 


OO 


CD d,0 CD 

co co£^ 


d 

M 

CO 


CD 

a 

s 


d^co 

t-r 03 n 

CO d g 




o 

d 


o© 


g§HH 


CD 


r-< 


° 2 d 

CD d B 




tn 


o o 


O r — ' O O 




o 


13^ o 

cocoO 




+3 

co 


CNO 
i— 1 1— I 


QcoZ£ 


CO 


fc 






OO 


C3 












^^fc 


(H 




o 






O 


oo 


0,0 




* 






* 


oo 


co . 


O 


o 




CO 

H 

c^P 


o 
o 

00 


CNO 

T-H-H 


d ffi 
CD CO 

QO 


o 


CN 


OO 

** 




oooo 


o 


•ts 


Ooo 
JLOO 

^CNi-H 


T3 


Q 


^^^^ 




c3 


CO Ph 


CD 




oooo 


d 


O 


<o Hri 


HO 

1— I 


Ph 


Ph 


OOO00 
COCNt-100 


CD 


o 

HP 


co _i 
rjH d 


CO K 
H 
SQ 


d 

u 

CO 

+=> 
co 

CD 

Ph* 


P5 

p 

co> 
cot> 
WW 


Ph" 

Ph o 

CO'hfl 
<3 CD 

3p^ 


co 

c3 
H 

o 
o 

s 


co 

CD 

o 
o 

Hi 


co • 

d <u 

flo 
W 




<1 


PhQ 


g-B 


o 




Q 


PhC 


p 03 


Ph 




W 


>hH 


g<3 


W 


H 


<1 






O 


O 


w 


ffl 


Hi 



(180) 



=* 


iO 


o 


« 


CO 


F» 1 I>= 


eo 


r-=« 


1 


^ 


t>- 


"<* 


■* 


CD 


»o 


t» 


t>. 


O 


CN 


CN 


CN 


CN 


CD 


00 


00 


00 


CO 


»o 


ID 


CO 


CO 


CO 


CO 


CN 


1> 


In. 


l>. 


tO 


iO 


00 


00 


CO 


1< 


1* 


-* 


CO 


00 


OS 


OS 


CO 


o 


"* 


TP 


00 


CO 


CO 


CO 


^ 




•**eocN 


OS OS t^- CO 


csost>co 


tN 


t^COCN 


CTN N 00 


CNCNCN00 


CN 


t-l>I> 


0000 00 t> 


00 00 00 1> 


CO 


rflOSOO 


COO CD CO 


COOCOCD 


CNOO 


HIO© 


t>C0 00 t-- 


r^cocot^ 


CNi-iOO 


OiO0t> 


OO OS 00 


0003 00 


00 00 b- 




r-l I—l 


l-H l-H 




eocot>. 


iCOO 00 iO 


lOOOOOlO 


COOOUO 


OCNr+l 


»o«o 00 CO 


lOiOOOCO 


O"*00 


OOSGO 


CNi-h O OS 


(Ni-HOOS 


OOSOO 


i—l 


i-li-H i-l 


i-H I-H rH 


I—l 


tO CD CO 


OiO 00 o 


OiOOOO 


OHN 


iOCOI> 


coco •<# i> 


CDC0TtH> 


l-H CO T* 


OO3 00 


CO CM rH OS 


CO CN i-H OS 


r-i O OS 


i— 1 


i—l I-H I-H 


l-H l-H i-H 


l-H l-H 


OOO 


OO o o 


OOOO 


ooo 


ooo 


■OO o o 


lOOOO 


ooo 


HO» 


-*CO tN O 


"tf C0CNO 


WHO 


I—l l-H 


I— I i-H i-H i-H 


l— 1 l-H l-H l-H 


rH i-H i-H 


P 


1 

w 

£5o2f« 




^£ 


QTHERN PI 
3PECTI0N E 

U OF THE 

N PINE ASS 


LIFORNIA 

DWOOD 

30CIATI0N 


TIONAL 

RDWOOD 

30CIATI0 


22 03 


o>z<n 


<1Hco 


fcH<! 


OPh<1 


CO 




T3 


t3 


■43 






CD 


.r-l 3 3 
rfl 

03 3 

OOO 


t Structural 
e Structural 
ih'ble Structura 
Sq. Edge & Snd 
Structural 


Select Strl. 
Structural 
Strl. Sq. E. & 
No. 1 Strl. 


C Clse. Grain 
C " 

C " " 


4J:** 


CO Ct> CO CO 


=£1= =♦}; =tt: 


ooo 
ooo 


o> a £— i 

r-'H 0) h O 


CO <n CO to 

q c a d 

0} 02 G2 


OOO 
OOO 


l-HOOS 

rH I—l 


ID -f< *H -t» yZ 


PPQP 


CNi-hO 
rH rH rH 








T3 








CO 








a 








o3 - a 








o 


OOO 






CO 


=fc%=fc 


OOOOO 


OOOO 


o 


OOO 

ooo 


^ ^ ^ ^t ^ 


^i =rt: =fc): 4t; 


ooo 


i-hOOS 


OOOOO 


OOOO 


^^^ 


I—l T-t 


lOOOOO 


«oooo 




TfCCNNO 


"#COCNO 


ooo 




i-H i-H rH i-H 


rH i-H rH rH 


ooo 

(MHO 




CO 

m 

®^3 5 


CO 

co 

CD c3 ,_, 


P 

O 


«£ 


Q co CO 

.•as 

H«3 




o 




H03 


Q 
H 


£ o o 


5j o 


o 


Ph 


Ph 


P3 



(181) 



PART 26. 

REINFORCED CONCRETE, 

Section 

2601 — Design of Reinforced Concrete. 

2602 — Definitions Pertaining to Reinforced Concrete. 

2603 — Inspection of Concrete. 

2604 — Tests of Materials of Reinforced Concrete. 

2605 — Cement. 

2606 — Concrete Aggregates. 

2607 — Water in Concrete. 

2608 — Metal Reinforcement. 

2609 — Storage of Materials for Concrete. 

2610 — Concrete Quality. 

261 1 — Average Concrete. 

2612 — Controlled Concrete. 

2613 — Field Tests of Concrete. 

2614 — Concrete Proportions and Consistencies. 

2615 — Mixing Concrete. 

2616 — Concrete Forms and Equipment. 

2617 — Removal of Water from Excavations, 

2618 — Transporting Concrete. 

2619 — Placing Concrete. 

2620 — Depositing Concrete in Cold Weather. 

2621 — Curing Concrete. 

2622 — Construction Joints in Concrete. 

2623 — Bonding Fresh and Hardened Concrete. 

2624 — Bending Reinforcement. 

2625 — Placing Reinforcement. 

2626 — Splices in Reinforcement. 

2627 — Protective Covering of Reinforcement. 

2628 — Pipes and Conduits Embedded in Concrete. 

2629 — Allowable Unit Stresses in Concrete. 

2630 — Allowable Unit Stresses in Steel. 

2631 — Design of Reinforced Concrete for Wind Loads. 

2632 — Design of Reinforced Concrete in Flexure. 

(182) 



Section 

2633 — Span Length of Reinforced Concrete Members. 

2634 — Depth of Reinforced Concrete Beams or Slabs. 

2635 — Analysis of Bending in Reinforced Concrete. 

2636 — Arbitrary Moment Coefficients for Reinforced Concrete. 

2637 — Points of Inflection in Reinforced Concrete, and Shear. 

2638 — Diagonal Tension in Reinforced Concrete Beams. 

2639 — Types of Web Reinforcement. 

2640 — Design of Web Reinforcement. 

2641 — Shearing Stress in Concrete Flat Slabs. 

2642 — Shear and Diagonal Tension in Footings. 

2643 — Bond Stress in Reinforced Concrete. 

2644 — Ordinary Anchorage of Reinforcement. 

2645 — Special Anchorage of Reinforcement. 

2646 — Anchorage of Web Reinforcement. 

2647 — Slenderness of Reinforced Concrete Beams. 

2648 — T=Beams of Reinforced Concrete. 

2649 — Compression Reinforcement in Beams and Girders. 

2650 — Structural Steel Beams Encased in Concrete. 

2651 — Shrinkage and Temperature Reinforcement. 

2652 — Concentrated Loads on Concrete Slabs. 

2653 — Concrete Ribbed and Combination Slabs. 

2654 — Two=way Slabs of Reinforced Concrete. 

2655 — Limitations upon Reinforced Concrete Flat Slabs. 

2656 — Assumptions in Concrete Flat Slab Design. 

2657 — Bending in Interior Flat Slab Panels. 

2658 — Spacing of Flat Slab Reinforcement. 

2659 — Thickness of Concrete Flat Slabs. 

2660 — Point of Inflection in Flat Slabs. 

2661 — Arrangement of Flat Slab Reinforcement at Column Heads. 

2662 — Arrangement of Flat Slab Reinforcement — Two=way System. 

2663 — Arrangement of Flat Slab Reinforcement — Four=way System. 

2664 — Flat Slab Reinforcement Other than Two=way or Four=\vay. 

2665 — Discontinuous Flat Slab Panels. 

2666 — Marginal Beams in Flat Slabs. 

2667 — Openings in Flat Slabs. 

2668 — Construction Joints in Flat Slabs. 

2669 — Limiting Dimensions of Concrete Columns. 

2670 — Unsupported Length of Concrete Columns. 

(183) 



Sees. 2601=2602 

2671 — Design of Spirally Reinforced Concrete Columns. 

2672 — Design of Tied Reinforced Concrete Columns. 

2673 — Long Columns. 

2674 — Bending in Concrete Columns. 

2675 — Combined Axial and Bending Stresses. 

2676 — Allowable Combined Axial and Bending Stresses, 

2677 — Combination Columns. 

2678 — Concrete Walls. 

2679 — Sloped or Stepped Concrete Footings. 

2680 — Bending in Concrete Footings. 

2681 — Plain Concrete Footings. 

2682 — Bearing on Concrete Footings. 

2683 — Pedestals — Plain Concrete. 

Section 2601. Design of Reinforced Concrete. — Reinforced concrete 
shall be designed by methods admitting of rational analysis according to 
established principles of mechanics, supplemented by the assumptions herein 
specified, to support the loads and withstand the forces to which it is subject 
without exceeding the stresses allowed in this part for the various materials 
thereof. 

*Sect. 2602. Definitions Pertaining to Reinforced Concrete. — (a) 

The following terms are defined for use in this part of the code: — 

Aggregate: Inert material used as a filler in concrete. 

Blast-Furnace Slag: The non-metallic product, consisting essential^ of 
silicates and alumino-silicates of lime, which is developed simultaneously with 
iron in a blast furnace. 

Column: An upright compression member the length of which exceeds 
three times its least lateral dimension, excluding piles and caisson piers. 

Column Capital : An enlargement of the upper end of a reinforced concrete 
column designed and built to act as a unit with the column and flat slab. A 
framework of metal for the same purpose. 

Column Strip : A portion of a flat slab panel one half panel in width occupy- 
ing the two quarter-panel areas outside of the middle strip. (See Middle 
Strip.) 

Combination Column: A column in which a structural steel section, de- 
signed to carry the principal part of the load, is encased in concrete in such 
a manner that some additional load may be allowed. 

Composite Column: A column in which the structural steel or cast iron 
column designed to carry the principal part of the load is encased in concrete 
containing reinforcement of spiral and longitudinal steel. 

Concrete: A mixture of Portland cement, fine aggregate, coarse aggregate 
and water. 

(184) 



Sec. 2602 

Diameter: The diameter of a square bar shall be the distance between 
opposite sides. The diameter of a deformed bar shall be the diameter of a 
plain bar having the same area of cross-section. 

Dropped Panel: The structural portion of a flat slab which is thickened 
throughout an area surrounding the column capital. 

Effective Area of Concrete: Of a cross-section, the area which lies between 
the centroid of the tensile reinforcement and the compression surface in a 
beam or slab, and having, a width equal to the width of the rectangular beam 
or slab, or the effective width of the flange of a T-beam. 

Effective Area of Reinforcement: The area obtained by multiplying the 
right cross-sectional area of the metal reinforcement by the cosine of the angle 
between its direction and that for which the effectiveness of the reinforcement- 
is to be determined. 

Flat Slab: A concrete slab reinforced in two or more directions generally 
without beams or girders to transfer the loads to columns. 

Hook: A hook made by bending a length at the end of a bar one hundred 
and eighty degrees about a pin of a diameter not less than five nor more than 
eleven bar-diameters, with a straight extension of at least four bar-diameters 
at the free end. 

Laitance: Extremely fine material of little or no strength which may collect 
on the surface of freshly deposited concrete or mortar, usually recognized by 
its relatively light color. 

Middle Strip: A portion of a flat slab panel one half panel in width, sym- 
metrical with respect to the panel center line and extending through the panel 
in the direction in which bending moments are being considered. 

Paneled Ceiling: The ceiling of a flat slab in which approximately that 
portion of the area enclosed within the intersection of the two middle strips is 
reduced in thickness. 

Panel Length: In a flat slab, the distance along a panel side from center to 
center of columns. 

Pedestal: An upright compression member whose height does not exceed 
three times its least lateral dimension. 

Pedestal Footing: A column footing projecting less than one half its depth 
from the faces of the column on all sides and having a depth not more than 
three times its least width. 

Portland Cement: The product obtained by finely pulverizing clinker pro- 
duced by calcining to incipient fusion an intimate and properly proportioned 
mixture of argillaceous and calcareous materials, with no additions subse- 
quent to calcination excepting water and calcined or uncalcined gypsum. 

Ratio of Reinforcement: The ratio of the effective area of the reinforce- 
ment cut by a section of a beam or slab to the effective area of the concrete 
at that section. 

Reinforced Concrete: Concrete in which metal other than that provided 
for expansion and contraction, is embedded in such a manner that the two 
materials act together in resisting forces. 

(185) 



Sec. 2602 

Screen: A metal plate with closely spaced circular perforations. 
Sieve: Woven wire cloth or a metal plate with square openings of uniform 
size. 

Strut: A compression member other than a column or pedestal. 

Water-Cement Ratio: The total quantity of water entering the concrete 
mixture, including the surface water carried by the aggregate, expressed in 
terms of the quantity of cement. The water-cement ratio shall be expressed 
in U. S. gallons per bag (ninety-four pounds) of cement. 

(b) The symbols and notations used in this part are defined as follows: 

a — Angle between inclined web bars and axis of beam. 

A — Total area of pedestal, pier, or footing at the column base. 

A' — Loaded area of pedestal, pier, or footing at the column base. 

A c — Total area of the concrete section = A g -A r . 

A r — The ei oss-sectional area of the steel column. 

A g — Gross area of concrete column. 

A 8 — Effective cross-sectional area of steel in tension in beams and slabs, or 

compression in columns. 
A v — Total area of cross-section of one unit of web reinforcement. 
b — Width of rectangular beam or width including flange of T-beam. 
b' — Thickness of web in beams of I or T section. 
c- — Diameter of column capital of a flat slab. 

c' — The distance from gravity axis to extreme fiber in compression. 
C — The ratio of f a to the allowable fiber stress for members in flexure. 
Co — In two-way slab design, coefficient dependent on position of panel 

relative to adjacent continuous panels. 
Ci — Coefficient for bending dependent upon continuity and restraint. 
d — Depth of beam or slab from compression face to center of longitudinal 

tensile reinforcement, 
d' — Least lateral dimension of a column. 

e — The eccentricity of resultant load, measured from the gravity axis. 
E c — Modulus of elasticity of concrete in compression. 

E 8 — Modulus of elasticity of steel (thirty million pounds per square inch). 
f a — Average allowable stress on an equivalent axially loaded concrete 

column. 
f c — Compressive unit stress in concrete. 

f' c — Ultimate compressive strength of concrete at age of twenty-eight days. 
f' r — The allowable stress for unencased steel column. 
f B — Tensile unit stress in longitudinal reinforcement. 

f' 8 — The useful limit stress of spiral reinforcement. See Sec. 2671, par. (d). 
f v — Tensile unit stress in web reinforcement, 
g — Sum of perimeters of bars in one set. 

(186) 



Sees. 2602=2603 

h — Unsupported length of column. 

I — Moment of inertia of a section about the neutral axis for bending. 

j — Ratio of arm of resisting couple in bending to depth (d). 

L — Span length of beam or slab; length or width of flat slab panel. 

Li — Length of width of a two-way or flat slab panel at right angles to the 
direction in which bending is considered. 

M — Bending moment or moment of resistance in general. 

M — Sum of positive and negative bending moments at the principal design 

sections of a panel of a flat slab. 
n — Ratio of modulus of elasticity of steel to that of concrete (E 8 /E c ). 
p — Ratio of effective area of tensile reinforcement in bending. 

p' — Ratio of volume of spiral reinforcement to the volume of the concrete 
core (out to out of spirals). 

p g — Ratio of the effective cross-sectional area of vertical reinforcement 

to the gross area A g . 
P — Total safe axial load on a short column. 
P' — Total safe axial load on a long column. 
r — Ratio of breadth to span of panel of a two-way slab. 

R — Least radius of g}Tation of a column section or equivalent concrete 
section. 

s — Spacing of web reinforcement measured along the axis of the beam. 

s' — Distance from the center of a concentrated load to nearer support of a 

slab, 
t — Thickness of flange of T-beams. 
t' — The overall depth of section. 

ti — Thickness of flat slab near column (including dropped panel, if any). 
t2 — Thickness of flat slab outside the dropped panel, 
u — Bond stress per unit of surface area of bar. 
v — Shearing unit stress. 
V — Total shear at a cross -section. 

V — Excess of the total shear over the allowed resistance in shear of the 

concrete unreinforced. 
w — Uniformly distributed load per unit length of beam or slab or per unit 

area. 

w' — Actual width of a concentrated load upon a slab. 
W — Total uniformly distributed load in a single panel area. 
[ *As amended by Ord. 1943, ch. 8 ] 

Sect. 2603. Inspection of Concrete. — The commissioner shall require 
an applicant for a permit involving the structural use of concrete to have a 
competent inspector at all times on the work while such concrete is being 
proportioned, mixed and deposited. 

(187) 



Sees. 2604=2607 

Sect. 2604. Tests of Materials of Reinforced Concrete. — The 

commissioner shall have the right to require reasonable tests from time to 
time to determine whether the materials and methods in use are such as to 
produce reinforced concrete of the necessary quality. Copies of the reports 
of such tests shall be kept readily available by the commissioner for a period 
of two years after the completion of the structure. 

Sect. 2605. Cement. — (a) Portland cement shall conform to the 
Standard Specifications and Tests for Portland Cement of the American 
Society for Testing Materials. 

(b) Special cement may be used for Portland cement, subject to the ap- 
proval of the commissioner, provided it meets the requirements for Portland 
cement in regard to strength, soundness and setting time. 

Sect. 2606. Concrete Aggregates. — (a) Concrete aggregates shall 
consist of graded natural sands and gravels, crushed rock, or other inert 
materials having clean, uncoated grains of strong and durable minerals. 
Aggregates containing soft, friable, thin, flaky, elongated or laminated par- 
ticles totaling more than three per cent, or containing shale in excess of 
one and one half per cent, or silt and crusher dust finer than the number 
one hundred standard sieve in excess of two per cent, shall not be used. 
These percentages shall be based on the weight of the combined aggregate 
as used in the concrete. When all three groups of these deleterious materials 
are present in the aggregates, the combined amounts shall not exceed five 
per cent by weight of the combined aggregate. 

(b) Burnt shale or clay, cinders, slag or other hard, clean, inert, artificial 
materials may be used as concrete aggregates, subject to the approval of the 
commissioner, provided they contain not more than one per cent by weight 
of sulphur or similar compounds (free or combined), nor more than ten per 
cent by weight of combustible matter, are properly prepared by crushing and 
screening to give a graded coarse and fine aggregate, and come from a source 
that is known to give uniform quality. 

(c) Fine aggregate shall not contain organic material sufficient to give 
a color darker than the standard color when tested in accordance with the 
Standard Method of Test for Organic Impurities in Sands for Concrete of 
the American Society for Testing Materials. 

(d) Coarse aggregate shall not be larger than one fifth of the narrowest 
dimension between forms of the member in which the concrete is to be used, 
nor larger than three fourths of the minimum clear spacing between reinforcing 
bars. By maximum size of aggregate is meant the smallest sieve size through 
which eighty-five per cent by weight of the materials can be passed. Aggre- 
gate larger than one inch of sandstone, granite, quartzite and siliceous gravel 
shall not be used in fire-protective concrete. 

(e) Fine aggregate shall consist of all particles passing a number four sieve. 

Sect. 2607. Water in Concrete. — Water used in mixing concrete shall 
be free from injurious amounts of acids, salts, alkalies or organic materials. 

(188) 



Sees. 2608=2610 

Sect. 2608. Metal Reinforcement. — (a) Metal reinforcement shall 
be steel bars conforming to the requirements of the Standard Specifications 
for Billet-Steel Concrete Reinforcement Bars of Structural or Intermediate 
Grade, or for Rail-Steel Concrete Reinforcement Bars of the American 
Society for Testing Materials, or rerolled bars, whether from rails or from 
other suitable approved sections, which otherwise meet the requirements of 
one of the three specifications, or wire or expanded metal. The provision in 
these specifications for machining deformed bars before testing shall be 
disregarded. The tests called for in the said specifications shall always be 
made when rerolled steel is used. 

(b) Wire for concrete reinforcement shall conform to the requirements 
of the Specifications for Cold-Drawn Steel Wire for Concrete Reinforcement 
of the American Society for Testing Materials. 

(c) Structural steel shall conform to the requirements of Part 28. 

(d) Cast-iron sections for composite columns shall conform to the require- 
ments of Part 28. 

(e) Deformed bars shall have closely spaced shoulders, lugs or projections 
formed integrally in rolling, of such nature as to produce a bond or resistance 
to slipping when embedded in concrete, at least twenty-five per cent greater 
than that of plain hot-rolled round bars. Wire mesh with welded intersections 
not further apart than twelve inches (six inches in web reinforcement) in the 
direction of the principal reinforcing, and with cross wires of at least number 
ten gage, or expanded metal, may be rated for bond as deformed bars. 

Sect. 2609. Storage of Materials for Concrete. — Cement and aggre- 
gates shall be stored at the work in a manner to prevent deterioration or the 
intrusion of foreign matter. Any material which has deteriorated or has 
been damaged shall not be used in concrete. 

Sect. 2610. Concrete Quality. — (a) The allowable unit stresses for 
the design of reinforced concrete structures shall be based upon the twenty- 
eight-day strength of the concrete to be used in the structure in accordance 
with the values given in section twenty-six hundred and twenty-nine. Plans 
submitted for approval or used on the work shall clearly show the strength 
of concrete for which all parts of the structure were designed. The strength 
of concrete shall be determined in accordance with one of the following 
methods: — 

(1) By established results for average materials as provided in section 
twenty-six hundred and eleven (Average Concrete). 

(2) By specific test of materials for the structure as provided in section 
twenty-six hundred and twelve (Controlled Concrete). 

(b) Structural concrete made with artificial aggregates, with special 
cements, or with admixtures, shall always be made in accordance with 
method (2) for controlled concrete. (The water-cement ratio strength 
relation will generally be different than for natural aggregates, normal 
cement, or usual mixtures.) The commissioner may waive the requirements 
of this paragraph subject to such conditions as he may specify. 

(189) 



Sees. 2611=2612 

Sect. 2611. Average Concrete. — (a) The following table gives the 
compressive strength in pounds per square inch which shall be assumed as 
the basis for design where no preliminary concrete strength tests of the 
materials to be used are made. A bag of cement weighing ninety-four pounds 
shall be assumed to measure one cubic foot. 

Assumed Strengths of Concrete Mixtures. 



Minimum Proportions: 

Volume of Portland Cement to 

Sum of Separate Volumes of 

Fine and Coarse Aggregates, 

measured Dry and Loose. 


Maximum Water-Cement 

Ratio, United States 

Gallons per Bag of 

Cement, i 


Assumed Compressive 

Strength at 28 Days 

(Pounds per Square Inch). 


1:7M 

1:6 

1:5 

1:4 

1:3 


8.00 
7.25 
6.50 
6.00 
5.00 


1,500 
2,000 
2,500 
3,000 
3,750 



1 Including the water content of the aggregate. Unless this content is determined by 
tests, it shall be assumed to be one half gallon per cubic foot of fine aggregate. 

(b) During the progress of the work, such reasonable number of com- 
pression tests shall be made as may be required by the commissioner, but 
at least one set of specimens shall be tested for each three hundred cubic 
yards of each different mixture of concrete being placed. The tests shall 
be made in accordance with provisions of section twenty-six hundred and 
thirteen. If the average twenty-eight-day strength falls below the strength 
called for on the plans, the commissioner shall have the right to require a 
load test under the provisions of Part 23. The commissioner may waive 
the requirement of tests on work involving in all less than two hundred cubic 
yards of concrete. 

(c) Average concrete exposed to the weather shall contain not less than 
six bags of cement per cubic yard of concrete and the water-cement ratio 
shall not exceed six gallons per bag of cement. 

Sect. 2612. Controlled Concrete. — (a) When the proportions are to 
be established by tests, the tests shall be made in advance of the beginning 
of construction using the materials proposed and consistencies suitable for 
the work and in accordance with the provisions of section twenty-six hundred 
and thirteen. The relation between the average twenty-eight-day strength 
of the concrete and the water-cement ratio shall be determined by such 
tests for a range of values including all of the strengths called for on the 
plans. The water-cement ratio determined for each quality of concrete to 
be used shall allow sufficient margin of strength to provide for the exigencies 
of field operations. In no case, however, shall concrete exposed to the 
weather contain less than five bags of cement per cubic yard of concrete or 
have a water-cement ratio in excess of six gallons per bag. No change or 
substitution shall be made in the materials being used on the work without 
additional tests to determine the new water-cement ratios to be used. 

(190) 



Sees. 2612=2614 

(b) During the progress of the work, a reasonable number of compression 
tests may be required by the commissioner, but at least one set of specimens 
shall be tested for each one hundred and fifty cubic yards of concrete of a 
given strength, and not less than one set of specimens of each strength of 
concrete for each day's operation. Such tests shall be made in accordance 
with the provisions of section twenty-six hundred and thirteen. If the 
average twenty-eight-day strength of the tested specimens for any portion 
of the structure falls below the strength called for on the plans, the com- 
missioner shall have the right to require load tests as specified in Part 23 on 
the portions of the building affected, and to order a change in the mixture 
for the remaining portion of the structure. 

(c) Controlled concrete shall be proportioned, mixed and placed under 
the supervision of an approved concrete control engineer. 

Sect. 2613. Field Tests of Concrete.— (a) Specimens for compres- 
sion tests of concrete, when required, shall be made and stored in accordance 
with the Standard Method of Making and Storing Compression Test Speci- 
mens of Concrete in the Field, and tested in accordance with the Standard 
Method of Making Compression Tests of Concrete, of the American Society 
for Testing Materials; provided, that each set shall consist of at least three 
specimens which shall be stored under moist curing conditions at seventy 
degrees Fahrenheit, and no specimens need be stored on the structure. 

(b) If tests disclose a consistent relation between the seven-day and the 
twenty-eight-day strength of the concrete, the tests required during the 
progress of concrete work may be made at seven days and the strength at 
twenty-eight days determined therefrom. 

Sect. 2614. Concrete Proportions and Consistencies. — (a) The 

proportions of cement and aggregates for concrete shall be such as to produce 
concrete that will work readily into the corners and angles of the forms and 
around the reinforcement without excessive puddling or spading and without 
permitting the materials to segregate or free water to collect on the surface. 
The combined aggregate shall be of such composition of sizes that when sepa- 
rated by a number four standard sieve, the weight retained on the sieve shall 
not be less than one third nor more than two thirds of the total. The consist- 
ency of the concrete shall be such that the slump as measured by the slump 
test shall not exceed the values given in the following table: — 



CLASS OF CONCRETE. 


Maximum Allowable Slump. 


Heavy foundations, massive walls 


4 inches 




6 inches 







(b) The methods of measuring concrete materials shall be such that the 
proportion of all ingredients including water can be accurately controlled 
during the progress of the work and easily checked at any time by the 
commissioner. 

(191) 



Sees. 2615=2620 

Sect. 2615. Mixing Concrete. — Concrete shall be mixed until there is a 
uniform distribution of the materials and the mass is homogeneous and 
uniform in color. In machine mixing, only batch mixers shall be used. 
Each batch shall be mixed not less than one minute after all the materials 
are in the mixer and must be completely discharged before the mixer is 
recharged. 

Sect. 2616. Concrete Forms and Equipment. — (a) Forms shall be 
substantial and sufficiently tight to prevent loss of mortar from the concrete. 

(b) Before concrete is placed equipment for mixing and transporting the 
concrete and forms shall be clean; the spaces to be occupied by the concrete 
shall be free of snow, ice and debris. 

Sect. 2617. Removal of Water from Excavations. — Water shall be 
removed from excavations before concrete is deposited, unless otherwise 
directed by the commissioner. Water flowing into an excavation shall be 
diverted through proper side drains to a sump, or be removed by other ap- 
proved methods which will avoid washing the freshly deposited concrete. 

Sect. 2618. Transporting Concrete. — (a) Concrete shall be handled 
from the mixer to the place of final deposit by methods which will prevent the 
separation or loss of the ingredients. Under no circumstances shall concrete 
that is partially hardened be deposited in the work. 

(b) Concrete otherwise meeting the requirements of this code but mixed 
at a distance from the structure in which it is to be deposited may be used pro- 
vided the time elapsed between addition of the cement to the aggregate and its 
deposit in the forms does not exceed one hour. 

Sect. 2619. Placing Concrete. — (a) Concrete shall not be placed until 
the forms and reinforcement have been inspected and approved by the in- 
spector required by section twenty-six hundred and three. 

(b) When concreting is once started, it shall be carried on as a continuous 
operation until the placing of the section or panel is completed. The top 
surface shall be kept generally level and accumulations of water on the surface 
shall be promptly removed. Where construction joints are necessary, they 
shall be made in accordance with section twenty-six hundred and twenty-two. 

(c) Concrete shall be thoroughly compacted by puddling with suitable 
tools during the operation of placing, and thoroughly worked around the 
reinforcement. 

Sect. 2620. Depositing Concrete in Cold Weather. — When deposit- 
ing concrete at freezing or near freezing temperature, the concrete shall be 
maintained at a temperature of not less than fifty degrees Fahrenheit, and not 
more than one hundred and twenty degrees. The temperature of the concrete 
shall be maintained at not less than fifty degrees for at least seventy-two hours 
after placing. When necessary, concrete materials shall be heated before 
mixing. Dependence shall not be placed on salt or other chemicals for the 
prevention of freezing. 

(192) 



Sees. 2621=2625 

Sect. 2621. Curing Concrete. — (a) Exposed surfaces of concrete shall 
be kept moist for a period of at least seven days after being deposited. 

(b) Forms shall be removed in such a manner and with such precautions 
as to insure complete safety of the structure. 

*Sect. 2622. Construction Joints in Concrete. — (a) Joints not 
indicated on the plans shall be so made and located as least to impair the 
strength of the structure. Such joints in floors shall be located near the 
middle of spans of slabs, beams, or girders, unless a beam intersects a girder 
at this point, in which case the joint in the girder shall be offset a distance 
equal to twice the width of the beam. At least two hours must elapse after 
depositing concrete in columns or walls before depositing in beams, girders, or 
slabs supported thereon. Beams, girders, brackets, column capitals, and 
haunches shall be considered part of the floor system and shall be placed 
monolithically therewith. All joints shall be bonded in accordance with sec- 
tion twenty-six hundred and twenty-three. (For construction joints in flat 
slabs, see also section twenty-six hundred and sixty-eight.) 

(b) Construction joints shall occur within the middle third of the span 
and preferably where the shear is least. At each such joint, reinforcing steel 
shall be provided perpendicular to the joint and near the top of the slab and 
its amount shall be equal to .003 of cross-section area of the concrete. These 
rods shall be spaced not over two times the thickness of the slab or within 
the width of the beam or girder. Rods shall be fully anchored each side of the 

joint. 

[ *As amended by Ord. 1943, ch. 8 and Ord. 1955, ch. 2.} 

fSect. 2623. Bonding Fresh and Hardened Concrete. — Before new 
concrete is deposited on or against concrete which has set, the surface of the 
set concrete shall be roughened, cleaned of foreign matter and laitance and 
thoroughly wetted but not saturated. Such surfaces shall first be slushed 
with a coating of neat cement grout, against which, before it has attained its 
initial set, the new concrete shall be placed. 

[ \As amended by Ord. 1943, ch. 8 ] 

Sect. 2624. Bending Reinforcement. — Metal reinforcement shall not 
be bent, straightened or handled in any manner that will injure the material. 
Reinforcement may be heated only when approved by the commissioner. 
Cold bends shall be made around a pin having a diameter of not less than 
four times the diameter of the bar. Bars with kinks or bends not shown on 
the plans shall not be used. 

Sect. 2625. Placing Reinforcement. — (a) Metal reinforcement shall 
be clean and free of loose mill and rust scale and of other coatings that would 
destroy or reduce the bond. It shall be accurately placed, supported and 
secured. 

(b) The minimum clear distance between parallel bars shall be one and 
one half times the diameter for round bars and twice the diameter for square 
bars. If the ends of bars are anchored as specified in section twenty-six 
hundred and forty-five, the clear spacing may be made equal to the diameter 

(193) 



Sees. 2625=2628 

of round bars or to one and one half times the diameter of square bars, but 
in no case shall the spacing between bars be less than one inch, nor less than 
one and one third times the maximum size of the coarse aggregate. The 
minimum clear distance between bars and forms shall be the diameter of 
round bars and one and one half times the diameter of square bars. Bars 
shall be embedded a distance from the face of a member not less than the 
distance required for fire and rust protection in this code. The main longi- 
tudinal steel of a reinforced concrete slab shall be spaced not more than three 
times the slab thickness. 

Sect. 2626. Splices in Reinforcement. — (a) In slabs, beams and 
girders, splices of reinforcement shall generally be avoided at points of maxi- 
mum stress and, where made, shall provide sufficient lap to transfer the stress 
by bond and shear. 

(b) In columns longitudinal reinforcement may be spliced by lapping 
the bars a length sufficient to develop the working stress in the reinforcement 
by means of bond, but in no case shall the lap be less than twenty-four bar 
diameters for deformed bars or thirty diameters for plain bars. Butt joints of 
approved design are permitted at points where only compressive stress occurs. 

Sect. 2627. Protective Covering of Reinforcement. — (a) At the 

underside of footings and elsewhere in concrete poured in contact with the 
ground, the main metal reinforcement shall have a minimum covering of 
three inches except that in floor slabs poured on dry earth such covering 
may be one and one half inches. In concrete poured in forms but exposed 
to soil backfill, moisture or weather, such covering shall be two inches. 

(b) In buildings of Type I and Type II construction, and in other rein- 
forced concrete required to have specified fire resistance, main metal rein- 
forcement shall be protected as required in sections one hundred and twenty- 
four to one hundred and thirty-one, inclusive, of Part 1, in Parts 16, 17 and 
22, respectively, and elsewhere in this code. 

(c) Bars used for the support or spacing of reinforcement, shrinkage 
reinforcement, column ties and stirrups not over one half inch in diameter, 
shall not be considered main reinforcement. Such bars shall have minimum 
protective covering one half inch less than specified in this section for main 
reinforcement. 

Sect. 2628. Pipes and Conduits Embedded in Concrete. — Pipes 
which will contain liquid, gas or vapor at other than room temperature shall 
not be embedded in concrete necessary for structural stability or fire pro- 
tection. Drain pipes and pipes whose contents will be under pressure greater 
than atmospheric pressure by more than one pound per square inch shall not 
be embedded in structural concrete except in passing through from one side 
to the other of a floor, wall or beam. Electric conduits and other pipes 
embedment of which is allowed shall not, with their fittings, displace that 
concrete of a column on which stress is calculated or which is required for 
fire protection, to greater extent than four per cent of the area of cross-section. 
Sleeves or other pipes passing through floors, walls or beams shall not be of 

(194) 



Sects. 2628=2629 

such size or in such location as unduly to impair the strength of the construc- 
tion; such sleeves or pipes may be considered as replacing structurally the dis- 
placed concrete, provided they are not exposed to rusting or other deterioration, 
are of galvanized or uncoated iron or steel not thinner than standard wrought 
iron pipe, have a nominal inside diameter not over two inches, and are spaced 
not less than three diameters on centers. Embedded pipes or conduits other 
than those merely passing through shall not be larger in outside diameter than 
one third the thickness of the slab, wall or beam in which they are embedded, 
shall not be spaced closer than three diameters on centers, nor so located as 
unduly to impair the strength of the construction. Circular uncoated or 
galvanized electric conduit of iron or steel may be considered as replacing the 
displaced concrete. 

*Sect. 2629. Allowable Unit Stresses in Concrete. — (a) Rein- 
forced concrete members shall be designed with reference to safe loads and 
working stresses. The unit stresses in pounds per square inch in concrete of 
the strength indicated shall not exceed the following allowable values, where 
(f' c ) is the strength at twenty-eight days: — 





Allowable Unit Stresses. 




Expressed 

as a 
Proportion 

of the 
Strength. 


Specific Values for 

Common Strengths 

(Pounds per Square Inch). 






Strength. 






2,000. 


2,500. 


3,000. 


Flexure: 


0.40 f'c 

0.02 f'c 

0.03 f'c 

0.06 f'c 

0.09 f'c 

0.025 f'c 
0.02 f'c 

0.04 f'c 
0.05 f'c 

0.25 f'c 
0.375 f'c 

0.18 f'c 

0.225 f'c 


n = 15 


n = 12 


n = 10 


Extreme fiber stress in compression 


800 

40 

60 

120 

180 

50 
40 

80 
100 

500 
750 

360 

450 


1,000 

50 

75 

150 

225 

62 
50 

100 
125 

625 
937 

450 

562 


1,200 


Shear: 

Beams with no web reinforcement and without 

Beams with no web reinforcement, but with spe- 


60 
90 


Beams with web reinforcement, but without spe- 


180 


Beams with web reinforcement and with special 


270 


Flat slabs at distance (d) from edge of column 


75 
60 


Bond: 

Plain bars not to exceed 160 # O" 


120 


Bearing: 


150 
750 


Axial Compression: 


1,125 
540 


In columns with continuous spirals enclosing a 


675 







(b) The bond stress computed in accordance with section twenty-six 
hundred and forty-three may be allowed to reach double these values where 
special anchorage is provided as specified in section twenty-six hundred 
and forty-five. 

(c) The allowed bearing stress on an area greater than one third but less 
than the full area shall be interpolated between the values given in the table. 

(195) 



Sees. 2629=2632 

(d) The ratio of the moduli of elasticity of steel and concrete shall be 

30,000. 
assumed as (n) = ■ 

1 c 

[ *As amended by Ord. 1948, ch. 8 ] 

fSect. 2630. Allowable Unit Stresses in Steel. — (a) The following 
allowable unit stresses shall not be exceeded in reinforcing steel. 

Allowable Unit Stress (Pounds per Square Inch). 

Tension : 

Structural grade billet steel bars 18,000 

Rerolled steel bars 18,000 

Intermediate grade billet steel bars 20,000 

Cold drawn steel wire or cold stretched expanded metal fabric 20,000 

Rerolled rail steel reinforcing bars 20,000 

Web reinforcement (steel) 16,000 

Other steel reinforcement fifty per cent of the yield point, but 

not to exceed 18,000 

(b) Compression in reinforcing steel except in columns, shall not exceed 
(n) times the compressive stress in the concrete at a line in the cross-section 
through the center of the bars. 

(c) Compression in structural steel and cast iron in composite and com- 
bination columns shall not exceed the stress specified in sections twenty-six 
hundred and seventy-five and twenty-six hundred and seventy-six. 

(d) The modulus of elasticity shall be assumed as thirty million pounds 
per square inch. 

[ 1[As amended by Ord. 1943, ch. 8 and Ord. 1949, ch. 8 ] 

Sect. 2631. Design of Reinforced Concrete for Wind Loads. — In 

designing the members of reinforced concrete structures to resist wind loads, 
the allowable unit stresses for dead and live load and wind loads may be 
increased to four thirds of the allowable values specified in sections twenty-six 
hundred and twenty-nine and twenty-six hundred and thirty, but no member 
shall be less than that required if the wind load be neglected. 

Sect. 2632. Design of Reinforced Concrete in Flexure. — (a) The 

accepted theory of flexure as applied to reinforced concrete shall be applied 
to all members resisting bending. The following assumptions shall be made : — ■ 

(1) The steel alone resists tensile stress and acts only in the direction 
of its length. 

(2) The ratio (n) of the modulus of elasticity of the steel either in 
tension or compression to that of any given concrete is constant. 

(3) Plane sections before bending remain plane after bending. 

(196) 



Sees. 2632=2635 

(b) Beams and slabs shall be designed to resist safely the actual bending 
and shear produced by the loads and supporting forces under the existing 
conditions of end restraint or continuity. It is the intent of this part to 
require that the bending moments throughout the spans be determined so 
far as possible consistently with the elastic deformation of the structure, 
being in general calculated according to the provisions of section twenty-six 
hundred and thirty-five by methods of elastic analysis; but they may in the 
special cases and with the limitations described in section twenty-six hundred 
and thirty-six be approximated by the use of arbitrary moment coefficients 
as provided therein. Wherever negative bending may occur, the full amount 
thereof shall be provided for, except in slabs thirty inches or less in span. 

Sect. 2633. Span Length of Reinforced Concrete Members. — (a) 
The span length of freely supported beams and slabs shall be the distance 
between centers of bearings, but need not exceed the clear span plus the 
depth of beam or slab. 

(b) The span length for continuous or restrained beams and slabs built 
to act integrally with supports shall be the clear distance between faces of 
supports, the spaces occupied by supports where restraint or continuity 
occurs being suppressed in the force and moment diagrams. 

(c) For continuous beams having brackets built to act integrally with 
both beam and support and of a width not less than the width of the beam 
and making an angle of forty-five degrees or more with the beam, the span 
shall be measured from the section where the combined depth of the beam 
and bracket is at least one third more than the depth of the beam. Biackets 
making an angle of less than forty-five degrees with the beam may be con- 
sidered as increasing the effective depth of the beam, but not as decreasing 
the span length. Beams shall be designed to resist at each section the bending 
there occurring. 

(d) Maximum negative moments are to be considered as existing at the 
ends of the span, as defined above. 

*Sect. 2634. Depth of Reinforced Concrete Beam and Slabs. — (a) 

The effective depth of beams and slabs shall be taken as the distance from 
the center of gravity of the tensile reinforcement to the compressive surface 
of the structural member; except for monolithic beams and slabs where the 
top is a wearing surface, then the effective depth shall be taken to a plane 
one-half inch below the finished surface. 

(b) For beam and slab construction the total thickness for slabs shall 
not be less than three and one-half inches except as provided in sections 
twenty-six hundred fifty-three and twenty-six hundred fifty-nine. 
[ *As amended by Ord. 1943, ch. 8 } 

Sect. 2635. Analysis of Bending in Reinforced Concrete. — (a) 

The determination of bending moments to be provided for at various points 
in the span of a member restrained at supports, or a series of continuous 
spans, in accordance with section twenty-six hundred and thirty-two, shall 
be made by application of the theorem of three moments, principle of least 
work, or equivalent method based on elastic deformation, and shall be subject 
to the following qualifications: — 

(197) 



Sees. 2636=2638 



(1) Supports afforded by beams, girders and columns of usual arrange- 
ment shall be assumed to be and remain in alignment conforming to the 
position of the unloaded beam or slab. 

(2) The effect on bending moments in the spans produced by the 
torsional resistance of interior supporting beams and by the bending 
resistance of ordinary interior supporting columns may be neglected, 
and shall be neglected unless the restraint is computed and provided for 
in the 'supports. Restraint at exterior supports shall be provided for both 
in the spans and in the supports. 

(3) The difference in moment of inertia of beams of approximately 
the same depth in different spans and of the same beam acting to resist 
positive and negative bending, may be considered negligible so far as 
regards its effect on distribution of moment throughout the spans. The 
moment of inertia may be calculated from the gross section of the concrete 
neglecting reinforcement and the flanges of T-beams may be neglected. 

(4) Design for bending, both positive and negative, that may occur 
within a span shall include consideration of the effects of a partial distribu- 
tion of load on the span itself and either or both adjacent spans, but not 
on spans more remote than these. Maximum negative moment at a 
support may be assumed to result from full loading on adjacent spans only. 
(b) The commissioner may approve analyses conforming to the intent 

of this part, based on accepted theory, and incorporating refinements other 
than these provided herein; and he may require special analysis for extraor- 
dinary conditions of support, restraint, span lengths and distribution of load. 

Sect. 2636. Arbitrary Moment Coefficients for Reinforced Con= 
Crete. — (a) In the case of a beam or a slab, or a series of continuous beams 
or slabs with spans differing not more than twenty-five per cent of the longer 
span, uniformly loaded, and falling within one of the specified cases of restraint 
at the supports, designs may be made to resist bending moments computed 
by the arbitrary coefficients presented in this section, instead of by elastic 
analysis. 

(b) The coefficients of CwL 2 ) set forth in the following table may be used 
to compute the positive bending at mid-span and the negative bending at 
supports in the locations and under the conditions indicated. 

Table of Arbitrary Coefficients for Bending. 





Number 

of 
Spans. 


End Span. 


First 
Interior 
Support. 


Interior Spans. 


Conditions of Restraint. 


End 
Support. 


Mid- 
Span. 


Mid- 
Span. 


Other 
Interior 
Supports. 


Case 1 : Slabs or beams with 
negligible restraint at end 
supports. 

Case 2: Slabs or beams with 
moderate restraint at end 
supports. 

Case 3: Slabs or beams with 
full restraint at end sup- 
ports. 


{ * 

[ Mult. 

{ * 

{ Mult. 

{ » 

{ Mult. 


1/24 
1/24 
1/24 

1/16 
1/16 
1/16 

1/12 
1/12 

1/12 


1/8 

1/10 

1/12 

1/10 
1/12 
1/14 

1/12 
1/16 
1/16 


i/i" 

l/9i 

1/9 
1/10 

1/10 
1/11 


1/16 
1/16 
1/16 


1/12 
1/12 
1/12 



1 One tenth for slabs. 

(198) 



Sees. 2638=2640 

(c) In the use of this table negligible restraint shall be assumed for slabs 
supported on walls of masonry units, or on the upper flanges of steel beam3 
not encased in concrete; and for beams supported on steel or cast iron columns 
not encased in concrete, or on combination columns, or on masonry piers or 
walls of any type other than reinforced concrete columns acting integrally 
therewith, or by other beams or girders; or on any supports which do not 
assure as great restraint as that described as "moderate." 

(d) Moderate restraint may be assumed for slabs supported by rein- 
forced concrete beams, or by steel beams encased in concrete, or by reinforced 
concrete walls; and for beams or girders supported on composite columns, 
or on reinforced concrete columns, provided the slabs or beams act integrally 
with the support. 

(e) Full restraint may be assumed only for slabs acting integrally with 
supporting reinforced concrete walls and for beams or girders acting integrally 
with reinforced concrete columns, when (I/L) for the slab, beam or girder 
is less than the sum of the values of (I/h) for the walls or columns, respec- 
tively, above and below. In this section (I) represents the moment of 
inertia, calculated for the gross section of the concrete, neglecting reinforce- 
ment and the flanges of T-beams. (L) and (h) are span length and column 
or wall height, respectively. 

(f) In calculating negative bending at a support between two spans 
of unequal load or length, the average unit load over the two spans shall be 
used, and an assumed span which is two thirds the longer span plus one third 
the shorter span. 

(g) For continuous or restrained beams or girders subject to equal con- 
centrated loads which occur at approximately regular intervals with a con- 
centration at each support, the positive and negative bending may be deter- 
mined as though the entire load were distributed uniformly on the beam 
or girder. 

*Sect. 2637. Points of Inflection in Reinforced Concrete, and Shear. 

— The location of points of inflection, reactions and shears, shall be assumed 
consistently with the loading and the computed distribution of bending 
moments. In the three cases of slabs and beams of two or more continuous 
spans when the arbitrary coefficients for bending of section twenty-six hun- 
dred and thirty-six may be applied, the reactions on end supports shall be 
taken as forty per cent for Case 1, forty-five per cent for Case 2, and fifty 
per cent for Case 3, of the load on the end span, and the reaction on the first 
interior support shall be computed accordingly; the loads on interior spans 
majr be assumed as evenly divided between supports in determining shears 
and reactions. 

[ *As amended by Ord. 1943, ch. 8 ] 

Sect. 2638. Diagonal Tension in Reinforced Concrete Beams. — (a) 

Reinforced concrete beams (including ribs of ribbed and combination slabs, 
and other members subject to bending) shall be designed to resist the diagonal 
tension in their webs without exceeding the stresses prescribed in sections 
twenty-six hundred and twenty-nine and twenty-six hundred and thirty. 

(199) 



Sees. 2638=2640 

(b) For the purpose of design, the diagonal tension in the web of a beam 
shall be assumed to be directed at an angle of forty-five degrees with the 
axis of the beam, and its intensity to be equal to the unit shear, computed by 
the formula: 

V 

v = 

b'jd 

In this formula (b') is to be taken as the width of the concrete section 
between the tensile steel and the compressive flange, the average width 
if the sides slope but not over twenty per cent more than the minimum. 

(c) Beams in which the diagonal tension in any portion of the web exceeds 
the stress allowed in beams without web reinforcement shall be reinforced 
in that portion for the excess. 

Sect. 2639. Types of Web Reinforcement. — (a) Web reinforcement 
shall consist of vertical stirrups or of stirrups or bars inclined at an angle of 
not less than fifteen degrees with the axis of the beam. 

(b) Web reinforcement shall be considered effective only to the extent 
that its stress can be developed by bond and anchorage as provided in section 
twenty-six hundred and forty-six. 

Sect. 2640. Design of Web Reinforcement. — (a) A web reinforcing 
bar, whether vertical or inclined, shall be considered to afford for resistance 
to diagonal tension the component of its tensile stress in the direction of the 
diagonal tension. The spacing of stirrups (or the length of beam over which 
the resistance of a stirrup or bar is effective) is therefore determined by the 
following formula: 

A v f v jd (cos a + sin a) 

s = 

V 

For vertical stirrups this becomes — 

A v f v jd 
V 
and for stirrups or bars inclined at forty-five degrees — 

A v f v jd 



8 = 



0.7 V 



(b) In the formulas of this section (V) is the shear in the beam at any 
cross-section in excess of the allowed resistance of the unreinforced web, and 
it shall be subject to the limitation imposed upon the unit shear by section 
twenty-six hundred and twenty-nine. The spacing (s) of stirrups, vertical 
or inclined, or of bars inclined at not less than forty-five degrees shall not 
exceed three fourths the effective depth of the beam. In the case of bars 
inclined at less than forty-five degrees, (s) shall not exceed three fourths the 
axial projection of the inclined length. 

(200) 



cs. 2640=2643 

(c) In portions of beams where the unit shear exceeds (0.06 f' c ) the 
limits for (s) shall be reduced by changing the fraction three-fourths to one- 
half in the preceding paragraph. 

Sect. 2641. Shearing Stress in Concrete Flat Slabs. — (a) In flat 
slabs, the shearing unit stress on a vertical section which lies at a distance 
(d) from the edge of the column capital and parallel with it, shall not exceed 
the following allowable values when computed by the formula given in section 
twenty-six hundred and thirty-eight for shearing unit stress in beams. 

(1) 0.03 f' c — when at least fifty per cent of the total negative rein- 
forcement in each column strip passes directly over the column capital. 

(2) 0.025 f ' c — when twenty-five per cent of the total negative rein- 
forcement in each column strip passes directly over the column capital 
(which is the least that shall be permitted). 

(3) For intermediate percentages, proportionate intermediate values of 
the allowable shearing unit stress shall be used. 

(b) In flat slabs, the shearing unit stress on a vertical section which lies 
at a distance (d) from the edge of the dropped panel and parallel with it shall 
not exceed (0.03 f' c ). 

(c) For the purposes of this section (d) shall be the average depth at the 
section in question from the compressive surface of the concrete to the center 
of the tensile reinforcement for negative bending. 

Sect. 2642. Shear and Diagonal Tension in Footings. — (a) The 

shearing unit stress computed by the formula given in section twenty-six 
hundred and thirty-eight on any vertical peripheral or plane section of a 
footing at a distance (d) from the face of the supported column or pier and 
parallel with it, shall not exceed (0.02 f ' c ) for footings with straight bars, nor 
(0.03 f'c) for footings in which the bars have special anchorage as specified in 
section twenty-six hundred and forty-five. 

(b) Id footings supported on piles, the critical section for diagonal tension 
shall be considered at a distance (d/2) from the face of the supported col- 
umn or pedestal and any piles whose centers are at this section or nearer the 
supported column or pedestal shall be excluded in computing the shear. 

Sect. 2643. Bond Stress in Reinforced Concrete. — (a) Members 
subject to bending shall be so proportioned that the increments of stress in the 
tensile steel are transmitted to it from the concrete in which it is embedded, 
without producing bond stress exceeding that specified in section twenty-six 
hundred and twenty-nine. 

(b) In beams in which the tensile reinforcement is parallel to the com- 
pressive face, and is not specially anchored, the bond stress (u) shall be 
assumed to be determined by the following formula: — 

V 
u = 

gjd 

(c) In non-prismatic or wedge-shaped beams, as represented by a canti- 
lever bracket, a sloped top footing, or a beam with cambered compressive 
face, in which the depth of the beam is increased in the direction of increasing 

(201) 



Sees, 2643=2644 

bending moment, the bond stress is not proportional to the shear, being at all 
sections smaller than indicated by the formula of paragraph (b) for a pris- 
matic beam of depth equal to the depth at the section considered. For such 
beams the bond stress shall be assumed to be determined by the following 
formula: — 

V M 

u = X (1 - m ) 

gjd Vd 

in which (m) is the tangent of the angle between the compressive face and 
the tensile re-inforcement. 

(d) Adequate end anchorage of bars in prismatic beams which are sub- 
ject to excessive bond stress, as computed by the formula of paragraph (b), 
may result in the relief of such excessive bond stress, by inducing in the beam 
an arch action, with distribution of bending stresses analogous to that in a 
cambered beam. About bars so anchored the computed bond stress may be 
double that allowed for unanchored reinforcement. 

(e) Special anchorage adequate to justify increased bond stress shall be 
capable of developing the maximum tension in the bars in excess of that 
developed by bond at its allowable value. The excess tension (T') shall be 
determined by the formula: — 

u' 

T' = T (1 ) 

u 

in which (T) is the maximum tensile stress. 

(u') is the allowable stress in bond for unanchored reinforcement, 
(u) is the maximum bond stress computed by one of the formulas of 
paragraphs (b) and (c). 

(f ) In simply supported beams the required special anchorage shall be pro- 
vided beyond the face of the support. In continuous beams sufficient special 
anchorage of the positive reinforcement beyond the point of inflection may be 
considered to be provided by the extension of such bars to the ends of the 
span. For the negative reinforcement of restrained or continuous beams, 
and for the tensile reinforcement of cantilevers, brackets and footings, the 
required special anchorage shall be provided by extending or hooking the bars 
beyond the point at which tension begins. 

(g) In applying the formulas of paragraphs (b) and (c) to any section of 
a beam in which the tensile reinforcement is varied by bending or discon- 
tinuing a portion of the bars, there shall be counted as contributing their 
perimeters to bond resistance only those bars at that section and in the plane 
of the main longitudinal tensile steel, in which tensile stress is increasing 
consistently with the assumptions under which the beam is designed. 

Sect. 2644. Ordinary Anchorage of Reinforcement. — (a) Rein- 
forcement acting in tension at a restrained end of a beam or in a cantilever 
shall have anchorage on both sides of the face of the support and beyond the 
point where any portion of the reinforcement is discontinued sufficient to 
develop the tension in each of the bars. 

(202) 



Sees. 2644-2646 

(b) In a restrained beam at least one third of the tensile reinforcement 
for negative bending shall be extended at least to the point of inflection of the 
beam. 

(c) At least one fourth of the tensile reinforcement for positive bending 
in a beam shall be extended at least to the end of the span. Bars not so 
extended may be bent across the web, becoming continuous with the nega- 
tive reinforcement, or otherwise anchored in a region of compression. 

Sect. 2645. Special Anchorage of Reinforcement. — (a) Where, by 
reasons of 'special anchorage of reinforcement, increased shearing stresses are 
allowed, reinforcement in the proportions specified in section twenty-six 
hundred and forty-four shall be extended in beams as there specified, and 
anchorage shall further be provided beyond the points of inflection for the 
negative reinforcement of restrained beams, and beyond the end of the span 
for positive reinforcement of freely supported beams, sufficient to develop 
at least one half of their allowable tensile stress. In footings, special anchor- 
age justifying increased shearing stress shall be considered as provided when 
all bars are anchored by means of hooks at their ends. The outer face of 
hooks shall be as close to the face of the footing as the requirements for rust 
protection will allow. 

(b) Where anchorage is furnished by extension of the bars, such exten- 
sion may be assumed to provide an anchorage capacity equal to the embedded 
surface multiplied by the allowable unit bond resistance specified in section 
twenty-six hundred and twenty-nine. A hook, for the purpose of this section, 
means a complete semicircular hook as defined in section twenty-six hundred 
and two. Such a hook may be assumed to develop a stress of not more than 
ten thousand pounds per square inch in the bar so anchored. A bend of 
larger radius than allowed in a hook shall be considered as a mere extension 
of the bar. 

Sect. 2646. Anchorage of Web Reinforcement. — (a) The stress in a 
stirrup or web reinforcement bar for resistance of diagonal tension in a beam 
shall not exceed the capacity of its anchorage in the upper or lower one half 
of the effective depth of the beam nor the allowable stress specified in section 
twenty-six hundred and thirty. 

(b) Web reinforcement which is provided by bending into an inclined 
position one or more bars of the main tensile reinforcement where not required 
for resistance to positive or negative bending shall be considered completely 
anchored by continuity with the main tensile reinforcement or by embed- 
ment of requisite length in the upper or lower half of the beam, provided at 
least one half of such embedment is as close to the upper or lower surface 
of the beam as the requirements of fire or rust protection allow. A hook 
placed close to the upper or lower surface of the beam may be substituted 
for a portion of such embedment. 

(c) Stirrups shall be anchored at both ends by one of the following methods 
or by a combination thereof: — 

(1) Rigid attachment, as by welding, to the main longitudinal rein- 
forcement. The capacity of this anchorage is limited to that of the attach- 
ment. 

(203) 



Sees. 2646=2650 

(2) Bending around and closely in contact with, a bar of the main 
longitudinal reinforcement in the form of a U-stirrup or a hook. The 
capacity of this anchorage may be taken as sixteen thousand pounds per 
square inch in the stirrup. 

(3) A hook placed as close to the upper or lower surface of the beam 
as the requirement for fire and rust protection will allow. The capacity 
of this anchorage shall be ten thousand pounds per square inch in the 
stirrup plus the stress developed by bond between mid-height of the effec- 
tive depth of the beam and the beginning of bending of the hook. 

(4) A length of embedment in the upper or lower half of the effective 
depth of the beam, whether straight or curved. The capacity of this 
anchorage shall be limited to the stress developed by bond on the embedded 
length. Anchorage of this type shall not be used on stirrups where the 
unit shear exceeds (0.06 f' c )« 

Sect. 2647. Slenderness of Reinforced Concrete Beams. — The 

clear distance between lateral supports of a beam shall not exceed thirty-two 
times the width of the compression area of the cross-section. 

Sect. 2648. T=Beams of Reinforced Concrete. — (a) In T-beam con- 
struction the slab shall be built integrally with the beam. In the design 
of symmetrical T-beams the overhanging flange width on either side of the 
web shall not exceed one tenth the span, nor eight times the thickness of 
the slab nor one half the clear distance to the next beam. 

(b) For beams having a flange on one side only, the effective overhanging 
flange width shall not exceed one twelfth of the span length nor six times 
the thickness of the slab nor one half the clear distance to the next beam. 

(c) Where the principal reinforcement in a slab which serves as the flange 
of a T-beam (not a rib in ribbed floors) is parallel to the beam, transverse 
reinforcement shall be provided in the top of the flange. The spacing of the 
bars shall not exceed five times the thickness of the flange, or eighteen inches. 

(d) Isolated beams in which the T-form is used only for the purpose of 
providing additional compression area, shall have a flange thickness not less 
than one half, and a total flange width not more than four times, the web 
thickness. 

Sect. 2649. Compression Reinforcement in Beams and Girders. — 

Steel reinforcing bars in compression in girders and beams shall be thoroughly 
anchored against buckling by ties or stirrups not less than one quarter inch 
in diameter spaced not further apart in the region where compression steel is 
required than twelve times the diameter of the bars, or by equivalent lateral 
support. 

*Sect. 2650. Structural Steel Beams Encased in Concrete. — (a) 

Structural steel beams which are fireproofed by being wholly encased in the 
concrete of a reinforced concrete floor or roof may be designed for bending 
as composite beams, the two materials assumed to act elastically together, 
the concrete not to act in tension, the stresses in the respective materials not 
to exceed those allowed by this code. 

(204) 



Sees. 2650=2652 

(b) Any steel beam or girder completely encased in concrete as described 
in paragraph (a) having a compressive strength of at least two thousand 
pounds per square inch and comprising an integral part of a complete floor 
system such as concrete slabs and beams, in conformity with section twenty- 
six hundred and forty-eight, may have its resistance to bending increased 
fifteen per cent. 

(c) Stresses allowed in paragraph (b) shall be allowed in tension members 
of trusses, if the requirements of this section are fulfilled. 

[ *As amended by Ord. 1943, ch. S ] 

Sect. 2651. Shrinkage and Temperature Reinforcement. — (a) 

Reinforcement for shrinkage and temperature stresses shall be provided in 
floor and roof slabs perpendicular to the reinforcement for bending where 
this runs in one direction only. Such reinforcement shall have an area of 
cross-section not less than two one thousandths times the area of the concrete 
and bars shall be spaced not more than five times the slab thickness nor more 
than eighteen inches. 

(b) In reinforced concrete spandrel beams and parapet walls shrinkage 
reinforcement shall be provided, in amount not less than one half of one per 
cent, in addition to the reinforcement for bending. Such reinforcement 
shall be continuous and rods shall be spliced by lapping or otherwise, except 
at expansion joints. 

(c) Consideration shall be given to the stresses due to expansion and 
shrinkage in buildings more than two hundred feet long and provision shall be 
made satisfactory to the commissioner for avoiding excessive stress. In 
buildings longer than four hundred feet expansion joints shall be provided not 
more than three hundred feet apart. Such joints shall be constructed with 
at least one inch opening and shall allow for expansion of each section of 
building not less than one half inch for every one hundred feet of its length. 

Sect. 2652. Concentrated Loads on Concrete Slabs. — (a) For 

computation of stresses due to bending and shear, concentrated loads on 
one-way slabs may be considered as evenly distributed over an effective 
width at right angles to the direction of the span as follows : — 

Solid concrete construction . . . w -f- 0.8 s 

Combination floor construction . . w + 0.6 s 

Ribbed floor construction . . . w + 0.4 s but not more than 

w + twice the rib spacing 
where (w) is the actual width of the concentration and (s) is the distance from 
the nearer support to the center of the concentration. For concentrations 
at mid-span or for loads such as partitions which are concentrated laterally 
but distributed longitudinally to the span, (s) shall be taken as equal to 
half the span. 

(b) If adequate bridging is provided to distribute concentrations among 
adjacent ribs, the effective width for combination and ribbed slabs may be 

(205) 



Sees. 2652=2653 

taken as for solid slabs, but in the case of ribbed slabs, unless the bridging 
has approximately the same spacing as the ribs, not more than three adja- 
cent ribs shall be assumed to share the Joad. 

*Sect. 2653. Concrete Ribbed and Combination Slabs. — (a) 

Ribbed floor construction consists of concrete ribs, running in one or two 
directions and topping placed monolithically with the ribs, not over twenty 
inches apart between faces. The ribs shall be straight and of a width not less 
than four inches nor less than one third the depth. The topping shall be of 
sufficient strength to transmit loads coming upon it to the adjacent ribs 
and shall be not less than two inches thick. Ribbed slabs shall be reinforced 
at right angles to the ribs with a minimum of forty-nine one thousandths 
square inch of reinforcing steel per foot and in slabs on which the prescribed 
live load does not exceed fifty pounds per square foot, no additional rein- 
forcement shall be required. 

(b) Combination floor construction consists of concrete ribs running in one 
or two directions, with masonry fillers, filling the entire space between ribs, 
and either with or without a monolithic concrete topping over the ribs. Each 
masonry filler shall have contact with ribs on two opposite sides. Ribs shall 
be not over twenty inches apart between faces, shall be straight and of a 
width not less than four inches nor less than one third the depth. Either the 
fillers or the topping over them, or the combination of the two shall be of 
sufficient strength to transmit any load coming on them to the adjacent 
ribs. If a monolithic topping is used, it shall be not less than one inch thick. 

(c) If structural fillers as specified in paragraph (e) are used, then, and 
not otherwise, certain portions of them may be included with the concrete in 
calculations of resistance to shear and bending, but the amount included shall 
nowhere exceed the actual thickness of the portion of the filler nor one and one 
half inches. In one-way construction the webs of structural fillers which are 
in contact with the concrete ribs and where there is a topping the web in 
contact therewith may be included with the concrete in calculations of re- 
sistance to shear and bending. In construction in which the ribs run in both 
directions and at approximately the same distance on centers, and whether 
designed as one-way or two-way slabs, the webs in contact with the concrete 
ribs may be included in calculations of resistance to shear and bending and 
the top and bottom webs may be included in calculations of resistance to 
bending. 

(d) The maximum stress in both the concrete and the filler shall not 
exceed that allowed.in the weaker of the two materials. 

(e) A structural filler, for the purpose of this section, shall have an ultimate 
strength in compression, on its net section, when tested on end at the age of 
twenty-eight days, of two thousand pounds per square inch. If structural clay 
tiles are used as fillers they shall at least equal those classified as Grade B in 
Part 24 of this code. Gypsum tile shall not be used as a structural filler. 

(f) The unit extreme compressive fibre stress in the filler tile shall not 
exceed four tenths of its ultimate unit compressive strength, determined for 
the net section from an average of three fillers tested on end at an age of 

(206) 



Sees. 2653=2654 

twenty-eight days. The unit stress allowed in shear computations shall not 
exceed one quarter of the average ultimate strength in shear of the joint 
between the ribs and the filler blocks. 

(g) Where the topping contains conduits or pipes, the thickness shall 
not be less than one inch plus the total overall depth of such conduits or pipes 
at any point. Such conduits or pipes shall be so located as not to impair the 
strength of the construction. 

(h) Shrinkage reinforcement shall be provided in the slab as required in 
section twenty-six hundred and fifty-one. 

(i) Neither paper, wood, nor roofing material shall be used between or at 
the ends of structural hollow masonry fillers included in calculations of re- 
sistance to shear or bending to prevent concrete from flowing into the inter- 
stices thereof, nor any other material that would impair the bond between 
the end of the filler and the concrete, but this shall not prevent the use of 
such materials when inserted in but not projecting from the openings of the 
fillers nor the use of the same material that is permitted for the fillers them- 
selves. If concrete is allowed to penetrate the interstices of hollow masonry 
fillers, the weight thereof shall be included in the dead load to be supported. 
The webs of structural filler units whose ends are thus in contact with the 
concrete may be included in calculations of resistance to bending. 
[ *As amended, by Ord. 1948, ch. 8 ] 

fSect. 2654. Two=Way Slabs of Reinforced Concrete. — (a) Con- 
crete slabs, either solid, ribbed or combination slabs, supported on four sides 
by beams, girders or walls, and reinforced to span in two directions shall be 
designed in accordance with the provisions of this section. 

(b) The slab shall be regarded as consisting of a series of adjacent strips 
of unit width spanning in each direction. In computations for shear and 
diagonal tension, bond, and for the loading of supporting members, each strip, 
spanning in either the longer or the shorter direction, shall be assumed to 
carry and transmit to its supports a total load (W), represented by the expres- 
sion: 

W = 1/2 C r w L = 1/2 C w U 

in which (w) is the total load per unit area of the slab. 

(L) is the span of the strip. 

(Li) is the width of the panel transverse to the span. 

(r) is the ratio of Li to L. 

(Co) is a coefficient dependent on the position of the panel relative 
to adjacent panels continuous with it at its ends and sides, 
as indicated on the accompanying diagram. Full restraint 
at end support, as defined in section twenty-six hundred and 
thirty-six, shall be considered equivalent to continuity in 
determining (C ). 

(207) 



Sees. 2654=2655 



MARGINAL BEAM OR WALL 




t 




1.0 


o.<? 




I.I 


1.0 











z 

o 
o 
u 

s 



o 
m 

< 

h 

Ui 

> 
z 



Of 

z 

GO 



J 
J 

i 

o 
< 

IU 

£0 

J 

< 

z 
3 

< 

I 

VALUES OF C )hi VARIOUS PANEL.5. 

(c) The positive bending moment for a strip of unit width in the middle 
half of the panel, spanning in either direction, shall be assumed as given by 
the following formula: — 

M = 0.33 CiC r 2 wL 2 = 0.33 GC wLi 
in which (Ci) is a coefficient for bending determined in accordance with the 
conditions of restraint at end supports of the strips as provided in section 
twenty-six hundred and thirty-five or section twenty-six hundred and thirty-six. 

(d) Negative moments at and adjacent to supports between two panels 
shall be determined by the formula given in paragraph (c) for positive moment 
taking (Ci) as the coefficient for negative moment determined according 
to section twenty-six hundred and thirty-five or section twenty-six hundred 
and thirty-six, and in case the conditions of continuity in the two panels are 
different, taking the mean value of (C ). 

(e) The positive bending in strips of unit width in the outer quarters of 
the panel may be assumed to be three quarters that of the strips of the middle 
half. 

(f) Lines of inflection in a two-way panel shall be assumed at a distance 
of one fourth of its shorter span from supports over which the slab is con- 
tinuous. 

[ ]As amended by Ord. 1943, ch. 8 ] 
{Sect. 2655. Limitations upon Reinforced Concrete Flat Slabs. — 
(a) The term "flat slabs" as used herein refers to concrete slabs with rein- 
forcing bars in two or more directions, whose interior supports are columns 
or the like, generally without beams. 

(208) 



Sec. 2655 

(b) The methods of stress computation herein specified apply to a series 
of slabs of approximately uniform size extending at least three panels in each 
direction and in which the length of panel does not exceed one and one half 
times its width. Flat slabs of other arrangement shall be proportioned to 
have at least equal carrying capacity and degree of safety according to estab- 
lished principles of mechanics. 

(c) Flat slabs with paneled ceiling or with dropped panels may be pro- 
portioned by the methods herein specified provided the dropped panel shall 
have a length or diameter in each rectangular direction not less than one third 
the panel length in that direction, and the thickness of the thicker portion of 
the slab shall not exceed one and one half times that of the remainder. In 
the ceilings of flat slabs, concrete between rods in tensile regions and in com- 
pressive regions where it can be spared may be displaced by permanent or 
removable fillers, provided allowable stresses are not exceeded in the concrete 
which remains and provided the tensile stress in the reinforcing rods in that 
region shall not exceed eight ninths the stress allowed in the reinforcement of 
solid concrete slabs. Compression concrete above such fillers shall have a 
thickness not less than two inches, and the construction shall safely support 
any concentration of load that may come upon it. The term "slab thickness " 
used in connection with such construction shall refer to the total thickness of 
the structural concrete. 

(d) Column capitals, if of concrete, shall be of the mixture required for 
the column up to a level where the area of a horizontal section is fifty per 
cent more than the gross area of the shaft of the column. In dimensioning 
the concrete capital for design purposes, no portion of the capital shall be 
considered which lies outside the largest ninety-degree circular cone contained 
within its outlines. The diameter of the capital shall be measured for design 
purposes at the junction of the cone with the bottom of the slab or dropped 
panel. 

(e) Column capitals of structural metal may be substituted for concrete 
capitals, whether contained within the thickness of the slab and dropped 
panel, or not, provided they meet the following requirements: — ■ 

(1) they shall have the same protection against fire required for rein- 
forcement in similar exposures; 

(2) they shall safely support the slab on the periphery of the capital 
without exceeding stresses allowed in this code for the kind of metal used; 

(3) they shall provide support for the slab or dropped panel at a dis- 
tance above the bottom thereof not substantially greater than the require- 
ments for fire protection, and such support shall either be continuous along 
the periphery of the capital or with intervals not greater than three times 
the thickness of concrete slab, or slab and dropped panel; 

(4) the capitals shall be so designed and arranged as to permit the proper 
placement of concrete in and about them without pockets or voids, and to 
provide for the transmission of load from columns above to columns below; 

(5) the diameter of a structural metal column capital, for purposes of 
slab design, shall be taken as twice the distance from the center of the 
column to the center of bearing of slab or dropped panel on a continuous 

(209) 



Sees. 2655=2657 

circumferential support, or twice the average distance to centers of bearing 
on radial or non-continuous supports, the unit bearing assumed as uniform 
and not in excess of the stress allowed by this code. 
[ %As amended by Ord. 1943, ch. 8 ] 

Sect. 2656. Assumptions in Concrete Flat Slab Design. — (a) 

A flat slab panel shall be considered as consisting of strips, parallel to sides 
of the panel, as follows: — 

(1) A middle strip one half panel in width, symmetrical with respect 
to the panel center line. 

(2) A column strip one half panel in width made up of two quarter- 
panel areas outside the middle strips. 

(3) The strips shall be considered in each rectangular direction for the 
computation of bending moments. 

(b) The critical sections for bending are referred to as the principal 
design sections and are located as follows: — 

(1) Sections for negative bending shall be taken along the edges of the 
panel at ends of the strips, on center lines of columns, and around the 
periphery of the column capital. 

(2) Sections for positive bending shall be taken at mid-length of the 
strips, on the center line of the panel. 

*Sect. 2657. Bending in Interior Flat Slab Panels. — (a) The 

numerical sum of the positive and negative bending moments in either 
rectangular direction of an interior panel, for the design of tensile reinforce- 
ment, shall be assumed as not less than — 

(2c\2 
1 ) = M pc + M pm + M no + M nm 
3L/ 

where (M pc ) is the positive moment at mid-span of the column strip. 
(M pm ) is the positive moment at mid-span of the middle strip. 
(M nm ) is the negative moment at one end of a middle strip. 
(M nc ) is the negative moment at one end of the column strip. 
(L) is the length of the strips between center lines of columns, 

(c) is the diameter of the column capital, or top of column if 

there is no capital. 
(W) is the total live and dead load uniformly distributed over 

a single panel area. 

(b) The bending moments for the design of tensile reinforcement in the 
principal design sections shall be assumed to be those given in the following 
table, except that (M nc ) may be (0.03 M ) greater or smaller, and each of 
(M pP ), (Mpm) and (M nm ) may be (0.01 M ) greater or smaller provided that 
the sum remains not less than the value specified for (M ). 

(c) If a flat slab is supported at interior column points by supports less 
rigid than the columns specified in section twenty-six hundred and sixty-nine > 
paragraph (b), the positive bending in column and middle strips shall be 
increased twenty per cent above the tabular values. 

(210) 



Sees. 2658=2660 



Bending Moments in Flat Slabs for Tensile Reinforcement — Interior 

Panels Fully Continuous. 





Two-way Reinforcement. 


Four-way Reinforcement. 


Moment. 


Without 
Dropped Panel. 


With 
Dropped Panel. 


Without 
Dropped Panel. 


With 
Dropped Panel. 


M P c 


0.22M o 


0.20Mo 


0.20M<> 


0.19M o 


Mpm 


O.I6M0 


0.15M o 


0.20Mo 


0.19M o 


Mnc 


0.46M o 


0.50Mo 


0.50M o 


0.54M o 


Mnm 


0.16M o 


0.15M o 


O.lOMo 


O.O8M0 



[ *As amended by Ord. 1948, ch. 8 ] 

Sect. 2658. Spacing of Flat Slab Reinforcement. — (a) Bands of 
rods in two-way systems of reinforcement shall be spread evenly over the 
width of the strips. 

(b) Direct bands of rods in four-way systems shall have a width of about 
(0.4) times the panel width, diagonal bands (0.4) times the average panel 
widths, and the rods shall be spread evenly in the bands. 

(c) The maximum spacing of rods shall not exceed three times the thick- 
ness of the slab. 

fSect. 2659. Thickness of Concrete Flat Slabs. — (a) The thickness 
of a flat slab, and the size and thickness of the dropped panel shall be such 
that the compressive stress due to bending will not exceed that allowed for 
concrete on the principal design sections of any strip. The bending moments 
for which the compressive stress shall be computed shall be assumed to be 
four thirds those specified for the design of reinforcement. 

(b) The width of section for computing compression in concrete due to 
negative bending at the column head shall be taken as the width of the dropped 
panel if any; otherwise, half the panel width. The width of other principal 
sections shall be taken as half the panel width. 

(c) The thickness of the slab and the size and thickness of the dropped 
panel shall be such that shearing stresses computed as specified in section 
twenty-six hundred and forty-one shall not exceed the stress allowed. 

(d) In no case, however, shall the slab thickness be less than one fortieth 
the length of the panel nor less than six inches. 

[ 1[As amended by Ord. 1943, ch. 8 ] 

Sect. 2660. Point of Inflection in Flat Slabs. — (a) In a middle 
strip the point of inflection for slabs without dropped panels shall be assumed 
at a line (0.33L) distant from the center of the span and for slabs with dropped 
panels (0.3L) distant from the center of the span. 

(b) In a column strip, the point of inflection for slabs without dropped 
panels shall be at a line 0.33 (L-c) distant from the center of the panel and 0.3 
(L-c) for slabs with dropped panel. 

(211) 



Sees. 2661=2663 

Sect. 2661. Arrangement of Flat Slab Reinforcement at Column 
Heads. — Reinforcement shall be provided not only for the moments at 
principal design sections but also for moments at intermediate sections. 
Steel of the full area required for negative moment at the column head shall 
be continued in the same plane close to the upper surface of the slab to the 
edge of the dropped panel, and not less than a distance (0.2L) from the center 
line of the column. Lapped splices shall not be permitted at or near regions 
of maximum stress except as described in section twenty-six hundred and 
twenty-six. 

Sect. 2662. Arrangement of Flat Slab Reinforcement — Two=way 
System. — (a) In column strips at least four tenths of the area of steel 
required at the principal design section for positive moment in the strip 
shall be in bars of such length and so placed as to reinforce the sections for 
negative moment at the adjacent column heads. These bars, and other bars 
for negative reinforcement shall extend into the adjacent panel to a point 
at least (0.05L) beyond the point of inflection. Not less than one third of 
the bars used for positive reinforcement in the column strip shall be straight 
and extend into the dropped panel at least twenty diameters of the bar, but 
not less than twelve inches; or if no dropped panel is used, shall extend to 
within (0.125L) of the center line of the columns. The remainder of the 
bars for positive reinforcement in the column strip shall extend at least 
(0.33L) on either side of the center line of panel. Not less than one fourth 
in area of the bars for negative reinforcement of each column strip shall lie 
directly over the column capital and not less than one half within the width 
of the dropped panel, if any. 

(b) In the middle strip at least one half of the bars for positive moment 
shall be bent up for negative moment and extend over the bands of the 
column strips at both sides of the panel to a point at least (0.25L) beyond the 
center line of columns. The location of the bends shall be such that for a 
distance (0.15L) for slabs with dropped panels, and (0.1 25L) for slabs without 
dropped panels, on each side of the center line of columns, the full reinforce- 
ment required for negative moment will be provided in the top face of the 
slab. The full reinforcement for positive moment in the middle strip shall 
extend in the bottom face of the slab to a point at least (0.25L) on either 
side of the panel center line, and at least one half of it shall extend to points 
(0.325L) on either side of the panel center line for slabs with dropped panels, 
and (0.35L) for slabs without dropped panels. 

Sect. 2663. Arrangement of Flat Slab Reinforcement — Four=way 
System. — (a) Provisions governing the placing of steel in column strips 
in two-way systems apply as well to the direct bands in four- way systems. 

(b) In diagonal bands, at least four tenths of the area of steel required 
at the section for positive moment shall be in bars of such length and so 
placed as to reinforce the negative moment section at the two diagonally 
opposite column heads. These bars and other bars for negative reinforce- 
ment, if any, shall extend into the adjoining panel to points at least (0.4L) 
beyond a line drawn through the column center perpendicular to the direc- 

(212) 



Sec. 2663=2665 



tion of the band. The straight bars for positive moment in the diagonal 
bands shall not be shorter than the length of panel center to center of columns, 
(c) For negative moment in the middle strip, the required steel shall 
extend not less than (0.25L) on either side of the column center line. 

*Sect. 2664. Flat Slab Reinforcement Other than Two=way or 
Four=way. — Arrangement of reinforcement other than two-way or four- 
way shall provide reinforcing at the principal design sections and at inter- 
mediate sections equivalent to that specified above. All such arrangements 
shall be subject to the approval of the commissioner. 

[ *As amended by Ord. 1943, ch. 8 ] 

Sect. 2665. Discontinuous Flat Slab Panels. — (a) In panels ad- 
jacent to an exterior wall and other panels where the slab is discontinuous 
on one or two of its edges, the bending on principal design sections parallel 
to a discontinuous edge shall be assumed at values not less than specified in 
this section, depending upon the degree of restraint in bending furnished by 
the support at such discontinuous edge. 

(b) The numerical sum of the positive bending moment at mid-span and 
the average of the negative bending moments at the discontinuous edge and 
at the first interior supports for a full panel width, for the design of tensile 
reinforcement, shall be assumed as not less than 

c ~l~ a ^ 
Mo = 0.10 WL I 1 



/ c+aV 



in which (L) is the span center to center of columns, walls or other supports; 
(c) is the diameter of the interior column capital and (a) is the thickness of 
the exterior support in the direction of the span. A bracket on the inner 
face of an exterior column shall be ignored in determining the value of (a). 

(c) The bending moments for the design of tensile reinforcement in the 
principal design sections of the several strips shall be assumed, within the 
range of allowable variation specified in paragraph (b) of section twenty-six 
hundred and fifty-seven, as follows: — 

Bending Moment for Tensile Reinforcement in Wall Panels of Flat 

Slabs. 



Moment. 



Two-way Reinforcement. 



Without 
Dropped Panel. 



With 
Dropped Panel. 



Four-way Reinforcement. 



Without 
Dropped Panel. 



With 
Dropped Panel. 



Negligible Restraint at Discontinuous Edge. 



Mp 


0.32M o 


0.31M o 


0.30Mo 


0.29M o 


M pm 


0.26M o 


0.25M o 


0.30Mo 


0.29Mo 


Mnc (ext.) 


0.05M o 


0.05M o 


0.05Mo 


0.05Mo 


Mnm (ext.) 


0.05M o 


0.05Mo 


0.05Mo 


0.05M o 


Mnc (int.) 


0.55M o 


O.6OM0 


O.6OM0 


0.65M o 


Mnm (int.) 


0.19M o 


O.I8M0 


O.lOMo 


0.09Mo 






(213) 







Sec. 2665 

Bending Moment for Tensile Reinforcement in Wall Panels of Flat 

Slabs. — Continued. 



Moment. 



Two-way Reinfobcement. 



Without 
Dropped Panel. 



With 
Dropped Panel. 



Foub-way Reinfobcement. 



Without 
Dropped Panel. 



With 
Dropped Panel. 



Modeeate Restraint at Discontinuous Edge. 



Mp C 


0.29Mo 


0.27M o 


0.26M o 


0.25M o 


M pm 


0.23M o 


0.22M 


0.26M o 


0.25M o 


Mnc (ext.) 


0.22Mo 


0.23M o 


0.25M o 


0.26M o 


Mnm (ext.) 


O.O8M0 


O.O8M0 


O.O6M0 


O.O6M0 


Mnc (int.) 


0.50M o 


0.55M o 


0.55M o 


O.6OM0 


Mnm (int.) 


O.I8M0 


O.I6M0 


O.lOMo 


O.O8M0 



Full Restraint at Discontinuous Edge. 



M po 


0.25M o 


0.22Mo 


0.22M o 


0.2lMo 


M pm 


0.20Mo 


0.20Mo 


0.22Mo 


0.21Mo 


Mnc (ext.) 


0.38M o 


0.4lMo 


0.46M o 


0.48M o 


Mnm (ext.) 


O.lOMo 


O.lOMo 


O.O6M0 


O.O6M0 


Mnc (int.) 


0.46M o 


0.50Mo 


0.50Mo 


0.54M o 


Mnm (int.) 


O.I6M0 


0.15M o 


O.lOMo 


O.O8M0 



(d) If restraint at a discontinuous edge is furnished by a wall, the negative 
bending at the exterior support may be more nearly evenly distributed 
between column and middle strips. If the supports at interior column points 
are less rigid than the column specified in section twenty-six hundred and 
sixty-nine the positive bending in column and middle strips shall be increased 
twenty per cent above the tabular values. 

(e) Negligible restraint in bending at the discontinuous edge of a flat slab 
panel shall be considered to be furnished by a supporting wall of masonry or 
a row of masonry piers or by any support that does not assure as great 
restraint as that specified as moderate. 

(f) Moderate restraint shall be considered to be furnished by a wall of 
reinforced concrete or by a row of reinforced concrete columns or of steel 
columns encased in concrete when the slab acts integrally with the support 
and when the support is not sufficiently rigid to afford full restraint. 

(g) Full restraint shall be assumed where the discontinuous edge of a 
flat slab is supported by a reinforced concrete wall or row of columns with 



which it acts integrally and when the ratio ( — ) for the slab is less than the sum 

Li 
I 

of the ratios (-) for the walls or columns, respectively, above and below the 
h 

(214) 



Sees. 2665=2666 

slab. For the purpose of this section (I) is the moment of inertia of the slab, 
wall or column calculated for the gross area of the concrete and neglecting 
the reinforcement. 

(h) Except in the case of negligible restraint where precautions are taken 
to avoid restraint, the bending incidental to the restraint shall be trans- 
mitted to the supports, with or without the aid of brackets, in such manner 
that the stresses specified in this code for the materials used shall not be 
exceeded. The supports shall be made capable of resisting the bending 
so transmitted in addition to their other loads and forces without excessive 
stress. The bending moments transmitted shall be assumed to be four 
thirds those specified in this section for design of the tensile reinforcement 
of the slab. 

(i) The reinforcement for positive bending perpendicular to the dis- 
continuous edge shall extend to this edge and have an embedment of at 
least six inches in spandrel beams, walls or columns. Reinforcement for 
negative bending shall be bent or hooked at spandrel beams, walls or columns 
to provide adequate anchorage. The length and placement of other rein- 
forcement in wall panels shall be adapted from the requirements of sections 
twenty-six hundred and sixty-one, twenty-six hundred and sixty-two and 
twenty-six hundred and sixty-three having in view the changed location of 
the points of inflection. 

(j) The half column strip parallel and adjacent to a marginal beam 
having a depth not greater than one and one half times the slab thickness, 
or parallel and adjacent to a discontinuous edge without marginal beam, shall 
be designed to resist at least one half the moments specified for a full interior 
column strip. The half column strip parallel and adjacent to a marginal 
beam having a depth greater than one and one half times the thickness of the 
slab, shall be designed to resist at least one fourth the moments specified for 
a full column strip. 

(k) If a flat slab is supported at a discontinuous edge by a row of columns 
having brackets extending from the side of the column in a direction parellel 
to the discontinuous edge which are equivalent to column capitals, the value 
of (c) parallel to the discontinuous edge shall be the total width of the capital 
or brackets. If such columns are without brackets the value of (c) parallel 
to the discontinuous edge shall be taken as the width of the column plus 
twice the difference between the depth of the marginal beam, if any, and the 
depth of the slab. 

(1) Dropped panels at wall columns may be omitted, provided the allowed 
unit stresses are not exceeded. 

(m) The provisions of section twenty-six hundred and fifty-nine shall 
apply to wall panels. 

Sect. 2666. Marginal Beams in Flat Slabs. — (a) In panels having 
a marginal beam on one edge or on each of two adjacent edges, whether or 
not the slab is there discontinuous, the beam shall be designed to carry at 
least the load superimposed directly upon it, exclusive of the panel load. 
A marginal beam which has a depth greater than one and one half times the 
slab thickness, shall be designed to support, in addition to the load super- 

(215) 



Sees. 2266=2669 

imposed directly upon it, a uniformly distributed load equal to at least one 
fourth the total live and dead load for which the adjacent panel or panels are 
designed. 

(b) Where there is a beam or a bearing wall at the center line of columns 
in the interior portion of a continuous flat slab, the negative moment at the 
beam or wall line in the middle strip perpendicular to the beam or wall shall 
be taken as thirty per cent greater than the negative moment specified in 
section twenty-six hundred and fifty-seven or section twenty-six hundred 
and sixty-five for a middle strip. The half column strip adjacent and parallel 
to and lying on either side of the beam or wall shall be designed to resist 
moments, at least one fourth of those specified in section twenty-six hundred 
and fifty-seven or section twenty-six hundred and sixty-five for a column 
strip. The beam or wall in such cases shall be designed to carry a uniformly 
distributed load equal to one fourth of the panel loads on both sides in addition 
to the loads directly imposed upon it. 

Sect. 2667. Openings in Flat Slabs. — (a) Openings of any size may 
be formed in the area common to two intersecting middle strips, provided the 
total positive and total negative moments as specified in section twenty-six 
hundred and fifty-seven or section twenty-six hundred and sixty-five are 
effectually resisted when these total positive and total negative moments are 
redistributed between the remaining principal design sections to meet the 
conditions. 

(b) In an area common to two column strips, not more than one opening 
shall be allowed and the greatest dimension of such an opening shall not 
exceed (0.05L). 

(c) In an area common to one column strip and one middle strip, openings 
shall not interrupt more than one quarter of the bars in either strip when 
evenly spaced and the equivalent of the bars so interrupted shall be provided 
by extra reinforcement on both sides of the opening. 

(d) An opening larger than allowed by this section shall be completely 
framed with beams to carry the loads to the columns. 

*Sect. 2668. Construction Joints in Flat Slabs. — Construction 
joints in flat slabs shall occur preferably midway between columns. Where 
such joints occur, steel reinforcing shall be provided perpendicular to the 
joints in addition to the reinforcement required for bending of cross-sectional 
area equal to one third that required for bending at the joint. Steel rods so 
provided shall be spaced not over two times the slab thickness, shall be fully 
anchored for the allowed tensile stress by embedment each side of the joint, 
and shall be placed in the same plane with the reinforcement provided for 
bending in each strip. 

[ *As amended by Ord. 1943, ch. 8 ] 

fSect. 2669. Limiting Dimensions of Concrete Columns. — (a) 

Unless designed as long columns under the provision of section twenty-six 
hundred and seventy-three, reinforced concrete columns shall not be longer 
than ten times the least lateral dimension. Struts shall be designed as 
columns. 

(216) 



Sees. 2669-2671 

(b) In flat slab construction, except as otherwise provided in paragraph 
(c) of section twenty-six hundred and fifty-seven and paragraph (d) of section 
twenty-six hundred and sixty-five, the least dimension of a column supporting 
a floor shall be not less than one fifteenth the average center to center spacing 
nor less than sixteen inches; and that of a column supporting only a roof not 
less than one twentieth the average spacing nor less than fourteen inches. 
[ \As amended by Ord. 1943, ch. 8 ] 

Sect. 2670. Unsupported Length of Concrete Columns. — (a) The 

unsupported length of a column shall be taken as the clear distance between 
lateral supports. When the lateral support consists of a floor or roof with 
beams of different depths, the height of the column to the bottom of the 
deepest beam in a given direction shall be used with the thickness of the 
column in that direction in computing the slenderness ratio. When free- 
standing ties or struts are provided for lateral support, they shall be adequate 
to prevent the column from bending, and the clear distance between supports 
in any direction shall be used with the thickness of the column in that direc- 
tion in computing the slenderness ratio. 

(b) Concrete column capitals in flat slab construction, and brackets the 
full width of supported beams which are inclined at least forty-five degrees 
to the column, may be considered lateral supports. 

{Sect. 2671. Design of Spirally Reinforced Concrete Columns. — 

(a) The maximum allowable axial load, P, on columns reinforced with 
longitudinal bars and closely spaced spirals enclosing a circular core shall not 
exceed P = 0.225 f' c A g + A s f s . See section 2602 for symbols. 

(b) The normal working stress in the vertical column reinforcement, f 8 , 
shall be taken at 40% of the minimum specification value of the yield point; 
viz. 16,000 lbs. per sq. in. for intermediate grade steel and 20,000 per sq. in. 
for hard grade or rail steel. This reinforcement shall consist of at least six 
bars and the minimum diameter of the bars shall be five-eighths inch and 
not less than one per cent nor more than eight per cent of the gross concrete 
area. 

(c) Where lapped splices are required in the longitudinal reinforcement, 
the minimum amount of lap for deformed bars, where the strength of the 
concrete is 3000 lbs. per square inch or above, shall be twenty-four diameters 
of bar of intermediate grade steel and thirty diameters of bar of hard grade 
steel. For bars of higher yield point, the amount of lap shall be increased 
in proportion to the normal working stress. When the concrete strengths 
are less than 3000 lbs. per square inch the amount of lap shall be one-third 
greater than the values given in this paragraph. 

The lapped splices of plain bars shall be at least 25% greater than that 
given above for deformed bars. 

Welded splices or other positive connections may be used instead of lapped 
splices, if approved. 

(217) 



Sees. 2671=2672 

(d) Spiral reinforcement shall consist of evenly spaced continuous spirals 
held firmly in place and true to line by at least three vertical spacer bars. 
The outside diameter of spirals shall be maintained constant and the ends of 
the spiral wire shall be anchored. Spiral wire may be spliced by lapping one 
third the circumference of the spiral and hooking the ends, or by welding. 
The spacing of the spirals shall not exceed one sixth the diameter of the 
core nor three inches. The ratio of spiral reinforcement, p', shall not be 
less than 

/Ag \ f'e 

p' = 0.45 I 1 1 — 

\A C / f' B 

where p' is the ratio of volume of spiral reinforcement to the volume of the 
concrete core (out to out of spirals). 

A g 

— is ratio of gross area to core area of column. 
A c 

* s is useful limit stress of spiral reinforcement to be taken as 40,000 lbs. 
per square inch for hot rolled of intermediate grade, 50,000 lbs. per square 
inch for hard grade and 60,000 lbs. for cold drawn wire. 

(e) Spiral and longitudinal reinforcement shall be protected by a covering 
of concrete cast monolithic with the core not less than one and one half 
inches thick. 

(f) In columns supporting a beam-and-slab floor or roof, the spiral rein- 
forcement shall extend from the floor below at least to one and one half inches 
above the bottom of the lowest beam of the floor or roof above, which frames 
into the column. 

(g) In columns supporting a flat slab floor or roof the spiral reinforcement 

shall extend from the floor at least to mid-height of the concrete column 

capital above. 

[ %As amended by Ord. 1943, ch. 8 ] 

*Sect. 2672. Design of Tied Reinforced Concrete Columns. — (a) 

The maximum allowable axial load, P, on columns reinforced with longitu- 
dinal bars and separate lateral ties shall not exceed 
P = 0.18f' c A g + 0.8A 3 f s 

See section 2671 (b) for value of f s . 

(b) The minimum ratio of longitudinal reinforcement shall not be less 
than one per cent nor more than four per cent of the gross concrete area, 
also at least four bars shall be used, of minimum diameter of five eighths 
inch. Clear distance of the face of each bar to the face of the column shall 
be one and one-half inches plus the thickness of the column tie. Corner 
rods in columns shall not be nearer to either adjacent surface than two inches 
plus the thickness of the column tie. 

(c) Lateral ties shall be at least one quarter inch in diameter. They 
shall be spaced not more than twelve inches apart. In columns of rec- 
tangular section, containing more than four longitudinal bars cross ties shall 
be arranged to afford support to all bars. 

[ *As amended by Ord. 1943, ch. 8 J 

(218) 



Sees. 2673=2675 

*Sect. 2673. Long Columns. — (a) The axial load on columns which 
are longer than ten times the least dimension shall not be greater than — 

h 
P' = P (1.3-0.03- ) 
d' 

(b) The maximum allowable load P' on eccentrically loaded columns in 
h 
which - exceeds 10 is given by the formula in paragraph (a) in which P is 
d' 

the allowable eccentrically applied load on the short column. In long columns 
subjected to definite bending stresses, as determined by Sections 2674, 2675, 
2676, the ratio shall not exceed 20. 

[ *As amended by Ord. 1943, ch. 8 } 

fSection 2674. Bending in Concrete Columns. — (a) The bending 
moments in the columns of all reinforced concrete structures shall be deter- 
mined on the basis of loading conditions and restraint and shall be provided 
for in the design. When the stiffness and strength of the columns are utilized 
to reduce the moments in beams, girders and slabs, as in the case of rigid 
frames, or in other forms of continuous construction wherein column moments 
are unavoidable, they shall be provided for in the design. In building frames, 
particular attention shall be given to the effect of unbalanced floor loads on 
both exterior and interior columns and of eccentric loading due to other cases. 
Wall columns shall be designed to resist moments produced by 

1. Loads on all floors of the building. 

2. Loads on a single exterior bay at two adjacent floor levels, or 

3. Loads on a single exterior bay at one floor level." 

(b) Resistance to bending moments at any floor level shall be provided by 

distributing the moment between the columns immediately above and below 

the given floor in proportion to their relative stiffness and condition of restraint. 

At the roof the moments shall be provided for in the section of the column 

below. 

[ fAs amended by Ord. 1943, ch. 8 ] 

|Sect. 2675. Combined Axial and Bending Stresses. — (a) In rein- 
forced concrete columns subjected to bending stresses, recognized methods of 
analysis shall be followed in calculating the stresses due to combined axial 
load and bending. The maximum fiber stress in compression and in the case 
of large eccentricities of loading the tensile stresses in the vertical bars, as given 
in this Part will govern the design. 

(b) For designs where the eccentricity is less than 1/2 the overall 
column width, and the value of p g n is 0.3 or more, the following formula shall 
be used to calculate the combined fiber stress in compression. 



f c = 



A E 1 + (n-1) p g 
(219) 



Sees. 2675=2676 

where e is the eccentricity of resultant load, measured from the gravity axis.. 
c' is the distance from the gravity axis to the extreme fiber in com- 
pression. 
R is the radius of gyration of the equivalent concrete section, 
n is as given in section 2629. 
t' is the overall depth of the section. 
The other symbols are as given in section 2602, paragraph (b). 

ec' 6e 

The term — mav be replaced by the value — for rectangular columns and 

R 2 t' 

8e 

— for round columns, 
t' 

(c) For other limitations than mentioned in paragraph (b) more accurate 

methods of design shall be used to insure that the allowable stresses are not 

exceeded. 

[ %As amended by Ord. 1943. ch. 8] 

*Sect. 2676. Allowable Combined Axial and Bending Stresses. — 

(a) For spiral and tied columns, eccentrically loaded or otherwise subjected 
to combined axial compression and flexural stress, the maximum allowable 
compressive fiber stress shall not exceed f c in 



1 + - 

r R 2 



fe = fa- 

i + cg 

where f a is the average allowable stress on an equivalent axially loaded con- 
crete column. 
C is the ratio of f a to the allowable fiber stress for members in flexure; 
This 

0.225 f' c + f 3 p g 

f a = for spiral columns. 

1 + (n-1) p g 



[0.225 f' c + f 8 p g 1 
1 + (n-1) p g J 



f a = 0.8 | I for tied columns. 

g J 

fa 

c = 



0.45 f'c 



(b) The allowable tensile stress in the longitudinal reinforcement shall 
equal that specified for flexural members, provided however that splices 
in the tensile steel at or near the section of maximum column moment are 
capable of developing fully the yield point strength of the reinforcement. 

(c) When columns are subjected to wind stresses in addition to combined 
axial loads and bending, the column section need not be increased unless the 
allowable stress given in paragraph (a) of this section is exceeded by more than 

one-third. 

[ *As amended by Ord. 1948, ch. 8 J 

(220) 



Sees. 2677-2679 

*Sect. 2677. Combination Columns. — (a) The axial load on combi- 
nation columns, in which structural steel columns of rolled or built-up section 
wrapped with No. 10 gage wire spaced four inches on centers or its equivalent 
are encased in concrete not less than two inches thick over all of the metal, 
except rivet heads and connections, shall not exceed 



P = A r f r 



f'+— 1 

L 100A r J 



where A c is the total area of the concrete = A g -A r 

A r is the cross-sectional area of the steel column 

f ' t is the allowable stress for unencased steel column, as allowed in 
Part 28. 

(b) The concrete shall be at least equal in quality to two thousand pound 
concrete as specified in section twenty-six hundred and ten. 

(c) Stress allowed in paragraph (a) shall be allowed in compression 
members of trusses, if the requirements of this section are fulfilled. 

[ *As amended by Ord. 1943, ch. 8 ] 

fSect. 2678. Concrete Walls. — (a) Reinforced concrete walls shall 
have at least the thickness specified in Part 14. Reinforced concrete walls 
shall be reinforced in two directions at right angles by steel reinforcement 
having an effective area in each direction of not less than (0.0025) times the 
cross-sectional area of the concrete. In walls less than six inches thick the 
reinforcement may be placed at mid-thickness of the wall unless calculated 
bending requires it to be placed near one face. In walls six inches or more in 
thickness, not less than half the steel required by this paragraph shall be 
placed as close to each face of the wall as requirements for fire and rust pro- 
tection will allow. Such steel reinforcement shall be in the form of reinforcing 
bars not less than three-eighths inch in diameter and spaced not over eighteen 
inches apart or of approved wire mesh. 

(b) Protective covering for reinforcing shall be as required in section 
2627 and Part 22, except as provided in paragraph (a). 

(c) Provide construction joints and expansion joints for walls, copings 
and balustrades, together with drainage and weep holes as required by the 
commissioner. 

(d) The capacity of a reinforced concrete wall to support a vertical load 
shall be computed in the same manner as specified in sections twenty-six 
hundred and seventy-two, twenty-six hundred and seventy-three, and twenty- 
six hundred and seventy-four for columns with lateral ties. The vertical 
reinforcement shall not be assumed to contribute to the capacity of the wall 
unless it conforms to the requirements for longitudinal reinforcement in 
columns and is stayed by lateral ties perpendicular to the wall. 

[ fAs amended by Ord. 1948, ch. 8 ] 

JSect. 2679. Sloped or Stepped Concrete Footings. — (a) Footings 
shall be designed to sustain the applied loads without exceeding the allowable 
working stresses in this part. Allowable bond stress shall be reduced 25% 
from the stresses allowed in section 2629 in all tension regions requiring 
moment reinforcement in more than one direction. 

(b) Footings may have sloped or stepped tops provided the thickness of 
the footing above the reinforcement shall not be less than six inches for footings 

(22U 



Sees. 2679=2680 

on soil, nor less than nine inches for footings on piles, also plain concrete 
footings may have sloped or stepped tops provided the thickness is not less 
than twelve inches. 

(c) Concrete in reinforced footings shall be proportioned for a strength 
of at least eighteen hundred pounds per square inch. 
[ %As amended by Ord. 1943, ch. S } 

*Sect. 2680. Bending in Concrete Footings. (Critical Sections.) — 

(a) The critical section for bending in a concrete footing which supports a 
concrete column or pedestal, shall be considered to be at the face of the column 
or pedestal. Where a steel or cast iron column base rests on a concrete 
footing, moments in the footing shall be considered at the middle and at the 
edge of the base and the larger one shall be used in the design. Loads shall 
be considered as uniformly distributed over the column. In the case of 
columns other than square or rectangular the critical section shall be taken 
at the side of a concentric square of equal area. For concrete footings under 
masonry walls, moments in the footing shall be taken midway between the 
middle and the edge of the wall. 

(b) The bending moment at a critical section shall be computed from all 
the forces acting on the footing on one side of the section (excluding the weight 
of the footing). Critical sections for bond and shear shall be taken for the 
same loading and same plane as for bending. Bonds shall also be investigated 
at planes where changes in concrete section or reinforcement occur. The 
critical section for diagonal tension in footings on soil shall be considered as the 
concentric vertical section through the footing at a distance d from each face 
of the column pedestal or wall. This depth d should be measured from the 
top of the section to the plane of the centroid of longitudinal reinforcement. 
The critical section for diagonal tension for footing supported on piles should 
be considered as the concentric vertical section through the footing at a 

d 
distance — from each face of the column, pedestal or wall, and any piles 

2 
whose centers are at, or outside this section should be included in computing 
the shear. 

(c) Shear in footings shall be computed as specified in section 2642. 

(d) For reinforced concrete columns, the critical section for transverse 
bending should be taken at the faces of the columns or pedestals. For footings 
under metallic column bases, the critical section should be assumed midway 
between the face of the column and the edge of the metallic base. The trans- 
verse reinforcement should be divided into groups proportionate in sectional 
area to the column loads. The transverse reinforcement at each column 
should be placed uniformly within a band having a width not greater than the 
width of the column plus twice the effective depth of the footing. Longi- 
tudinal reinforcement should be distributed over the whole width. 

The critical sections for diagonal tension in combined footings should be 
taken at the faces of the supported members for all beam elements and also 
for all projecting cantilevers. 

[ *As amended by Ord. 1948, ch. 8 ] 

(222) 



Sees. 2681=2683 

*Sect. 2681. Plain Concrete Footings.— (a) The critical section of 
plain concrete footings shall be computed and cast as a monolithic section of the 
entire width and depth measured from a plane two inches above the bottom 
of the footing. The maximum tensile fiber stress in the concrete shall not 
exceed 0.025 of the ultimate compression strength of the concrete. The 
average shearing stress shall not exceed 0.02 of the ultimate compressive 
strength of the concrete, computed on a concentric vertical section through the 
footing at a distance (d'-2) inches from each face of the column, pedestal or 
wall, excluding two inches of depth nearest the bottom. 

(b) The area of the top of the footing shall not be less than the amoun t 
given by formula section 2682. 

[ *As amended by Ord. 1943, ch. 8 ] 

fSect. 2682. Bearing on Concrete Footing. — (a) The compressive 
stress in the longitudinal reinforcement at the base of a reinforced concrete 
column shall be transferred to a pedestal or to a footing by extending the bars 
into the pedestal or footing or by use of dowels. There shall be at least one 
dowel for each column bar, and the total sectional area of the dowels shall be 
not less than the sectional area of the longitudinal reinforcement in the column. 
The dowels or column bars shall extend into the column and into the pedestal 
or footing the distance required to transfer to the concrete, by allowable bond 
stress, their full working strength. Hooks shall not be considered as adding 
to bond resistance in compression. The unit compressive stress on the top 
of the pedestal or footing directly under the column or base shall not be 
greater than that determined by the formula 

V 



16 



Kl 



nor greater, than (0.375 f' c ) unless the pier pedestal or footing is reinforced 
laterally as provided in paragraph (b). 

(b) When lateral reinforcement in the form of a spiral or hoops is provided 
in the pedestal or footing the unit stress in bearing for the core area may be 
increased to (1 -f- 2.5 np') times that allowed for plain concrete, but no area 
outside the outer face of the spiral or hoops shall be considered. 
[ \As amended by Ord. 1943, ch. 8 } 

{Sect. 2683. Pedestals — ■ Plain Concrete. — (a) The compressive 
unit stress on the gross area of a concentrically loaded pedestal or the upper 
surface of a pedestal footing shall not exceed 0.25 f' c . 

(b) The depth and width of a pedestal or pedestal footing shall be deter- 
mined by consideration of shear and bending stresses as given in section 
2681. However, in no case shall the depth be greater than three times its 
least width. 

(c) A pedestal or pedestal footing supported directly on piles shall have a 
mat of reinforcing, of cross-sectional area not less than 0.20 square inch per 
foot of width in each direction, placed three inches above the top of the piles. 

[ %As amended by Ord. 1943, ch. 8 ] 

(223) 



Sec. 2701 

PART 27.* 
PRECAST GYPSUM CONCRETE. 

Section 

2701 — Precast Gypsum Concrete. 

Section 2701. Precast Gypsum Concrete. — (a) Precast gypsum 
concrete units may be used for floor construction and shall be of uniform 
thickness except for rabbets at support and shall be solid; such units may be 
used for roof construction and shall be of uniform thickness, whether solid 
or hollow, or recessed on the under side. The span of precast gypsum con- 
crete shall not exceed four feet in floors and six feet in roofs except in so-called 
suspension construction in which the span for floors shall not exceed six 
feet and in roofs shall not exceed eight feet. For the purpose of this section 
any span over three feet shall be called long span. 

(b) Except as otherwise provided in paragraph (c) of this section, precast 
gypsum concrete units shall have not less than the following thicknesses : — 

(1) Solid units in roofs shall be not less than two inches thick, nor if 
long span, less than three inches thick. 

(2) Solid units in floors shall be not less than two and one half inches 
thick, nor, if long span, less than four inches thick. 

(3) Hollow units in roofs shall be not less than three inches nor the shell 
in compression less than three fourths inch thick; if long span, the units 
shall be not less than five inches thick nor the shell in compression less 
than one and three eighths inches thick. 

(4) Recessed units in roofs shall be not less than five inches thick nor 
the panel less than one and three eighths inches thick. 

(c) Precast solid reinforced gypsum concrete units not more than fifteen 
inches wide and bound on the long edges with structural or pressed sheet 
steel of approved design anchored to the units shall be not less than two inches 
thick. If the length of units is not less than one and one half times the span 
and the steel bearing on the edges is designed to interlock with adjoining 
units in the manner of tongue and groove, and if of sufficient strength to 
transmit the load on one unit to adjoining units, the end joints may be stag- 
gered at random provided they are not less than two feet apart and the con- 
struction may be designed as continuous. 

(d) Precast gypsum concrete units for floor and roof construction shall 
be reinforced and unless the shape or marking of the unit is such as to ensure 
its being placed right side up, the reinforcing shall be symmetrical so that 
the unit can support its load either side up. 

(e) Precast gypsum concrete units shall be designed in accordance with 
conditions outlined in paragraph (g) below. 

(f) Precast gypsum concrete units shall not be used structurally in floors 
or roofs until the manufacturer thereof has submitted satisfactory evidence 
of their quality and the commissioner has given his approval. Approval 
shall be conditioned upon such requirements as to design, materials, methods 
of manufacture, erection and support as the commissioner shall determine. 

(224) 



Sec. 2701 

(g) The basis of design and materials shall be consistent with the following 
requirements to qualify for approval : 

( 1 ) Precast gypsum concrete shall contain not more than three per cent 
wood chips, shavings or fibre by weight of dry materials before mixing. 

(2) Precast gypsum concrete shall have a minimum strength of one 
thousand pounds per square inch. 

(3) In designing the precast gypsum concrete the modulus of elasticity 
shall be considered as six hundred thousand pounds per square inch. 

(4) In design of structural members of reinforced gypsum concrete 
the unit stress in the concrete shall not exceed the following allowable 
values : 

Maximum unit compression in bending . 25 f g 

Axial compression or bearing . 20 f g 

Bond on plain bars or wires . 02 f g 

Bond on deformed bars or wire mesh . 04 f g 

Shear (straight rods or wires) . . 0.02 f g 

Shear (reinforcement anchored) 0.03 f g 

In this table (f g ) indicates the ultimate compressive strength of the gypsum 
concrete as approved by paragraph (f) of this section. 

Unit stress in steel reinforcement shall not exceed the values allowed in 
Part 26. 

(5) Fire protection coverage for steel reinforcement in gypsum shall be 
limited to a minimum of one-half inch in thickness. 

(6) In no case shall gypsum concrete be used for a wearing surface in 
gypsum construction. 

(7) Gypsum concrete shall not be used in floors of garages, dance halls, 
gymnasiums, armories or floors used for any other purpose where subject 
to extreme vibration, impact, or heavy, moving load concentrations. 

[ *As amended by Ord. 1943, ch. 8 ] 



(225) 



Sees. 2801=2802 



PART 28. 

STEEL AND IRON. 

Section 

2801 — Design of Steel and Iron. 

2802 — Quality of Steel and Iron. 

2803 — Allowable Stresses in Structural Steel. 

2804 — Allowable Stresses in Cast Steel. 

2805 — Allowable Stresses in Cast Iron. 

2806 — Steel Tension Members. 

2807 — Steel Columns. 

2808 — Steel Beams and Girders. 

2809 — Steel Connections and Details. 

2810 — Cast Iron Columns. 

2811 — Concrete Filled Pipe Columns. 

2812 — Stresses in Steel Due to Wind. 

2813 — Thickness of Structural Steel. 

2814 — Expansion and Contraction in Steel Frames. 

2815 — Workmanship in Steel Construction. 

2816 — Painting Steel and Iron. 

2817 — Erection of Steel. 

2818 — Steel Joists. 

2819 — Column Bases of Steel and Iron. 
[2820 — Steel Deck Floors and Roofs.] 

Section 2801. Design of Steel and Iron. — Structures of steel and 
iron shall be designed by methods admitting of rational analysis according to 
established principles of mechanics, supplemented by the assumptions herein 
specified, to support the loads and withstand the forces to which they are 
subject without exceeding the stresses allowed in this part for the various 
members and the materials thereof. 

*Sect. 2802. Quality of Steel and Iron.'— 3(a) The materials of steel 
and iron construction shall conform to the specifications of the American 
Society for Testing Materials as follows: — 

(1) Structural steel to Standard Specifications for Steel for Bridges 
and Buildings. 

(2) Rivet steel to Standard Specifications for Structural Rivet Steel. 

(3) Cast steel to Specifications for Carbon Steel Castings. 

(4) Cast Iron to Specifications for Gray Iron Castings. 

(b) Special steels, alloys, high carbon steel and other metals may be used 
jn connection with steel and iron construction with the approval of the com- 
missioner and subject to such conditions as he shall specify. 

(c) Structural steel members installed in pre-code buildings prior to the 
year 1924 shall not be stressed in excess of eight-tenths of the allowable 
stresses specified in this part. Similar members installed after 1924 and prior 
to the year 1943 shall not be stressed in excess of nine-tenths of the allowable 
stresses specified in this part. 

(d) Structural steel which has previously been used in a building or other 

(226) 



Sees. 2802=2803 

structure or which has been fabricated for such use, shall not be used in 
another building or structure except with the approval of the commissioner 
and under such conditions as he may in each case specify. Holes in second- 
hand material shall not be filled in such manner as will tend to hide their 
existence, and such filling, if discovered, shall justify the commissioner in 
refusing to allow the use of the material. 

(e) The commissioner may require reasonable tests from time to time of 
steel and iron to determine its quality and whether it conforms to the require- 
ments of this chapter. 

[ *As amended by Ord. 1943 ch. 8 ] 

fSect. 2803. Allowable Stresses in Structural Steel. — (a) The unit 
stress in members of rolled structural steel, except the stress due to wind, 
shall not exceed the following allowable stresses, in pounds per square inch: — 

(1) Tension, on net section 20,000 

(2) Compression, in short members where lateral deflection is 
prevented 20,000 

(3) Compression in columns and compression members axially 
loaded; on the gross cross section: 

L 

where values of ~ is not greater than 120 for main 

r L 2 

members 17,000 — 0.485 — 

r* 
L 
and values of ~ greater than 120 but not over 200 
r 

for secondary members 18,000 

L 2 
1 + 



18,000 r 2 



where L is the unbraced length of the member and r 
is the corresponding radius of gyration of the section 
both in inches. 

(4) Bending, maximum stress on the net section : 
where lateral deflection is prevented or where L is not 

b 
more than 15 20,000 

L 

and values ~ is greater than 15, but not greater than 40 
b 

with maximum at 20,000 # 22,500 



1 + 



L 2 



where L is the unbraced length of the compression 
flange, and b is the width of the compression flange 
both in inches. 

(227) 



1,800 b s 



Sees. 2803-2804 

(5) Shear, on the gross area of the webs of beams 
and girders: 

h 

where - is not more than 60 13,000 

t 
h 

and where - is greater than 60 18,000 

t 

h 2 
1 + 



7,200 t 2 

where h is the height of the web in the clear between flanges or length in 
the clear between stiffeners, whichever is the lesser dimension, and t is the 
thickness of the web both in inches. 

(b) The bearing stress in members of rolled structural steel on pins, rivets 
and bolts with which they are connected, except the stress due to wind, shall 
not exceed the following allowable values in pounds per square inch: — 

Bearing. Double Shear. Single Shear. 

Rivets, power-driven . . 40,000 32,000 

Turned bolts in reamed or drilled holes 40,000 32,000 

Unfinished bolts and hand-driven rivets 25,000 20,000 

Pins 32,000 



(c) The unit stress in pins, rivets and bolts with which rolled structural 
steel members are connected, except the stress due to wind, shall not exceed 
the following allowable stresses in pounds per square inch: — 

(1) Shear: 

Pins . . . . . 15,000 

Rivets, power-driven 15,000 

Turned bolts in reamed holes 15,000 

Rivets, hand-driven 10,000 

Unfinished bolts . . . . . . . . . 10,000 

(2) Tension: 

Rivets . 15,000 

Bolts and threaded rods on area at root of thread . . 16,000 

(3) Bending in pins 30,000 

(d) The bearing on expansion rollers in pounds per linear inch shall not 
exceed six hundred times the diameter in inches of the roller. 

[ ]As amended by Ord. 1943, ch. 8 ] 

Sect. 2804. Allowable Stresses in Cast Steel. — The unit tension, 
compression and shear in cast steel, except the stress due to wind, shall not 
exceed sixteen thousand pounds per square inch. 

(228) 



Sees. 2805=2807 

Sect. 2805. Allowable Stresses in Cast Iron. — The unit stress in cast 
iron, except that due to wind, shall not exceed the following allowable stresses 
in pounds per square inch: — ■ 

(1) Tension . . ■ . 3,000 

(2) Compression 10,000 

(3) Compression in columns axially loaded . . 9,000 — 40 L 

r 

in which (L) is the unbraced length 

(r) is the corresponding least radius of gyra- 
tion of the column section. 

(4) Bending: 

In tension flange 3,000 

In compression flange 10,000 

Sect. 2806. Steel Tension Members. — (a) Structural steel members 
and their connections, subject to reversal of tension and compression due to 
the action of live loads, shall be designed to sustain either stress with half 
the other stress added, whichever requires the larger section. If the reversal 
of stress is due to the action of wind, the member shall be designed for the 
stress requiring the larger section and the connections shall be designed for 
the larger stress. 

(b) In calculating the net section of tension members, the area of rivet 
holes shall be deducted assuming the diameter of the hole to be at least one 
eighth inch larger than the nominal size of the rivet. 

(c) Pin-connected tension members shall have an area of cross-section 
through the pin hole at least twenty-five per cent in excess of the net area 
required in the member, and a net area of cross-section back of the pin hole 
at least equal to the net area required on one side of the pin hole. 

L 
*Sect. 2807. Steel Columns. — (a) The ratio ( — ) shall not exceed one 

r 
hundred and twenty for columns in buildings and main compression members 
in trusses and frames; nor two hundred for bracing and other secondary 
members. 

(b) In structural steel columns and compression members of trusses, 
subject to eccentric loads or to bending other than that incidental to axial 
loading, the maximum unit compression shall not exceed twenty thousand 
pounds per square inch — 

(1) When calculated by a method which takes full account of deflection 
and buckling in any direction; or, — 

(2) When the applied bending is in the plane of a principal axis and the 
stress is calculated by the following formula: — 

P L 2 Mc 

- (1 + ) + 

A 18,000 r 2 P S 2 

I 

10 E 

(229) 



Sees. 2807=2808 

in which (M) is the applied bending. 

(S) is the length of column unbraced in the plane of the bending. 
(I) is the moment of inertia about a center of gravity axis per- 
pendicular to the plane of the bending, 
(c) is the distance from that axis to the remote fibre in compression. 

L 

(■ — ) is the slenderness ratio at right angles to the plane of the applied 
r bending. 

(E) is the modulus of elasticit}^ of steel. 

[ *As amended by Ord. 1943, ch. 8 ] 

fSect. 2808. Steel Beams and Girders. — (a) In rolled steel beams 

Li 

and girders, whether of solid section or built up, the ratio ( — ) shall not 

b 
exceed forty. 

(b) The compression flanges of beams, girders, lintels and similar members 
in bending shall in general be braced laterally, by the floor or roof construc- 
tion or framing, or by struts or tie rods. Steel joists, floor slabs or other 
construction, to be considered effective bracing shall have positive connection 
to the beam or girder and friction shall not be relied upon. Standard dia- 
phragm separators, joining two members in bending, or steel pipe separators 
with concrete filling, shall be considered effective lateral support to each of 
the members. 

(c) The span of beams and girders shall be taken as the distance from 
center to center of bearings. If a beam or girder is connected to the face of a 
flange or web of a column, the span shall be taken to such face. 

(d) In calculations for stress due to bending in built up beams and girders, 
and in rolled sections with punched flanges, the moment of inertia and section 
modulus of net sections shall be used. 

(e) Where beams or girders are composed of two or more I-beams or 
channels, they shall be so connected as properly to distribute the load to each 
member. 

(f) Beams, girders, and trusses of steel shall be so designed that the 
deflection under load shall not exceed one three hundred and sixtieth of the 
span. The modulus of elasticity of rolled steel shall be taken as twenty-nine 
million pounds per square inch. 

(g) Beams and girders subject to the thrust of floor arches, purlins or 
inclined roofs, crane runway girders and other members subject to bending 
in more than one plane shall be so designed that the maximum unit stress 
due to combined loading shall not exceed the stress allowed in this chapter, 
except as provided in section twenty-eight hundred and twelve. Eccentric 
loads shall be provided for. 

(h) Beams which are wholly encased, as required for fireproofing, in the 
concrete of a reinforced concrete floor or roof may be designed for bending as 
composite beams, as provided in Part 26. 

(i) Plate girder webs shall have a thickness not less than one one hundred 
and sixtieth of the clear distance between flanges, nor less than one fourth 
inch. 

(230) 



Sees, 2808=2809 

(j) Web splices shall have at least one plate on each side of the web 
riveted thereto in such manner that the shear is transmitted; and bending, 
if the web is designed to resist bending. 

(k) Stiffeners shall be provided on both sides of the webs of plate girders 
over end bearings and where necessary at points of concentrated loads, 
designed to transmit the reactions and loads to the web. Bearing stiffeners 
shall not be crimped over flange angles, and shall be fitted to the flange angles 
where they bear. Where the ends of stiffener angles are chamfered to clear 
the fillets of flange angles, the outstanding legs only shall be computed in 
bearing and the average unit stress in bearing shall not exceed twenty-seven 
thousand pounds per square inch. Where stiffener angles are raised from the 
web on fillers to clear the fillets of flange angles and the whole of the stiffener 
angle is fitted in bearing, the average unit stress shall not exceed eighteen 
thousand pounds per square inch. 

(1) Fitted stiffeners shall also be provided on the webs of rolled I-beams 
and channels where necessary to transmit to the web the end reactions or con- 
centrated loads. 

(m) Intermediate stiffeners shall be provided on both sides of the webs 

of plate girders where the thickness of the web is less than one sixtieth of 

the clear distance between flanges. Clear spacing between stiffeners shall 

not exceed 84 inches nor be more than 

3_ 
270,000 t V vt 

V h 

where h is the clear depth between flanges, in inches 

t is the thickness of the web, in inches 

v is the greatest unit shear in panel, in pounds per square inch under any 

condition of complete or partial loading. 
Plate girder stiffeners shall be in pairs, one on each side of the web, and shall 
be connected to the web by rivets spaced not more than 8 times their normal 
diameter. 

Stiffeners as indicated above in this paragraph need not be provided where 
adequate provision is made against buckling and torsion. Intermediate 
stiffeners shall overlap but need not bear on flange angles. 
[ fAs amended by Ord. 1943, ch. 8 ] 

JSect. 2809. Steel Connections and Details. — (a) Rivets driven 
in the field or shop by approved pneumatic hammers shall be considered 
power-driven rivets. Turned bolts shall have a clearance in reamed holes 
not more than one fiftieth inch; holes shall be reamed after assembly of the 
members connected. The finished shank of turned bolts shall be long enough 
to provide full bearing, with washers under the nuts to permit tight gripping 
of members when turned up, and nuts shall be locked. 

(b) Riveted joints shall be designed to transmit the entire stress through 
the rivets, except as otherwise provided in paragraph (c). 

(c) Joints in compression members shall be fully spliced, except that 
where reversal of stress is not possible and the joint is supported laterally, 
the ends of the members may be milled to plane parallel surfaces and abutted, 
with sufficient splicing to hold the connected members accurately and firmly 
in place and in bearing. 

(231) 



Sec. 2809 

(d) Riveted connections transmitting calculated stress, except in lacing 
and sag bars, shall have not less than two rivets. 

(e) Members in tension or compression meeting at a joint shall have 
their lines of center of gravity pass through a point, if practicable; and if 
not, provision shall be made for the eccentricity. 

(f ) A group of rivets transmitting stress to a member shall have its center 
of gravity in the line of stress if practicable; and if not, the group shall be 
designed for the resulting eccentricity. 

(g) When a beam or girder is connected by a connection more rigid than 
a standard web connection, to a supporting member in such a way that it acts 
as continuous or fixed at the end, proper provision shall be made for the 
bending at the connection. 

(h) When stress is transmitted from one member to another by rivets 
through a filler, the number of rivets shall be increased thirty per cent over 
the number required for connecting members in contact. The additional 
rivets so provided may be used to produce a tight filler. 

(i) In designing riveted or bolted connections, the nominal diameter of 
the rivet or bolt shall be used. 

(j) Rivets transmitting calculated stress, when the grip exceeds five 
diameters, shall have their number increased one per cent for each additional 
one-sixteenth inch in rivet grip. 

(k) The required strength of riveted connections shall be developed by 
the shearing and bearing values of the rivets, but rivets in shelf angles or 
bracket supports, and in connections in so far as they also afford rigidity 
to the structure, may transmit stress by tension. 

(1) The rivet pitch in the line of stress in compression members shall not 
exceed sixteen times the thickness of the thinnest outside plate or shape nor 
twenty times the thickness of the thinnest inclosed plate or shape, nor in 
any case more than twelve inches. At right angles to the direction of stress 
the distance between lines of rivets shall not exceed thirty times the thinnest 
plate or shape. 

(m) In built up sections with angles having two gage lines with rivets 
staggered, the rivet pitch in the line of stress in each gage line shall not exceed 
twenty-four times the thickness of the thinnest plate or shape, nor eighteen 
inches. 

(n) In built up sections the distance from the center of rivet holes to an 
edge shall not exceed twelve times the thickness of the thinnest plate or shape 
nor six inches. 

(o) The provisions of this section for riveted connections shall also apply, 
where pertinent, to bolted connections. 

(p) Rivets or turned bolts shall be used for either shop or field work in 
the fabrication and erection of primary members, members carrying loads 
which produce impact or vibration and in connections subject to reversal of 
stress, except as otherwise provided in paragraphs (q) and (r). 

(q) Unfinished bolts may be used for primary and secondary field con- 
nections in buildings other than Type I and Type II, in buildings of Type I 

(232) 



Sees. 2809=2810 

and Type II less than ten thousand square feet in total floor area, and in 
the connections to cast iron or filled pipe columns, connections of secondary 
members in all structures, such as purlins, girts, door and window framing, 
alignment bracing, and secondary beams in floors and roofs. 

(r) Arc and gas welding may be employed as a substitute for or in com- 
bination with riveting, bolting or other connecting means permitted under 
this code, for connecting to one another or assembling the component parts 
of structural steel of buildings, or for connecting steel to wrought iron members 
of pre-code buildings, provided that such work be designed and executed in 
accordance with the American Welding Society Code for Arc and Gas Welding 
in Building Construction, latest edition, and modified as follows: 

1. The ability of welding operators to produce welded connections of 
the required strength shall be determined by having them prepare strength 
test specimens. 

2. The preparation of these specimens and strengths required shall be 
as determined by the commissioner, but such strengths shall not be less 
than those prescribed in the American Welding Society Code for Fusion 
Welding and Gas Cutting in Building Construction, Part 2, Structural Steel. 

3. The building Commissioner shall promulgate rules and regulations 
as to operation and inspection of welding, and the qualifications of welders, 
(s) Qas Cutting: 

Gas cutting may be substituted for shearing, sawing or other cutting 
means, in fabricating or altering structural steel or wrought iron members 
of buildings subject to the following limitations: 

1. Gas cutting shall be done by experienced and competent workmen. 

2. Gas cut edges shall be reasonably smooth and regular. 

3. Gas cutting may be used in preparing base-metal parts for welding, 
provided that the edges so cut be thoroughly cleaned so as to expose a 
clean surface. 

4. Gas cutting shall not be used to replace milling for bearing surfaces. 

5. Gas cutting shall not be performed on a member while under stress. 

6. Gas cutting of members to form openings or to remove portion of 
flanges shall not be done unless the design provides therefor. 

7. Gas cutting shall not be used to form rivet holes or bolt holes. 

[ %As amended by Ord. 1948, ch. 8 ] 

Sect. 2810. Cast Iron Columns. — (a) Cast iron columns shall not 
be used in the primary structural frames of buildings whose height exceeds 
one hundred feet or twice the width at the ground level. Cast iron shall not 
be used for columns required to have four-hour fire-resistive protection. 

(b) The ends of cast iron columns shall be machined to a smooth plane 
surface perpendicular to the axis to provide full bearing for the entire cross- 
section of the column. 

(c) Hollow cast iron columns, except when open at both ends and without 
flanges, shall have two three eighths inch holes drilled in the shell to exhibit 
the thickness thereof. If the columns are cast on the side, both holes shall 
be in the top side as cast, one hole about twelve inches toward each end from 
mid-length of the column. If the columns are cast on end, both holes shall 

(233) 



Sees. 2810=2811 

be at mid-height at ninety degrees from one another about the axis of the 
column. Additional holes shall be drilled when required by the commissioner- 
If the core of a cast iron column is found to have shifted more than one quarter 
the thickness of the shell, the strength shall be computed assuming the thick- 
ness all around to be that of the thinnest part. 

(d) Cast iron columns shall not be smaller than six inches in outside 
diameter or side, and the thickness of metal shall not be less than three fourths 
inch nor less than one twelfth the outside diameter or widest side. 

(e) Cast iron columns supporting a floor shall not be longer than seventy 
times the least radius of gyration or twenty-four times the outside diameter 
or least side. Cast iron columns supporting roof loads only shall not be 
longer than ninety-six times the least radius of gyration or thirty times the 
outside diameter or least side. 

(f) Cast iron columns shall not be used where the loading is so eccentric 
as to cause tension, nor shall they be used in garages or other structures where 
they may be subject to impact from vehicles. 

*Sect. 2811. Concrete Filled Pipe Columns. — (a) Steel pipes filled 
with concrete may be used as columns and under axial loads the capacity shall 
be assumed to be that of the pipe computed as provided in this chapter plus 
the capacity of the concrete. The unit stress in the concrete shall not exceed 
one-fourth the 28-day strength of the concrete as designated in Part 26- 
The ratio of L/d shall not exceed 40, where L is the unbraced height of the 
column in inches and d is the outside diameter of the pipe in inches. 

(b) Steel equal in quality to that described in Section 2802, paragraph (1) 
shall be used for pipe. Pipe shall be new and full size, shall be made by the 
seamless process or equal and for sizes larger than four inches in outside 
diameter, shall be standard weight or heavier. Pipe shall be cut square to its 
length. Ends shall be milled if necessary to obtain the exact length. 

(c) Concrete filling shall be machine-mixed and proportioned for a strength 
of not less than three thousand pounds per square inch, as described in Part 26. 
Concrete shall be compacted by a satisfactory mechanical method while being 
placed. 

(d) Where required to increase the strength of columns, longitudinal steel 
reinforcement may be used. Reinforcement shall be new, straight, con- 
tinuous for the entire length of the column, symmetrically placed and ends 
milled for bearing, and ends arranged for even bearing with the pipe and 
milled after filling if necessary to obtain uniform bearing. The strength of 
this reinforcement shall be calculated by adding its net area to the area of the 
steel pipe in paragraph (a) and using the net area of concrete. 

(e) Bases, caps, web ties and brackets shall be of steel. Each shall be 
attached by an approved method. Brackets and web ties shall have a 
mechanical anchorage in addition to welding. Welding and cutting shall be 
done in accordance with requirements of section 2809, paragraphs (r) and (s) • 

(f) Material surrounding a filled pipe column for fire protection shall not 
be considered either load-bearing or as increasing the stiffness. 

(g) Filled pipe columns shall be inspected during their manufacture by an 

(234) 



Sees. 2811=2815 

inspector appointed by the commissioner. This inspector shall attach a 
permanent label to each column inspected and approved and shall file a record 
of all inspections with the commissioner. 

(h) Copies of sanction tests of filled pipe columns made according to this 
section shall be filed with the commissioner for each diameter of column 
produced by a manufacturer to be of approximate L/d of 24. Tests shall be 
made in an approved laboratory. For acceptanpe the test strength shall 
not be less than three times the working strength as computed by paragraph 
(a) hereof. 

(i) For columns without sanction tests or existing unapproved columns, 
the unit working stress shall not exceed in pounds per square inch 

for steel 10,000 

for concrete 500 

[ *As amended by Ord. 1943, ch. 8 ] 

Sect. 2812. Stresses in Steel due to Wind. — Structural steel members 
subject to stress due to wind shall be so designed that the maximum unit 
stress from all loads and forces combined shall not exceed by more than one 
third the allowable stresses specified in this chapter and the unit stress due 
to loads and forces other than wind shall not exceed the specified allowable 
stresses. 

fSect. 2813. Thickness of Structural Steel. — The thickness of metal 
in structural steel members shall not be less than five-sixteenths of an inch 
where exposed to moisture or the weather, and not less than one-quarter of an 
inch where protected from moisture and the weather. Both these require- 
ments do not apply to steel joists as defined in section 2818, members formed 
of flat rolled steel, the flange edges and webs of rolled beams, channels, stairs, 
fire escapes, signs, skylights, windows, non-bearing walls and partitions, 
suspended ceilings, cornice brackets, ventilator hoods, marquees, and other 
light iron work, and structural steel for buildings in Type V one story high, 
[ ^As amended by Ord. 1943, ch. 8 ] 

Sect. 2814. Expansion and Contraction in Steel Frames. — Proper 
provision shall be made for expansion and contraction. 

Sect. 2815. Workmanship in Steel Construction. — (a) Structural 
steel members shall be straight and true and any piece damaged to such an 
extent as to impair its strength shall not be used in the construction of a 
building. 

(b) Structural steel members shall not be cut, notched, or pierced for 
clearance of pipes, conduits, wires, ducts, or for other reasons, in such a way 
as to impair their strength unless provision therefor has been made in the 
design. 

(c) Drifting to enlarge unfair holes shall not be permitted. Rivet holes 
shall not be burned. 

(d) The several pieces forming built-up sections shall be straight and shall 

fit closely together; and finished members shall be free from twists, bends or 
open joints. 

(235) 



Sees. 2815=2817 

(e) Rolled sections shall not be heated in any manner which will impair 
their strength or quality, nor cut with the torch while under stress. A torch 
shall not be used in the field to cut structural steel except with the approval 
of the commissioner and in the presence of an inspector appointed by him. 

(f) Steel castings shall be properly annealed. 

(g) Except under such conditions as the commissioner may specify, 
rivets shall be driven at bright red heat, and wherever practicable, by power 
riveters. Rivet heads shall be of hemispherical shape, uniform in size through- 
out the work for the same size rivet, full, neatly finished and concentric with 
the holes. Rivets after driving shall be tight, completely filling the holes, 
and with heads in full contact with the gripped surfaces. 

*Sect. 2816. Painting Steel and Iron. — (a) Structural steel (except 
the parts which are to be welded, surfaces in contact, or entirely encased in 
concrete) shall be thoroughly cleaned before erection and painted one coat of 
approved paint well worked into joints and open spaces including surfaces 
which have been welded. 

(b) After erection, steel work (except that which is to be encased in con- 
crete) shall be painted an additional approved coat of another color. These 
requirements shall not apply to steel joists and other secondary members 
formed from sheet steel except that these members where embedded in 
exterior walls shall be painted from the wall to a point one foot inside the 
inside face of the exterior wall. If the shop coat of paint on steel members 
has been damaged in transit or erection, the damaged portions shall be field 
painted after erection. 

(c) Required shop painting of shop-welded work shall be applied after 
the welding is completed. Required shop painting of work to be field welded 
shall consist of a coat of linseed oil except that this shall not apply to steel 
joists and other secondary members formed from sheet steel. Required 
field painting of field-welded work shall be applied after welding is finished 
and shall consist of two coats of approved paint. 

(d) Primary frame steel built into exterior masonry walls shall have 
adequate protection against corrosion by encasing in one and one-half inches 
of Portland cement mortar, see section 2411 paragraph (h) or by a mastic 
asphalt or pitch one-eighth inches thick or its approved equivalent. Masonry 
protection herein mentioned shall not change other masonry requirements. 

(e) Welded connections and cast iron columns shall not be painted until 
after inspection and approval by the commissioner. 

[ *As amended by Ord. 1943, ch. 8 ] 

Sect. 2817. Erection of Steel. — (a) The steel frames of buildings 
or other structures shall be erected true and plumb, and temporary bracing 
shall be provided wherever necessary to support the loads to which the 
structure may be subjected, including erection equipment and its operation. 
Such bracing shall be left in place as long as required for safety. 

(b) As erection progresses, the work shall be securely bolted up to resist, 
all stresses to^which it may be subjected. 

(236) 



Sees. 2817=2818 

(c) No field riveting or welding shall be done in any portion of a structure 
until that portion has been properly plumbed and aligned. 

(d) In the setting or erecting of steel work the individual pieces shall be 
considered plumb or level when the error does not exceed one in five hundred. 
Exterior columns and columns adjacent to elevator shafts shall not be out 
of plumb in excess of one in one thousand, in the total height of the columns. 

*Sect. 2818. Steel Joists. — (a) Steel joists, for the purposes of this 
chapter, shall mean light weight rolled steel sections, welded truss assemblies 
or expanded rolled sections. They shall include — ■ 

(1) Junior Beams, so-called. 

(2) Other rolled steel beams of (I) or channel section the flanges of 
which are narrower than two inches plus one sixth the depth (except 
American standard channels) or the webs of which are thinner than seven- 
teen hundredths inch plus five thousandths of the depth. 

(3) Beams of I-section, channels or other sections fabricated by bend- 
ing, pressing, welding or expanding sheet steel. 

(4) Steel joists, so-called, consisting of trussed members of which the 
chords are made of bars or of structural shapes thinner than one quarter 
inch, or the webs are made of bars; assembled by welding or otherwise; 
or fabricated by shearing and expanding the web of rolled I-beam; or any 
similar trussed steel beam. 

(b) Steel joists shall not be more than twenty inches deep. 

(c) Steel joists shall not be used in floors of garages, dance halls, gymna- 
siums, armories, or floors used for any other purpose where subject to 
extreme vibration, impact, or heavy moving load concentrations, nor in 
floors supporting live loads in excess of one hundred twenty-five pounds per 
square foot. 

(d) The provisions of this chapter for design and materials of structural 
steel shall apply to steel joists. 

(e) Every steel joist, when erected and bridged, shall be capable of sup- 
porting safely a concentrated load of at least eight hundred pounds at any 
panel point. Welded joints of trussed joists, when tested shall be capable 
of resisting at least three times the maximum design stress. 

(f) The span of joist having an all steel top chord shall not exceed five 
hundred and fifty times the radius of gyration of the top chord in a plane 
perpendicular to the web of the joist, but in case the top chord consists of a 
flat top section continuous with a center web, the radius of gyration of the 
top plate alone shall be taken. Joist having a top chord of steel with a wood 
nailing strip attached shall be limited in span to one hundred sixty times the 
total width of the top chord. The span shall not exceed twenty-four times 
the depth of the steel portion of the joist. 

(g) Bridging shall be provided for steel joists to afford lateral support 
during erection and to distribute concentrations of live load among adjacent 
joists. Bridging shall be of approved rigid type capable of transmitting at 
least five hundred pounds to each adjacent joist and shall securely support 
the top chord or flange against lateral displacement. Such bridging shall 

(237) 



Sees. 2818=2820 

be provided at intervals not more than eight feet nor more than forty times 
the width of the top flange or chord. Unless steel joists are supported at 
the ends by web connections, built into masonry walls or otherwise supported 
laterally, they shall have bridging at the ends. 

(h) Steel joists parallel to masonry walls or to steel or concrete beams 
shall have both top and bottom chords or flanges anchored thereto in the 
line of bridging. Such anchors shall consist of flat steel not less than one 
inch by one eighth inch effectively arranged, or other equivalent approved 

anchorage. 

(i) Steel joists shall have at least four inches bearing on masonry walls 
and shall be anchored thereto by approved anchor. Steel joists supported 
on the top of steel beams shall have at least three inches bearing and shall 
extend at least one inch beyond the center line of the web. Steel joists 
depended upon for lateral support to a beam shall have positive connection 
thereto other than by friction. Steel joists shall be secured against lateral 
displacement at the ends. 

(j) Steel joists shall not be used in the first floor of a building where 
there is not a basement or cellar below, unless it has clearance above the 
ground of at least twenty-four inches, and the space below is ventilated 
either to a heated basement or to the outside air. Ventilation of such space 
to a heated basement shall consist of at least two remote openings in the 
basement wall having a total area of at least two square feet for each twenty- 
five linear feet of wall. Ventilation of such space to outside air shall consist 
of one or more openings in each exterior wall thereof, well distributed, except 
that openings need not be provided in the front wall when the space is ven- 
tilated in the rear and both side walls. The aggregate area of openings 
shall be not less than two square feet for each twenty-five linear feet of wall. 
Openings in exterior walls shall be protected by non-corrodible wire mesh 
with openings not greater than one half inch. 

[ *As amended by Ord. 1943, eh. 8 } 

Sect. 2819. Column Bases of Steel and Iron.— (a) Steel or cast 
iron bases under steel, cast iron or filled pipe columns shall be plane and 
smooth. They shall be designed on the assumption that the column bears 
uniformly upon the base, and that the base bears uniformly upon the sup- 
porting foundation, except when the column is anchored to the foundation 
to resist calculated bending. 

(b) Cast iron bases shall be planed on top and bases which rest on struc- 
tural steel members shall be planed on the bottom. The thickness of cast 
iron shall be not less than one inch. The outer edge of the ribs of ribbed 
bases shall be inclined not less steeply than forty-five degrees. A side of the 
bed plate of ribbed bases exceeding three feet in length shall have a rein- 
forcing flange at least three inches high. 

fSect. 2820. Steel Deck Floors and Roofs.— (a) This type of con- 
struction for the purposes of this Part shall mean secondary members and 
decking of steel in the form of flats or of various shapes or of combination 
with rolled steel sections. 

(238) 



Sec. 2820 

(b) The provisions of this Part for design of structural steel shall apply 
to steel deck construction. 

(c) The quality of steel shall meet the specifications of the American 
Society of Testing Materials for Light Gage Structural Quality Flat Hot- 
Rolled Carbon Steel. Stresses for design in extreme fibre shall not exceed 
18,000 lbs. per square inch. Tests shall be as described elsewhere in this Code p 

(d) Minimum U. S. gage of sheets for floors shall be 18 gage and for 
roofs 22 gage. Connections shall be made by riveting, bolting, welding 
or by other methods equally secure. Provisions shall be made to secure 
the decking against uplift, vibration and deflection. Protection shall be 
made by painting or otherwise, as provided for steel in this part. 

(e) Steel deck construction shall not be used in floors of garages, dance 
halls, gymnasiums, armories, or floors used for any other purpose where 
subject to vibration, impact or heavy moving load concentrations, nor in 
floors supporting live loads in excess of one hundred twenty-five pounds per 
square foot. 

[ fAs amended by Ord. 1948, ch. 8 ] 



cm) 



Sec. 2901 



PART 29. 
EXCAVATIONS AND FOUNDATIONS. 

Section 

2901 — Excavations. 

2902 — Depth of Foundations. 

2903 — Borings and Test Pits. 

2904 — Classification and Allowable Loads of Foundation Bearing 

Materials. 

2905 — Foundation Loads. 

2906 — Foundation Design. 

2907 — Footings, Caisson Piers and Pile Caps. 

2908 — Piles — General Requirements. 

2909 — Allowable Load on Piles. 

2910 — Wooden Piles. 

291 1 — Precast Concrete Piles. 

2912 — Cast=in=Place Concrete Piles. 

2913 — Concrete=Filled Cylindrical Steel Piles. 

2914 — Composite Piles. 

2915 — Foundation Load Tests. 

2916 — Load Tests of Bearing Materials. 

2917 — Pile Loading Tests. 

*Section 2901. Excavations. — (a) Until provision for permanent 
support has been made, excavations shall be properly guarded and protected 
by the persons causing them to be made so as to prevent such excavation 
from becoming dangerous to life or limb. Excavations shall be sheet-piled, 
braced or shored, and permanent excavations shall be protected by retaining 
walls or other permanent structures, where necessary, to prevent movement 
or caving of the adjoining soil. 

(b) Structures near an excavation and owned by another than the person 
causing the excavation to be made shall be supported as follows: — 

(1) Where an excavation is carried below the curb grade at the com- 
mon property line, or below the surface of the ground where there is no such 
curb grade, the person causing such excavation to be made shall, at all 
times, if accorded the necessary license to enter upon the adjoining land, 
and not otherwise, at his own expense, preserve and protect from injury 
any wall, building, or structure, the safety of which may be affected by 
said excavation, and shall support it by proper foundations. If the neces- 
sary license is not accorded to the person making such excavation, then it 
shall be the duty of the owner refusing to grant such license to make such 
wall, building or structure safe and to support it by proper foundations; 
and, when necessary for that purpose, such owner shall be permitted to 
enter upon the premises where such excavation is being made. 

(240) 



Sees. 2901-2903 

(2) Where a party wall is intended to be used by the person causing 
the excavation to be made, he shall, at his own expense, preserve such 
party wall from injury and shall support it so that the said party wall 
shall be safe for the purposes intended. 

(c) If the person whose duty it shall be under the provisions of this 
section to guard and protect an excavation, or to prevent adjoining soil 
from moving or caving, or to preserve or protect any wall, building, or 
structure from injury, shall neglect or fail so to do, the commissioner may 
enter upon the premises, and make safe such excavation, wall, building or 
other structure as provided in section one hundred and sixteen of Part I. 
[ *As amended bij Ord. 1943, ch. 8 ] 

fSect. 2902. Depth of Foundations.— (a) The foundations of 
every permanent structure shall be supported by satisfactory bearing ma- 
terial, which shall mean natural deposits of rock, gravel, sand, rock flour 
(inorganic silt), clay, or any combination of these which does not contain 
an appreciable amount of organic matter. 

(b) Where footings are supported at different levels, or at different levels 
from footings of adjacent structures, foundation plans shall include vertical 
sections showing to true scale all such variations in grade. The effect of 
such differences in footing levels on the bearing materials shall be considered 
in the design. 

(c) The foundations and grade beams of permanent structures, except 
when founded on rock, and except as otherwise provided in paragraph (d) of 
this section, shall be carried down at least four feet below an adjoining surface 
exposed to natural or artificial freezing. 

(d) Foundations of detached garages or similar accessory structures of 
six hundred fifty square feet or less in area and not over one story high, and 
grade beams of all structures need not be carried more than one foot below 
an adjoining surface exposed to freezing if the underlying soil to a depth of at 
least four feet beneath the surface is clean sand and gravel. No foundation 
shall be placed on frozen soil. Foundations shall not be laid in freezing 
weather unless adequately protected. 

(e) Basements or cellars which are surrounded by water-bearing soil shall 
be waterproofed up to a grade at least two feet above the maximum probable 
ground water level. Walls and floors to be so water proofed shall be designed 
to resist full hydrostatic pressure. Under boilers, furnaces and other heat- 
producing apparatus, suitable insulation shall be installed to protect the 
waterproofing against damage from heat as specified in Part 21. 

[ -\As amended by Ord. 1943, ch. 8] 

Sect. 2903. Borings and Test Pits. — (a) Before issuing a permit for 
erection or alteration of a permanent structure, the commissioner, in the 
absence of satisfactory data, shall require the owner to dig pits or make 
borings at such locations and carried to such depths as will disclose the 
character of the materials underlying the site of the proposed structure. 
When it is proposed to support a structure directly on bedrock, loading the 
rock to more than ten tons per square foot, the commissioner may require a 

(241) 



Sees. 2903-2904 

drill hole or a core boring to be made at each pier location, carried into the 
rock a sufficient depth to prove that sound bedrock has actually been reached, 
(b) Copies, in duplicate, of the results of all borings and pits made or 
started, together with samples properly protected from evaporation repre- 
senting the various classes of soil as nearly as possible in their natural state 
in the ground, including samples of the materials selected for the support of 
the foundation, shall be filed with the commissioner for his information and 
classification. Washed or bucket samples will not be accepted. 

*Sect. 2904. Classification and Allowable Loads of Foundation 
Bearing Materials. — (a) The terms used in the following classification 
shall be interpreted in accordance with generally accepted geological and 
engineering nomenclature. Certain terms shall, for the purposes of this 
chapter, have more specific interpretations, as follows: 

(1) Rocks. 

Shale; — A laminated, fine-textured, soft rock composed of consolidated 
clay or silt, which cannot be molded without the addition of water, but 
which can be reduced to a plastic condition by moderate grinding and 
mixing with water. 

Slate; — A dense, very fine-textured, soft rock which is readily split 
along cleavage planes into thin sheets and which cannot be reduced to a 
plastic condition by moderate grinding and mixing with water. 

Schist; — A fine-textured, laminated rock with a more or less wavy 
cleavage, containing mica or other flaky minerals. 

(2) Granular soil. 

Gravel; — An uncemented mixture of mineral grains one quarter inch 
or more in diameter. 

Sand; — A type of soil possessing practically no cohesion when dry, and 
consisting of mineral grains smaller than one quarter inch in diameter. 

Coarse Sand; — A sand consisting chiefly of grains which will be retained 
on a sixty-five mesh sieve. 

Fine Sand; — A sand consisting chiefly of grains which will pass a sixty- 
five mesh sieve. 

Compact Gravel, Compact Sand; — 'Deposits requiring picking for re- 
moval and offering high resistance to penetration by excavating tools. 

Loose Gravel, Loose Sand;— Deposits readily removable by shoveling 
only. 

(3) Cohesive soil. 

Hardpan; — A thoroughly compact mixture of clay, sand, gravel, and 
boulders, for example boulder clay; or a cemented mixture of sand or of 
sand and gravel, with or without boulders, and difficult to remove by pick- 
ing. 

Clay; — ■ A fine-grained, inorganic soil possessing sufficient cohesion when 
dry to form hard lumps which cannot readily be pulverized by the fingers. 

Hard Clay; — A clay requiring picking for removal, a fresh sample of 
which cannot be molded in the fingers. 

Medium Clay; — A clay which can be removed by spading, a fresh sample 
of which can be molded by a substantial pressure of the fingers. 

(242) 



Sec. 2904 

Soft Clay;—- A clay which, when freshly sampled, can be molded under 

relatively slight pressure of the fingers. 

Rock Flour (Inorganic Silt) ; — A fine-grained, inorganic soil consisting 

chiefly of grains which will pass a two hundred mesh sieve, and possessing 

sufficient cohesion when dry to form lumps which can readily be pulverized 

with the fingers. 

(b) The maximum pressure on soils under foundations shall not exceed 
the allowable bearing values set forth in the following table except when 
determined in accordance with the provisions of sections twenty-nine hundred 
and fifteen and twenty-nine hundred and sixteen, and in any case subject to 
the modifications of subsequent paragraphs of this section. 



Class. 



Material. 



Allowable Bearing 

Value (Tons per 

Square Foot). 



3 

4 

5 
6 

7 
8 
9 
10 
11 
12 
13 



Massive bedrock without laminations, such as granite, diorite, 
and other granitic rocks; and also gneiss, trap rock, felsite 
and thoroughly cemented conglomerates, such as the Rox- 
bury Puddingstone, all in sound condition (sound condition 
allows minor cracks) , 

Laminated rocks such as slate and schist, in sound condition 
(minor cracks allowed) 

Shale in sound condition (minor cracks allowed) 

Residual deposits of shattered or broken bedrock of any kind 
except shale 

Hardpan , 

Gravel, sand-gravel mixtures, compact 

Gravel, sand-gravel mixtures, loose; sand, coarse, compact 

Sand, coarse, loose; sand, fine, compact 

Sand, fine, loose 

Hard clay 

Medium clay 

Soft clay 

Rock flour, shattered shale, or any natural deposit of unusual 
character not provided for herein 



100 

35 

10 

10 

10 

5 

4 
3 

1 
6 

4 
1 



* Value to be fixed by the Commissioner. 



(c) The tabulated bearing values for rocks of Classes 1 to 3 inclusive 
shall apply where the loaded area is less than two feet below the lowest adja- 
cent surface of sound rock. Where the loaded area is more than two feet 
below such surface these values may be increased twenty per cent for each 
foot of additional depth but shall not exceed twice the tabulated values. 

(d) The allowable bearing values of materials of Classes 4 to 9 inclusive 
may exceed the tabulated values by two and one half per cent for each foot 
of depth of the loaded area below the lowest ground surface immediately 
adjacent, but shall not exceed twice the tabulated values. For areas of 

(243) 



Sees. 2904-2906 

foundations smaller than three feet in least lateral dimension, the allowable 
bearing values shall be one third of the tabulated bearing values multiplied 
by the least lateral dimension in feet. 

(e) The tabulated bearing values for Classes 10 to 12 inclusive apply 
only to pressures directly under individual footings, walls, and piers. When 
structures are founded on or are underlain by deposits of these classes, the 
total load over the area of any one bay or other major portion of the structure, 
minus the weight of excavated material, divided by the area, shall not exceed 
one half the tabulated bearing values. 

(f) Where the bearing materials directly under a foundation overlie a 
stratum having smaller allowable bearing values, these smaller values shall 
not be exceeded at the level of such stratum. Computation of the vertical 
pressure in the bearing materials at any depth below a foundation shall be 
made on the assumption that the load is spread uniformly at an angle of 
sixty degrees with the horizontal; but the area considered as supporting the 
1 oad shall not extend beyond the intersection of sixty degree planes of adjacent 
foundations. 

(g) Where portions of the foundation of an entire structure rest directly 
upon or are underlain by medium or soft clay or rock flour, and other portions 
rest upon different materials, or where the layers of such softer materials 
vary greatly in thickness, the magnitude and distribution of the probable 
settlement shall be investigated as specified in section twenty-nine hundred 
and sixteen, paragraph (f), and, if necessary, the allowable loads shall be 
reduced or special provisions be made in the design of the structure to prevent 
dangerous differential settlements. 

(h) Whenever, in an excavation, an inward or upward flow of water 
develops in an otherwise satisfactory bearing material, special methods 
satisfactory to the commissioner shall be immediately adopted to stop or 
control the flow to prevent disturbance of the bearing material. If such 
flow of water seriously impairs the structure of the bearing material, the 
allowable bearing value shall be reduced to that of the material in loose 
condition. 

[ *As amended by Ord. of 1943, eh. 8 and Ord. of 1955, ch. 2 ] 

Sect. 2905. Foundation Loads. — (a) The loads to be used in com- 
puting the maximum pressure upon bearing materials under foundations 
shall be the live and dead loads of the structure, as specified in Part 23, includ - 
ing the weight of the foundations, but excluding loads from overlying soil. 

(b) Eccentricity of loading in foundations shall be fully investigated and 
the maximum pressure shall not exceed the allowable bearing values. 

(c) Where the pressure on the bearing material due to wind is less than 
twenty-five per cent of that due to dead and live loads, it may be neglected in 
design. Where this ratio exceeds twenty-five per cent, foundations shall be 
so proportioned that the pressure due to combined dead, live and wind loads 
shall not exceed the allowable bearing values by more than twenty-five 
per cent. 

fSect. 2906. Foundation Design. — Foundations shall be designed to 
distribute to the supporting media all vertical, horizontal and inclined loads, 

(244) 



Sees. 2906-2907 

as specified in section twenty-nine hundred and five, without exceeding the 
allowable stresses specified elsewhere in this code for the materials of which 
the foundations are to be constructed. Concrete in all foundations shall be 
stone or gravel aggregate concrete and shall be porportioned for an ultimate 
strength of at least fifteen hundred pounds per square inch. 

[ fAs amended by Ord. 1943, ch. 8 and Ord. 1955, ch. 2 ] 

|Sect. 2907. Footings, Caisson Piers and Pile Caps. — (a) The 

footings of foundation walls or piers shall be of plain or reinforced concrete or 

other satisfactory masonry units, footing stones, or steel grillages. Footings 

of wood may be used under temporary structures and, where they are entirely 
below the permanent ground water level, as determined by the commissioner 

under permanent structures of Type V or Type VI. 

(1) Concrete footings and pile caps shall be designed in accordance 
with the provisions of Parts 24 and 26. 

(2) Footing stones shall be at least ten inches in thickness and shall be 
fully bedded. They may be laid dry for buildings not exceeding four 
stories in height. For buildings higher than four stories, they shall be laid 
in cement mortar. Stresses in footing stones shall not exceed the maximum 
specified in Part 24. 

(3) Structural steel grillage foundations and all structural steel below 
grade shall be designed in accordance with the provisions of Part 28, shall 
have at least six inches of concrete below the steel and shall be entirely 
embedded in and surrounded by concrete at least four inches thick between 
steel and soil. 

(4) Wooden footings shall be designed in accordance with the provisions 
of Part 25. 

(b) Caisson piers may be constructed of either plain or reinforced con- 
crete. The unit compressive stress in the concrete at the least cross-section 
shall not exceed 0.225 f . When the height of the shaft H exceeds 18 D, 
such stress shall not exceed 

1.5— H \ 
0.225 f' I I wherein: 



( 



36D/ 



f' c is the ultimate compressive strength of the concrete as specified in 

Part 26. 
H is length of shaft in feet measured from the top of the bell to cut-off. 
D is shaft diameter — in feet when the shaft is of constant cross-section. 
D isd + 0.014H when the shaft increases two inches in diameter each 

six feet plus or minus in height, 
d is shaft diameter in feet at top of bell, 
(c) In reinforced concrete caisson piers the vertical steel shall have an 
area at least one half of one per cent of the minimum area of cross-section 
of the concrete. Such steel shall be stayed laterally by steel ties equivalent 
at least to one quarter inch round bars spaced twelve inches on center. The 
stress in the vertical steel shall not exceed ten thousand pounds per square 
inch. 

C245) 



Sees, 2907=2908 

(d) The bell of a belled pier shall have at least four inches thickness at 
its edge and, unless designed as a spread footing, the sides shall slope at an 
angle of not less than sixty degrees with the horizontal. 

(e) Whenever the center of cross-section of a caisson pier at any level 
deviates from the center of the load more than one sixtieth of its height or 
more than one tenth its diameter it shall be reinforced according to paragraph 
(c) of this section. 

(f ) Piles under buildings of Types I to IV, inclusive, shall be capped with 
concrete proportioned for an ultimate strength of at least two thousand pounds 
per square inch, or with block granite. Concrete capping for piles shall 
extend not less than twelve inches above the pile heads and shall fill the space 
between and around the piles for a depth of at least three inches. The 
minimum horizontal distance from the edge of the cap to the nearest pile 
surface shall be three inches and there shall be at least two inches of concrete 
between the top of a pile and steel reinforcement. Block granite capping 
shall be not less than twelve inches thick. Each block shall have a bearing 
on at least two piles and shall be bedded in cement mortar applied to the pile 
heads. The capping blocks shall be sufficiently large to cover all pile heads. 

(g) Foundation walls shall conform to the requirements of Part 14. 

[$ As amended by Ord. 1943, ch. 8 ] 

*Sect. 2908. Piles — General Requirements. — (a) A detached 
column or pier supported by piles shall rest upon not less than three piles, 
but a column or pier connected to permanent construction, which provides 
adequate lateral support to the top of the piles, may rest upon a single pile, 
or upon two piles. 

(b) A foundation wall of a building not more than one story nor more 
than twenty feet high, if supported laterally by masonry, reinforced concrete or 
steel construction at intervals not exceeding twenty feet, may be supported by 
a single row of piles. If the distance between such lateral supports exceeds 
ten feet, the capping shall be continuous and shall consist of a structural steel 
grillage or reinforced concrete at least two feet wide in which the number of 
square inches of longitudinal steel reinforcement near each vertical face is at 
least one eighth times the length in feet between lateral supports. Other 
foundation walls supported upon piles shall rest upon at least two rows of 
piles. The outer rows shall be at least two feet apart on centers under build- 
ings up to thirty feet in height and at least three feet apart under buildings 
higher than thirty feet. 

(c) The excavation for pile foundations, wherever practicable, shall be 
completed to pile cut-off grade, or lower, before piles are driven. In no case 
shall piles be driven through more than three feet of unexcavated material 
above pile cut-off grade. 

(d) The method of driving shall be such as not to impair the strength 
of the pile and shall meet with the approval of the commissioner. A steel or 
iron follower may be used subject to his approval. It shall be equipped with 
a suitable soeket encasing the pile head sufficiently to prevent damage while 

(246) 



Sees. 2908=2909 

driving. Shattered, broomed or otherwise damaged pile heads shall be cut 
fyack to sound material before driving with the follower. If a wooden driving 
block is used, it shall, at the time it is used for measuring the penetration, 
be of sound hard wood equal to oak, not more than twelve inches in height, 
with the grain parallel to the axis of the pile, and shall be enclosed in a steel 
casing of adequate strength to resist lateral distension. 

(e) Piles shall not be jetted except with specific approval of the com- 
missioner. After jetting, piles shall be driven to the required resistance. 

(f) Additional piles shall be driven to replace piles injured during driving, 
and to supplement piles having capacity less than required by the design. 

(g) Types of pile construction not specifically provided for in this part, 
such as rolled steel sections or other types, shall meet requirements as may 
be prescribed by the commissioner. 

[ *As amended by Orel. 1943, ch. 8 ] 

fSect. 2909. Allowable Load on Piles. — (a) The supporting capacity 
of the piles shall be obtained from bearing upon or embedment in satisfactory 
bearing materials as defined in section twenty-nine hundred and four. 

(b) The allowable pile loading shall be limited by the provision that the 
vertical pressures in the bearing materials at or below the points of the piles 
produced by the loads on all piles in a foundation shall not exceed the allowable 
bearing values of such materials, as specified in sections twenty-nine hundred 
and four, twenty-nine hundred and fifteen, and twenty-nine hundred and 
sixteen. Piles or pile groups shall be assumed to transfer their loads to the 
bearing materials by spreading the load uniformly at an angle of sixty degrees 
with the horizontal, starting at a polygon circumscribing the piles at the 
top of the satisfactory bearing stratum in which they are embedded, but 
the area considered as supporting the load shall not extend beyond the inter- 
section of the sixty degree planes of adjacent piles or pile groups. 

(c) The allowable load on each pile shall be further limited by the require- 
ment that such load shall not cause excessive movement of the pile relative 
to the soil. Satisfactory proof of this load for all soil conditions and all 
types of piles can be obtained from load tests conducted in accordance with 
section twenty-nine hundred and seventeen. In the absence of such proof of 
the supporting capacity, the load on any pile shall not exceed the allowable 
value determined in accordance with paragraphs (d) to (h) inclusive of this 
section. 



(d) 



2Wh 

( 1 ) R = for drop hammers 

s + 1-0 
2Wh 

(2) R = for steam hammers 

s + 0.1 

in which W = weight of striking part of hammer in pounds 

h = height of fall of striking part of hammer in feet 

s = average penetration per blow, in inches, for the last five 

blows 
R = allowable pile load in pounds 

(247) 



Sees. 2909=2910 

(e) For double-acting steam hammers, the value of "s" must be deter- 
mined onty when the hammer is operating at the maximum number of blows 
per minute as scheduled in the Manufacturers' Specifications. 

(f) The data used in determining driving resistance shall be obtained 
during the driving and not upon re-driving when a pile has been allowed to 
stand more than one hour after having been driven. When driving wooden 
piles, broomed heads shall be cut to sound wood before making penetration 
measurements. 

(g) For cast-in-place concrete piles in which the driven casing is with- 
drawn leaving a shell pile of smaller diameter than the outer casing, the pile- 
driving formula may be used for piles in soils of Classes 11 and 12 and it may 
also be used for piles driven into soils of other classes when the supporting 
capacity obtained from the formula is at least doubled in the last three feet of 
driving. 

(h) The commissioner shall require a competent inspector, qualified by 
experience and training and satisfactory to him, to be on the work at all 
times while piles are being driven. The inspector shall make an accurate 
record of the material and the principal dimensions of each pile, of the weight 
and fall of the hammer, if a single-acting steam hammer or drop hammer, 
and the size and make, number of blows per minute, and energy per blow, 
if a double-acting steam hammer, together with the average penetration of 
each pile for at least the last five blows and the grades at tip and cut-off. 
A copy of these records shall be filed and kept in the office of the commissioner. 
Where piles are driven through soft soil to hard bearing material, providing 
high point resistance, the grades of all piles or pile shells previously driven 
shall be measured to detect uplift; and if uplift occurs in any pile or pile shell 
while other piles are being driven, such pile or pile shells shall be rejected and 
additional piles driven to obtain the required resistance. 
[ fAs amended by Ord. 1943, ch. 8 ] 

Sect. 2910. Wooden Piles. — (a) Every wooden pile shall be in one 
piece, cut from a sound live tree, and free from defects which may materially 
impair its strength or durability. It shall be butt-cut above the ground swell, 
and shall have substantially uniform taper from butt to tip. Wooden piles 
shall measure at least six inches in smallest diameter at the tip, at least eleven 
inches in smallest diameter two feet from the butt and at least ten inches in 
smallest diameter at the cut-off, these measurements being taken under the 
bark. The axis of a wooden pile shall not deviate from a straight line more 
than one inch for each ten feet of length nor more than six inches. Square 
timber of approved quality may be used as piling, in which case the average 
cross-section shall be not less than the commercial ten by ten inch section. 

(b) The load on wooden piles shall not exceed the allowable load specified 
in section twenty-nine hundred and nine and, for piles of the minimum dimen- 
sions specified in this section, shall not exceed twelve tons for spruce, Norway 
pine, and woods of similar strength, nor sixteen tons for oak, southern yellow 
pine, and woods of similar strength. These limits may be increased one ton 
for each inch by which the diameters at both cut-off and tip exceed the minima 
specified. 

(248) 



Sees. 2910-2912 

(c) Piles shall be cut to sound wood before capping is placed. The 
cut-off grade shall be determined by the commissioner so as to be below the 
probable permanent ground water level. 

(d) The center- to-center spacing of wooden piles shall be not less than 
twenty-four inches nor less than twice the butt diameter. 

Sect. 2911. Precast Concrete Piles. — (a) Precast concrete piles shall 
be designed, cast and cured to have the strength necessary for handling and 
for driving. The concrete shall be proportioned to have a compressive 
strength of at least three thousand pounds per square inch as specified in 
Part 26. No pile shall be handled or driven until it has cured sufficiently to 
develop the necessary strength as shown by standard test specimens made 
from the same batches of concrete. Each pile shall be cast in one piece. 

(b) Precast concrete piles shall be reinforced, except as otherwise specified 
in this section, in the manner specified for Columns in Part 26. The ratio 
of the area of the longitudinal reinforcement to the cross-sectional area of the 
pile at mid-length shall be not less than two per cent. For a length of four 
feet at both ends of the pile, lateral ties shall be spaced not over three inches 
center-to-center or an equivalent spiral shall be provided. Reinforcing steel 
shall be embedded in the concrete forming the body of the pile at least one and 
one half inches from any exposed surface and in piles exposed to sea water 
such coverage shall be at least three inches. 

(c) The minimum spacing center-to-center of precast concrete piles shall 
be two and one half times the square root of the cross-sectional area at the butt. 

(d) The load on a precast concrete pile shall not exceed the allowable 
load specified in section twenty-nine hundred and nine, and shall not exceed 
thirty tons for a pile of one hundred and sixty-nine square inches cross- 
sectional area. For piles of larger cross-section, this limit of load may be 
increased in proportion to increase in area. 

(e) When precast concrete piles are driven to or into bearing materials 
of Classes 1 to 5 inclusive, or through materials containing boulders, they 
shall have metal tips of approved design. The driving equipment shall be 
such as to avoid injury to the piles. 

Sect. 2912. Cast=in=Place Concrete Piles. — (a) Cast-in-place con- 
crete piles shall be so made and placed as to insure the exclusion of all foreign 
matter and to secure a well-formed unit of full cross-section. In forming 
such piles, the concrete shall not be poured through water. 

(b) The spacing of cast-in-place concrete piles shall be sufficient to insure 
the preservation of the full cross-section. The spacing center-to-center 
shall be not less than twice the average diameter of the embedded portion 
of the pile, nor less than thirty inches. When the center-to-center spacing 
is less than two and one quarter times the average diameter of the embedded 
portion of the pile, or less than thirty-six inches, no pile shall be filled with 
concrete until all adjacent piles within a radius of four and one half average 
pile diameters and not less than five feet have been driven to the required 
resistance. 

(249) 



Sees. 2912=2913 

(c) The load on a cast-in-place concrete pile shall not exceed the allowable 
load specified in section twenty-nine hundred and nine, and shall not exceed 
thirty tons for a conical pile having an eight-inch tip and an average diameter 
of eleven inches, for an uncased cylindrical pile having a diameter of sixteen 
inches and for a cased cylindrical pile having an average diameter of fourteen 
inches. This allowable load may be increased for larger piles in proportion 
to the increase in pile area. 



Sect. 2913. Concrete=Filled Cylindrical Steel Piles.— (a) Piles 
consisting of concrete-filled steel cylindrical shells filled after driving, shall 
have an inside diameter not less than ten inches and a shell thickness of at 
least three-eighths inch, except that ten-inch and twelve-inch piles may have 
a shell thickness of five-sixteenths inch. Splices of shells shall be of such 
material and design as to insure alignment of shells and transmission of the 
load. The ends of each section of the shell shall be perpendicular to its axis, 
and all bearing surfaces shall be smooth and true. The outside diameter 
of the pile shall be at least one fortieth of its length. 

(b) After driving, the inside of the shell shall be carefully cleaned to the 
bottom and its direction and cross-section verified. The cross-sectional 
area shall not vary more than ten per cent from its original cross-section. 
Shells shall be filled with concrete having an ultimate strength of at least two 
thousand pounds per square inch. Concrete shall not be placed in water 
except with written approval of the commissioner after submission of detailed 
specifications for procedure. 

(c) The center-to-center spacing of concrete-filled steel piles, when 
driven open-ended, shall be not less than the diameter of the shell plus ten 
inches, and not less than two feet. When driven with closed ends, the spac- 
ing shall be as provided in section twenty-nine hundred and twelve for cast- 
in-place concrete piles. 

(d) The load on a concrete-filled steel pile shall not exceed the safe load 
on the concrete at four hundred pounds per square inch plus that on the steel 
shell at six thousand pounds per square inch, after deducting one eighth 
inch in thickness from the outside of the tube; nor shall the load carried by 
the steel exceed one half of the total load on the pile. If a pile as actually 
driven is longer than forty diameters, the limit of load specified in this para- 
graph shall be reduced by a percentage equal to the excess length divided 
by the diameter. If splices below the upper section are closer than twenty 
feet, the safe load on the pile shall be reduced five per cent for each splice 
in excess of the number required for twenty-foot spacing. 

(e) The load on a concrete-filled steel pile shall not exceed the allowable 
load determined in accordance with section twenty-nine hundred and nine. 
Where it is positively proven that the piles rest upon sound rock of known 
quality, the allowable bearing value of the rock, instead of the allowable 
load determined in accordance with section twenty-nine hundred and nine 
may limit the allowable load on the pile. 

(250) 



Sees. 2915-2916 

(f) When a single concrete-filled steel pile supports a detached column or 
pier, as provided in section twenty-nine hundred and eight, the load shall 
not exceed two thirds the capacity of the pile determined as provided in 
paragraphs (d) and (e) of this section. 

Sect. 2914. Composite Piles. — (a) Composite piles shall Consist of 
a combination of any two of the types of piles provided for in this part. 
The minimum dimensions of each part shall be those specified for piles of its 
type. The allowable load shall be limited by the strength of the weaker 
type. The joint between the two types shall be constructed so as to prevent 
their separation, maintain alignment and support the load. The design of 
composite piles, method of driving and the details of the joint shall be subject 
to the commissioner's approval. 

(b) The center-to-center spacing of composite piles consisting of a wood 
pile and a cast-in-place concrete pile shall be limited by the requirements of 
cast-in-place concrete piles. 

Sect. 2915. Foundation Load Tests. — (a) Whenever the allowable 
load on a bearing material or on a pile is in doubt, the commissioner may 
require tests to be made to enable him to determine such load, as, in his 
opinion, will not cause dangerous or objectionable settlements. The load so 
determined shall be taken as the allowable load. 

(b) The proposed testing apparatus and specifications of the procedure 
must receive the approval of the commissioner before it is used. Loads shall 
be applied by direct weight or by means of hydraulic jack pressure that is 
automatically maintained constant. Tests shall be made under the super- 
vision of the commissioner. Settlement readings shall be referred to a bench 
mark established at a sufficient distance from the test to be unaffected by it 
and they shall be made by a method which assures accuracy to the degree 
hereinafter specified. 

Sect. 2916. Load Tests of Bearing Materials. — (a) For bearing 
materials of Classes 1 to 5 inclusive, the loaded area shall be at least one 
square foot and for other classes at least four square feet. For materials of 
Classes 6 to 13 inclusive, the loaded area shall be the full size of the pit and 
at such depth that the ratio of the width of the loaded area to its depth below 
the immediately adjacent ground surface is the same as the larger of the 
following two values: 

(1) Ratio of the width of any footing to its depth below the immediately 
adjacent ground surface. 

(2) Ratio of the width of the entire foundation or group of footings to 
its depth below the average surrounding ground surface. 

(b) When loading tests are made on bearing materials of Classes 10 to 13 
inclusive, suitable methods shall be used to prevent evaporation from the 
materials being tested. 

(c) A test load shall be applied which will produce a unit pressure equal 
to that for which the proposed foundations are designed. This load shall be 
allowed to remain undisturbed until no measurable settlement occurs during 

(251) 



Sees. 2916=2917 

a period of twenty-four hours. The load shall then be doubled in increments 
not exceeding twenty-five per cent of the design load. At least four hours 
shall elapse between the application of successive increments. The total 
load shall be allowed to remain undisturbed until no measurable settlement 
occurs during a period of twenty-four hours. 

(d) Measurements of settlement shall be accurate to one thirty-second 
inch and shall be taken and recorded every hour during the first six hours 
after the application of each increment, and at least once every twelve hours 
thereafter. 

(e) When the design load upon bearing materials of Classes 1 to 10 
inclusive causes settlement of less than three eighths inch and twice the 
design load causes settlement of less than one inch, the design load shall be 
allowed; but if medium or soft clay underlies these materials the vertical 
pressure in such clay shall not exceed that allowed in section twenty-nine 
hundred and four. 

(f) Whenever the proposed foundation rests on or is underlain by bearing 
materials of Classes 11 to 13, inclusive, the results of loading tests must be 
interpreted in conjunction with accurate soil profiles showing magnitude and 
variation of the thickness of these strata. If this information, in the opinion 
of the commissioner, is not sufficient to determine whether the design load 
will cause excessive settlement, as might occur due to a thick stratum of 
clay, or dangerous differential settlement, as might occur when the under- 
lying clay stratum varies considerably in thickness, the commissioner may 
require an analysis to be made of the probable magnitude, rate and distribu- 
tion of settlement of the proposed structure. Such analysis may be based 

upon: 

(1) A study of settlement records of nearby structures having essen- 
tially the same foundation conditions. 

(2) Consolidation tests and other investigations of undisturbed samples 
of the compressible materials. 

Sect. 2917. Pile Loading Tests. — (a) A pile to be tested shall be 
loaded to at least twice the proposed working load, the load being applied in 
increments of not over ten thousand pounds. At least four hours shall elapse 
between the addition of successive increments. Measurements of the settle- 
ment, accurate to one thirty-second inch shall be taken and recorded imme- 
diately before and after each increment of load is added. In determining 
the settlement, proper deduction shall be made for elastic compression of the 
pile under the test load. 

(b) The allowable pile load shall not exceed one half of that causing a 
total settlement of one half inch which remains constant for forty-eight hours, 
but the load on the bearing materials at the level of the points or upon any 
1 ower stratum shall not exceed the bearing values specified in sections twenty- 
nine hundred and four and twenty-nine hundred and nine. 



(252) 



Sees. 3001-3002 



PART 30. 

FIRE EXTINGUISHING APPARATUS. 

Section 

3001 — Fire Extinguishing Apparatus Required. 

3002 — Fire Department Standpipes. 

3003 — First Aid Standpipes. 

3004 — Piping for Standpipes. 

3005 — Automatic Sprinklers. 

3006 — Sprinkler Control. 

3007 — Water Supply for Fire Extinguishing. 

3008 — Portable Fire Extinguishers. 

3009 — Inspection and Tests of Fire Extinguishing Apparatus. 
[3010 — Access Panel for Fire Extinguishing Apparatus.] 

*Section 3001. Fire Extinguishing Apparatus Required. — (a) The 

owner of a building in which fire extinguishing apparatus is to be installed, 
altered or repaired (except repair of leaks and other minor repairs) pursuant 
to the requirements of this part, or connected to the water supply of the city of 
Boston, shall first make application to the building commissioner and obtain 
a permit therefor, in the manner specified in section ten of Part 1 and follow- 
ing sections relating to permits. 

(b) Fire extinguishing apparatus shall be installed in buildings where 
specified in Parts 3 to 12, inclusive. The commissioner shall require auto- 
matic sprinklers in the basement or basements of pre-code buildings of occu- 
pancies of Groups E and F or of either of the two combined with occupancies 
of Groups H or I, when in his judgment public safety demands such protection. 

(c) Such fire extinguishing apparatus shall conform to the requirements 
of this part and to such additional requirements as are specified in Parts 3 to 12, 
inclusive. 

(d) All devices used in connection with fire extinguishing systems shall 
have the approval of a recognized testing laboratory and the approval of the 
commissioner or shall comply with the recommendation of the National Fire 
Protection Association. 

[ *As amended by Ord. 1943, ch. 8 ] 

Sect. 3002. Fire Department Standpipes. — (a) A fire department 
standpipe shall consist of a vertical pipe with fire department connection and 
outlet valves with connections for hose at convenient points in a building, by 
means of which the fire department may distribute water through the building 
to hose to be attached by the fire department for extinguishing a fire and pro- 
tection against fire in an adjoining building. 

(b) Fire department standpipes, where required, shall be of such number 
and so located that a stream from a nozzle on not more than one hundred feet 
of hose connected to a standpipe can be played upon every part of each story, 
assuming the stream to reach fifty feet from the nozzle. 

(253) 



Sec. 3002 

(c) Fire department standpipes shall be not less than five inches in internal 
diameter throughout, and in buildings higher than ninety feet, or where the 
standpipe has a roof outlet, not less than six inches. 

(d) Every fire department standpipe shall extend to every story of the 
building and above the roof unless the requirement of a roof outlet is waived 
by the commissioner. Such standpipe shall be located in a stair enclosure or 
other approved location and shall have, in every story above the first, an 
outlet two and one half inches in inside diameter threaded for standard fire 
hose coupling, and an approved angle globe valve. The outlet above the roof 
shall have two such hose connections, each with a valve. Hose outlets shall 
be not more than five feet above the floor, roof or stair landing. Neither the 
standpipe, outlet nor valve shall project within the width required for a 
stairway as an exit. Convenient to every roof outlet shall be provided and 
properly stored not less than fifty feet of approved two and one half inch linen 
hose and a tapered nozzle with one and one eighth inch smooth orifice. 

(e) Every fire department standpipe shall have a fire department con- 
nection in an exterior wall of the building, fronting on a street, in an approved 
location not less than ten inches nor more than forty-eight inches above the 
sidewalk or ground. Two or more standpipes may have a common fire depart- 
ment connection. Where a building is required to have two or more fire 
department standpipes and faces on two streets it shall have two fire depart- 
ment connections remote from one another. The fire department connection 
shall be of approved design, shall have two couplings and if it serves two or 
more standpipes, shall have three couplings of not less than two and one half 
inches inside diameter threaded to receive standard city of Boston fire hose, 
and protected by approved caps. 

(f ) Where a building contains two or more fire department standpipes and 
two or more fire department connections, they shall be cross connected, but 
the commissioner may waive this requirement subject to such condition as he 
may in any case specify. Each fire department standpipe connection shall 
De marked by a cast bronze or brass plate embossed to indicate its connection 
to a standpipe. 

(g) A fire department standpipe shall be connected to an adequate source 
of water supply and if subject to freezing shall be equipped with an approved 
control valve. An approved check valve shall be installed in the water 
supply pipe which will prevent water from the fire department connection 
from backing up in the supply pipes, and a check valve and automatic drain 
shall be installed between the standpipe and the fire department connection 
to prevent water from reaching a point where it would freeze. 

(h) For protection against fire during construction, in a building required 
to have one or more fire department standpipes, they shall be installed with 
fire department connection and extended upward with the building, always 
reaching within one story of the highest constructed floor. During construc- 
tion of the building, such standpipes shall be connected to an approved 
source of water supply and the outlets thereof shall be provided with hose 
and nozzles as required by the commissioner. Water shall be kept turned 
on in such standpipes during construction except in freezing weather and 
when the pipe is being extended. The shut-off valve shall be accessible and 
the standpipes in readiness for use at all times. 

(254) 



Sees. 3003=3005 

*Sect. 3003. First Aid Standpipes. — (a) A first aid standpipe shall 
consist of a pipe or system of pipes connected to an adequate source of water 
supply, with valves, hose connections, hose and nozzles at convenient points 
inside the building for use of the occupants in extinguishing a fire. 

(b) Where first aid standpipes are required they shall have hose stations 
in every story in such number and so loc ated that a stream from a nozzle on 
the length of hose connected to an outlet can be played on every part of the 
story required to have such protection, assuming the stream to reach twenty 
feet from the nozzle. Pipes shall be so located as to be safe from injury by 
frost or otherwise. 

(c) The risers of first aid standpipes shall be not less than two and one 
half inches internal diameter. Branches to singl e hose stations shall be not ' 
less than one and one half inches. 

(d) A first aid hose station shall consist of an angle globe valve, threaded 
hose coupling, not more than fifty feet of approved linen hose, all one and 
one half inches in diameter, and a tapered nozzle with one half inch smooth 
orifice, attached, ready for use and mounted in an approved rack or reel, pref- 
erably in a cabinet. The valve and hose shall be not over five feet above the 
floor. 

(e) First aid hose stations shall be located in corridors or other approved 
locations and shall be visible and accessible at all times. 

(f) A fire department standpipe may serve as piping for a first aid stand- 
pipe if it is connected to an adequate water supply as provided in section 
thirty hundred and two but there shall be no interference between first aid 
hose stations and fire department outlets. 

[ *As amended by Ord. 1943, ch. 8 ] 

jSect. 3004. Piping for Standpipes. — (a) Pipe for fire department 
or first aid standpipes shall be of wrought iron or steel of standard weight 
except that extra heavy pipe and fittings shall be used where the normal 
water pressure may exceed one hundred and seventy-five pounds per square 
inch. 

(b) Piping shall be connected by screw fittings, flanges or unions; right 
and left fittings shall not be used. Fittings for changes in direction in pipes 
more than two inches in diameter shall be standard fittings. Reduction in 
pipe size shall be made by reducing fittings. 

[ f As amended by Ord. 1948, ch. 8 J 

JSect. 3005. Automatic Sprinklers. — (a) Where automatic sprin- 
klers are required, the system of sprinklers and piping shall be designed to 
spray walls, ceilings and every portion of the floor space in accordance with 
the requirements of this part, except that arrangement and placement of 
sprinklers in accordance with the requirements of the National Fire Protec- 
tion Association or the National Board of Fire Underwriters, shall be accepted 
as meeting the requirements of Sections 3005, 3006 and 3007 of this code. 

(b) Where ceilings are smooth and unbroken there shall be a sprinkler 
for approximately every one hundred square feet and the spacing in a line 
shall not exceed twelve feet. 

(255) 



Sec. 3005 

(c) Where ceilings are of wooden joist construction the spacing of sprin- 
klers shall not exceed eight feet at right angles to the joists nor ten feet parallel 
to the joists and sprinklers shall be staggered at third points of the spacing 
in lines at right angles to the joists. 

(d) Where ceilings have beams not less than five nor more than twelve 
feet apart on centers, sprinklers shall be placed midway between beams not 
over twelve feet apart and with not more than one hundred square feet of 
ceiling for each sprinkler. 

(e) Sprinklers shall be placed under all soffits, inclined surfaces, decks, 
tables, benches, shelving, mezzanines, balconies or other similar construction 
more than forty-two inches wide when fixed against walls and more than 
sixty inches wide when such fixtures are clear of walls or partitions, within 
floor areas where sprinklers are required. 

(f) Sprinklers shall not be placed closer than twelve inches from posts, 
walls, hangers or other vertical construction. Sprinklers, where required, 
shall be placed not further from walls and partitions than half the allowed 
spacing in the given direction, and under a joisted ceiling, not more than two 
feet. 

(g) Sprinklers shall be placed preferably upright and the deflector shall 
be not more than ten inches nor less than three inches from the ceiling or 
soffit to be sprayed, the stream from the orifice perpendicular thereto. 

(h) Sprinklers shall be of a type and construction approved by the com- 
missioner and shall be designed to release at not more than seventy-five 
degrees Fahrenheit above the maximum temperature to be expected at the 
location where installed. 

(i) Pipe for sprinkler systems shall be of wrought iron or steel, of standard 
weight and size, or other approved pipe, and shall have not less than the fol- 
lowing inside diameters, depending on the number of sprinklers within one 
story and fire division supplied through each section of pipe. 

Minimum Pipe Sizes for Automatic Sprinklers. 



Number of Sprinklers. 


Minimum Pipe 
Size (Inches). 


1 


3 


2 


1 


3 


u 


5 


11 


10 


2 


20 


2| 


36 


3 


55 


3| 


80 


4 


140 


5 


200 


6 


400 


8 







(256) 



Sees. 3005-3006 

(j) In buildings of Type I and Type II construction, the commissioner 
may allow not more than two hundred and fifty sprinklers to be supplied 
through a six-inch pipe and not more than five hundred sprinklers through 
an eight-inch pipe, in one story and fire division. 

(k) Piping shall be connected by screw fittings, flanges, or unions; right 
and left fittings shall not be used. Fittings for changes in direction in mains 
and risers shall be standard fittings. Reduction in pipe size shall be made 
by reducing fittings. 

(1) The system of sprinkler piping shall be well supported and pitched to 
drain completely. Piping and equipment shall be safe from injury by frost 
or otherwise. 

(m) Sprinkler systems or portions thereof subject to freezing shall be 
equipped with approved dry pipe valves. The capacity of a system depending 
upon a single dry valve shall not exceed three hundred twenty-five gallons 
unless provided with a quick opening device, in which case the capacity shall 
not exceed five hundred seventy-five gallons. The air pressure maintained 
in a dry pipe system shall not exceed thirty-five pounds. Every dry pipe 
valve shall be equipped to give an alarm upon operation. The commissioner 
may allow that part of an automatic sprinkler system controlled by a cold 
weather valve to be shut off and drained in cold weather subject to such 
conditions as he shall in any case specify and the Fire Commissioner so notified 
in writing by the department. 

(n) Nothing in this code shall be construed to prohibit the installation 
of a system of sprinklers containing twenty-five or less heads attached to the 
domestic water supply, provided the system is not mandatorily required 
elsewhere by this code. 

HAs amended by Ord. 1943, ch. 8 and Ord. 1955, ch. 2} 

*Sect. 3006. Sprinkler Control. — (a) The main supply pipe of a 
sprinkler system and each connection to the service main, if more than one, 
shall have a gate valve of approved indicator pattern with bronze stem, a 
check valve, test pipe and pressure gage, installed in approved locations. 
The main supply pipe of the system shall have a visible flow test pipe not 
less than one and one half inches in diameter with approved discharge. Valve 
stems shall not be placed below the horizontal and shall be within seventy- 
eight inches from the floor or shall be made accessible by permanent ladders 
fixed in place, or other approved means. Where sprinklers in two or more 
fire divisions are supplied through one or a set of two or more service con- 
nections, each fire division shall have a separate branch supply pipe with 
control valve and drain. Every required sprinkler system shall have a fire 
department connection, except that the commissioner may waive this require- 
ment, subject to such conditions as he may specify, where the protected 
space is visible and directly accessible from a street or alley or where the 
number of sprinklers in any story and fire division does not exceed twenty-five, 
(b) A fire department connection shall be of approved design and threaded 
for two and one half inch standard city of Boston fire hose and protected by 
approved caps. The pipe leading therefrom shall have a check valve and an 
automatic drain to prevent water from reaching a point where it would freeze. 

(257) 



Sees. 3006=3007 

(c) Every fire department sprinkler connection shall be marked with 
a cast bronze or brass plate embossed to indicate its connection to sprinklers. 

(d) Every system of automatic sprinklers shall be connected to a per- 
manent and adequate water supply as provided in section thirty hundred 
and seven. 

(e) An inspector's test valve shall be installed at the top of every auto- 
matic sprinkler system. 

(f) Where a main supply pipe serves automatic sprinklers in a basement 
or sub-basement concealed from view, or a remote building or a garage or 
part of a building, an approved sprinkler alarm shall be provided unless the 
commissioner shall waive this requirement. 

(g) Neither goods, furniture, machinery or other materials or equipment 
shall be so placed as to interfere with the effectiveness of sprinklers nor shall 
sprinkler piping be used to support such materials or equipment. 

[ *As amended by Ord. 1943, ch. 8 ] 

fSect. 3007. Water Supply for Fire Extinguishing. — (a) Water 
supply for required fire extinguishing apparatus shall be taken from the 
"high service" city water mains where available and, except when general 
service is permitted, shall be independent of the supply for sanitary, in- 
dustrial or other purposes. 

(b) In buildings where first aid standpipes or automatic sprinklers are 
required and where the city water supply, with a sufficient flow properly to 
supply the sprinklers, will not furnish a pressure of at least thirty-five pounds 
per square inch at the highest first aid hose station, and twelve pounds per 
square inch at the highest sprinkler, an auxiliary water supply for fire ex- 
tinguishing apparatus shall be provided. 

(c) An auxiliary water supply for fire extinguishing apparatus shall 
consist of a storage tank or a fire pump or both. A storage tank shall be 
either gravity or approved pressure type. 

(d ) A gravity storage tank shall have a capacity not less than five thousand 
gallons of water and the bottom of the tank shall be not less than twenty feet 
above the highest sprinkler or hose outlet. The tank and connected pipes 
shall have protection from freezing. 

(e) A pneumatic pressure storage tank of such capacity (not less than 
thirty-five hundred gallons of water) and design, and with such automatic 
pumping equipment as will furnish as much water, at the same pressure* 
at the upper outlets of the S3^stem, as the gravity storage tank specified in 
paragraph (d) of this section, may be substituted therefor with the approval 
of the commissioner. 

(f) A fire pump, to serve as an auxiliary water supply, shall be auto- 
matically controlled, shall be connected to the city mains and shall be capable 
of delivering water at the rate of twenty gallons per minute for each sprinkler 
up to fifty in any one story and fire division, against a head sufficient to 
furnish a pressure of twelve pounds per square inch at the highest sprinklers 
and of thirty-five pounds per square inch at the highest outlets of connected 

(258) 



Sees. 3007=3010 

standpipes in the building and shall be of a type satisfactory to the commis- 
sioner. A fire pump shall be connected to a permanent, reliable and approved 
source of power. 

(g) Auxiliary water supply equipment shall have all necessary approved 
gate and check valves. Motors and other electrical equipment shall be en- 
closed, or protected by a hood and by a grille or partition of incombustible 

[ \As amended by Ord. 1943, ch. 8 ] 

Sect. 3008. Portable Fire Extinguishers.— (a) A portable fire 
extinguisher shall consist of a container holding not less than two and one half 
gallons of extinguishing liquid so arranged and equipped that pressure may 
be generated and the contents discharged through a hose and nozzle; or a 
portable extinguisher of other type approved as equal thereto by the fire 
commissioner. The design and construction of portable fire extinguishers 
shall be approved by the fire commissioner. 

(b) Portable fire extinguishers, where required, shall be mounted in 
corridors or other approved locations generally visible to the occupants of the 
building. Where they are placed in cabinets they shall be visible and the 
doors shall be unlocked or of glass which can be broken to give access to the 
extinguisher in case of fire. 

(c) Portable fire extinguishers shall be discharged and recharged as often 
as shall be generally required by the fire commissioner for extinguishers of 
each type, and shall be recharged at once after use. 

JSect. 3009. Inspection and Tests of Fire=Extinguishing Ap= 
paratus. — (a) Every system of automatic sprinklers and all parts thereof 
shall satisfactorily meet a pressure test of two hundred pounds per square 
inch and when water pressure is over two hundred pounds it shall be tested 
to fifty pounds above the highest static pressure. 

(b) Standpipes and all parts thereof except hose shall satisfactorily meet 
a pressure test of two hundred and fifty pounds per square inch at ground 
level. 

(c) First aid hose and other hose required for extinguishing purposes 
shall satisfactorily meet a pressure test, unless this requirement is waived by 
the building commissioner, in his presence, when first installed, and shall be 
thoroughly dried before it is hung in racks or reels. 

(d) All required fire extinguishing apparatus, except as provided in 
section three thousand and eight, shall be inspected at least once each year 
and such tests shall be made as the building commissioner shall require. 
Defective hose and other defective parts shall be replaced without delay on 
order of the building commissioner. 

(e) Piping shall not be concealed until tested and approved. 

[ %As amended by Ord. 1943, ch. 8 } 

*Sect. 3010. Access Panel for Fire Extinguishing Apparatus.— 

Where basement or cellar space below the ground floor of a store is used for 
storage purposes of any description access panels shall be provided in open- 
ings incorporated in the ground floor construction for use of fire department. 

(259) 



Sec. 3010 

Each access panel opening shall be a minimum of ten inches square and pro- 
vided with a removable cover of suitable strength to receive the live load for 
which the floor is designed. This removable cover shall be easily distinguish- 
able from the rest of the floor. One such opening shall be located ten feet in 
from the main entrance door to store in line perpendicular to door. There 
shall be additional access panel openings in the same continuous line as the 
initial installation every twenty feet or portion thereof so that each opening 
shall provide provisions for fire extinguishing apparatus to cover each four 
hundred square feet of floor space. Where finished material of floor would 
cover or conceal access panel such covering shall be painted red directly over 
each opening. 

Where ceiling material is provided on the under side of ground floor con- 
struction the access panel openings shall be provided with a breakable glass 
seal located below the removable cover. This glass seal may be located at 
the level of the ceiling, if above the level of the ceiling the four sides of the 
panel opening between the ceiling and the removable cover shall be finished 
with the materials joining the ceiling proper, or equivalent fire-resistive 
material. 

The above requirements shall not apply if the basement or cellar is equipped 
with an approved automatic sprinkler system. 

[ *As amended by Ord. 1943, ch. 8 ] 



(260) 



Sec. 3101 



PART 31. 

PLUMBING. 

Section 

3101 — Plumbing in Buildings. 

3102 — Definitions pertaining to Plumbing. 

3103 — The Drainage System. 

3104 — Soil and Waste Pipes. 

3105 — Rain Water Drains. 

3106 — Indirect Wastes. 

3107 — Mechanically Discharged Drainage. 

3108 — Traps. 

3109 — Venting. 

3110 — Vent Pipes. 

3111 — Buildings more than One Hundred and Twenty=five Feet 

High. 

3112 — Materials of the Drainage System. 

3113 — Water Supply. 

31 14 — Hot Water Supply. 

3115 — Plumbing Fixtures and Units. 

3116 — Cast Iron Pipes. 

3117 — Wrought Iron and Steel Pipes. 

3118 — Brass, Copper and Lead Pipes. 

3119 — Hangers and Supports. 

3120 — Inspection and Tests. 

3121 — Prohibited Fixtures, Fittings and Connections. 

[ All heading as amended by Ord. 1943, ch. 8] 

*Section 3101. Plumbing in Buildings. — (a) Every building where 
people live, work or assemble shall have a supply of pure and wholesome 
water and a drainage system. 

(b) Every building shall have such, toilet accommodations and plumbing 
fixtures as are specified in Parts 3 to 12, inclusive, of this code or as required 
by any Massachusetts State Law or Regulation. If not so covered, to be as 
directed by the Building Commissioner or Health Commissioner of the City 
of Boston. 

(c) Plumbing fixtures shall not be installed in rooms which do not con- 
form to the requirements of this code. 

(d) A permit to install, alter or repair plumbing shall not be issued unless 
the work is to be performed under the supervision of a master plumber, 
licensed under chapter one hundred and forty-two of the General Laws and 
registered by the Commissioner. An application for a permit for plumbing 
shall be signed as provided in section one hundred and ten of this code by a 
licensed and registered master plumber. 

(e) Every master plumber holding a certificate issued in accordance with 
section three of chapter five hundred and thirty-six of the Acts of nineteen 
hundred and nine, section two of chapter five hundred and ninety-seven of 

(261) 



Sees. 3101=3102 

the Acts of nineteen hundred and ten or chapter five hundred and eighteen 
of the Acts of nineteen hundred and twelve, or licensed under chapter one 
hundred and forty-two of the General Laws, and has a business address in 
Boston or does business in Boston, shall personally register his name and 
business address with the Commissioner each year on or before the fifteenth 
day of May. He shall give the Commissioner immediate notice of any change 
in his business address. 

[ *As amended by Ord. 1948, ch. 8 ] 

fSect. 3102. Definitions Pertaining to Plumbing. — For the purpose 
of this part of the code the words and terms defined in this section shall be 
construed as so defined except when qualifying words or the context clearly 
indicate that another meaning is intended. 

Plumbing. — Plumbing is the art of installing in buildings the pipes, 
fixtures and other apparatus for bringing in the water supply and removing 
liquid and water-carried wastes; also, the system of pipes, fixtures, and other 
apparatus installed in buildings for distributing the water supply and for 
the disposal of liquid and water-carried wastes, including valves, traps, soil, 
drain, waste and vent pipes. 

Plumbing System. — The plumbing system of a building includes the 
water supply distributing pipes; the fixtures and fixture traps; the soil, 
waste and vent pipes; the storm water drainage; with their devices, appur- 
tenances, and connections all within or adjacent to the building. 

Master Plumber. — A plumber who is licensed under chapter one hundred 
and forty- two of the General Laws as a Master plumber having a regular 
place of business and who, by himself, or journeyman plumbers in his employ, 
performs plumbing work. 

Journeyman Plumber. — A person who is licensed as a journeyman 
plumber under chapter one hundred and forty-two of the General Laws and 
who installs plumbing in the employ and under the direction of a master 
plumber. 

Battery of Fixtures. — A group of fixtures of one type, at the same level, 
not less than three in number. 

Branch. — That part of a system of piping which extends from the main 
to a fixture or fixtures and which serves to connect to the main the fixtures 
which are not directly connected thereto. 

Building Drain. — That part of the lowest horizontal piping of a building's 
drainage system which receives the discharge from soil, waste and other 
drainage pipes inside the walls and extends to a point ten feet outside the inner 
face of the exterior walls. 

Indirect Waste Pipes. — A waste pipe which is not directly connected 
to the drainage system but discharges into an open sink or other fixture. 

Length of Pipe. — The developed length of pipe and fittings as connected, 
measured along the center line. 

Main. — A general term signifying the principal line of a system of piping 
from which branches extend to fixtures. 

Plumbing Fixture. — A receptacle or outlet intended to receive and 
discharge water, liquids or water-carried wastes into a drainage system either 

(262) 



Sees. 3102=3103 

directly or indirectly or to some other place that the Building Commissioner 
may approve. 

Repair of leaks. — Such repairs as are necessary to protect property but 
do not involve change in construction. 

Soil Pipe. — A pipe which conveys the discharge of water-closets, with or 
without the discharge of other fixtures, to the building drain. 

Stack. — A general term for vertical line of soil, waste or vent piping. 

Trap. — A fitting or device so constructed as to prevent the passage of 
air or gas through a pipe without materially affecting the flow through it of 
sewage or waste water. 

Trap Seal. — The vertical distance between the crown weir and the invert 
of the trap outlet. 

Vent Pipe. — A pipe provided to ventilate a drainage system and to prevent 
back pressure and trap siphonage. 

Waste Pipe. — A pipe which receives the discharge of any plumbing 
fixture except a water closet, and conveys it to the building drain or to a soil 
pipe. 

Water Distribution Pipe. — A pipe which conveys water from the water 
service pipe to or from a faucet, valve or any piece of equipment requiring 
water. 

Water Service Pipe. — The water supply pipe from the City main to the 
building served. 

Cross Connection. — Any connection whereby the potable water supply 
may become contaminated by any other substance or liquid. 
[ -\As amended by Ord. 1943, ch. 8 } 

JSect. 3103. The Drainage System. — (a) The entire drainage system 
shall be so designed, constructed and maintained as to dispose of sewage 
and liquid wastes with velocities of flow that will avoid the deposit of solids 
and prevent clogging the pipes. The drainage pipes shall be so designed, 
constructed and supported as to be free from leakage of water, air or gas 
through defective materials, imperfect connections, corrosion, settlement, 
vibration, temperature changes, freezing or other causes. The entire system 
shall drain, completely. No cement joints nor connections between iron 
and cement or tile pipe or brick drain shall be made within any building. 

(b) The plumbing drainage system of every building shall be separately 
and independently connected, outside of the building to the public sewer if 
such sewer is accessible, to an approved private sewer or, if a sewer is not 
accessible, to an approved cesspool or septic tank; except that two or more 
buildings may have a common sewer if approved by the Building Com- 
missioner and the Commissioner of Public Works. Sewage discharge into a 
cesspool shall have such treatment as the Commissioner and the Health 
Commissioner shall require. 

(c) No substances which will clog the drains, produce explosive mix- 
tures or injure the pipes or their joints shall be allowed to enter the drainage 
system or the sewer. 

(d) Steam, vapor, and water at a temperature above one hundred and 
thirty degrees Fahrenheit shall not be discharged into the sewer. The 

(263) 



Sec. 3103 

blow-off of boilers, steam exhaust or drip, or hot water from any other source 
destined to be discharged into a sewer shall first be condensed and cooled 
to one hundred and thirty degrees Fahrenheit in a blow-off tank or other 
approved device of which the size, arrangement, location, venting and all 
connections shall be subject to the approval of the Commissioner and the 
Commissioner of Public Works. 

(e) A blow-off tank of approved design and connections, connected to 
one or more high pressure boilers shall have a capacity not less than thirty 
per cent of the largest boiler to which it is connected. Every blow-off tank 
shall have a vapor pipe not less than two inches in size extending above the 
roof and above any window within fifteen feet. 

(f) Where a drainage system may be subjected to back flow of sewage 
suitable provision shall be made, by means of a gate and check valve or 
otherwise approved device, controlling fixture branches subject to back 
flow from the main drain. 

(g) The building drain shall have a Y-branch fitting with an end cleanout 
or with an iron stopper near the point where it leaves the building. The 
cleanout shall be in a straight line with the drain as it passes through the wall. 
The drainage system shall have an adequate number of cleanouts so arranged 
that any stoppage in the pipe can be readily cleared. Cleanouts in drains 
under ground shall be made accessible. Other cleanouts shall be so located 
as to be accessible or to be made accessible through removable panels or 
otherwise. 

(h) A building drain shall not be smaller in any portion than the largest 
soil or waste pipe or stack entering the drain. 

(i) Stable fixtures and their drainage piping shall be installed in a manner 
approved by the Commissioner. 

(j) A building drain shall have a fall of not less than one-eighth inch 
per foot of run and its size shall not be less than required for the fixtures 
which discharge through it as provided in the following table in accordance 
with the number of fixture units assigned to each type of fixtures as specified 
in section thirty-one hundred and fifteen. Schedule Paragraph E. 



Maximum Number of Fixture Units for Pipe Size. 



Pipe Line (Inches) 


Drains. 


Stacks. 


U 


1 

2.5 

9 

21 

45 

150 

370 

720 

1860 

3600 

6300 

11600 


1 


U 


3.5 


2 


12 


?!*- 


— No Water Closets 


27 


3 — 


- 1 Water Closet by permission 


72 


4.. 




210 


5 


540 


6 


1050 


8 


2640 


10 


5250 


12 


9300 


15 


16800 







(264) 



Sees. 3103=3105 

(k) Changes in direction of building drains shall be made with Y-branches 
or long sweep fittings. Such changes in direction of building drains shall 
have full size cleanouts up to four inch in size and not less than four inch for 
sizes larger, at or near the change of direction and at or near the foot of all 
stacks. Cleanouts shall not be over fifty feet apart on straight runs. Drains 
shall not be laid in filled ground without adequate support to the building 
structure. Drain pipes passing under walls shall be free from stress. 

(1) All other connections to the drainage system shall be made with 
Y-branches or sweep fittings with the exception of vertical soil or waste pipe 
connections which may be made with short pattern TY's. Tee connections 
may be used on vents only. 

(m) Offsets in vertical soil, waste, vent and conductor stacks shall be 
made as direct as possible and short radius fittings shall not be used. 
[ XAs amended by Ord. 1943, ch. 8 ] 

*Sect. 3104. Soil and Waste Pipes. — (a) Soil and waste pipes from 
plumbing fixtures shall discharge into the building drain. 

(b) Every building drain serving water closets or pedestal urinals shall 
have at least one four-inch diameter vent extension through roof. Branches 
of soil or waste pipes, if more than twenty feet long, shall be extended through 
roof or connected to vent stack undiminished in size, except that a two-inch 
waste stack may be connected at the bottom to a three-inch waste if the 
number of connected fixture units does not exceed eight. 

(c) A horizontal branch of soil or waste pipe shall have a fall not less than 
one-eighth inch per foot of run. 

(d) The maximum developed length of one and one half inch or smaller 
waste pipe shall not exceed fifty feet. 

(e) No soil pipe shall be less than four inches in size, except that a three- 
inch soil pipe may be used for one water closet, with the approval of the 
commissioner, where it is not practicable to use a four-inch pipe. 

(f ) No waste pipe where buried underground shall be less than three inches 
in size. 

(g) In buildings more than one hunched and twenty-five feet high, soil 
stack shall be at least five inches, waste stacks serving slop sinks or urinals 
shall be at least four inches and waste stacks serving lavatories shall be at 
least three inches in size. 

[ *As amended by Ord. 1948, ch. S ] 

fSect. 3105. Rain Water Drains. — -(a) All rain water drains from 
roofs, including area drains and surface drains, shall be kept separate from 
the building drainage system of a building, except as provided in this section. 
Area drains and surface drains may be connected to the building drainage 
system or otherwise disposed of only with the approval of the commissioner, 
(b) Where a storm water sewer is accessible rain water drainage shall be 
discharged therein. In locations where the commissioner shall indicate that 
storm water sewers may presently be laid, the main rain water drain shall 
extend at least ten feet from the inner face of the foundation wall and may 
there be connected to the building sewer. Elsewhere the rain water shall be 

(205) 



Sees. 3105=3106 

discharged into the building drain near the point where it leaves the building , 
or otherwise disposed of in such manner as not to flow upon a public way or 
neighboring land. 

(c) A main rain water drain outside a building, except where a storm 
water sewer exists shall be laid not lower than four feet below street grade. 

(d) Rain water leaders shall not project into a public way more than 
seven inches. 

(e) All rain water piping shall have a fall of not less than one eighth inch 
per foot of run. The size of a rain water drain or leader branch shall be not 
less than as provided in the following table. 

Maximum Horizontal Projection of Drained Area. 



Pipe Size (Inches) 


Area (Square Feet) 


2 


600 


3 


1750 


4 


3600 


5 


6300 


6... 


8000 


8 


16000 


10 


25000 


12 


40000 







When and where the rain water and sanitary systems are combined, the 
area of the combination drain pipe shall be not less than sixty-six and two- 
thirds per cent of the sum of the pipe areas discharged into it. 
[ -\As amended by Ord. 1943, ch. 8 ] 

JSect. 3106. Indirect Wastes. — -(a) Drips from refrigerators, ice 
boxes or other containers in which food is stored, heated or cooled shall not be 
directly connected to soil or waste pipes or any other part of the drainage 
system, but shall discharge in open sight into an open fixture which shall have 
a supply of running water. Wastes of instrument sterilizers, aspirators, 
compressors, stills, vacuum and other similar equipment shall enter trap 
through a visible broken connection of not less than one and one half inches 
long. Trap to be located as close to the fixture as practicable. 

(b) Indirect wastes discharging into open fixture from fish storage tanks, 
corn beef tanks, or window display tanks and similar equipment shall be a 
separate system and the end of the indirect waste shall be extended independ- 
ently above the roof for ventilation. 

(c) Each fixture and piece of equipment wasting into indirect waste pipes 
shall have separate traps. 

(d) An indirect waste serving two or more fixtures or pieces of equipment 
shall be extended through the roof independently. 

(266) 



Sees. 3106=3108 

(e) Vapor vents, from sterilizers and other hospital equipment, where 
required shall be installed as a separate system terminating above the roof. 

(f) Layouts of all indirect waste systems shall be submitted for approval 
to the building commissioner. 

[ %As amended by Ord. 1943, ch. 8 ] 

*Sect. 3107. Mechanically Discharged Drainage. — (a) Floor drains, 
drips from machinery and other clean wastes approved by the commissioner, 
too low to drain by gravity to the sewer, may drain to an open sump or receiv- 
ing tank and thence be discharged by mechanical means into the gravity 
drainage system. The discharge pipe shall be equipped with a check valve 
and shall be trapped with a deep seal trap. 

(b) Where the whole or a part of a drainage system receiving the discharge 
of soil and waste pipes, other than those provided for in the preceding para- 
graph, is too low to drain by gravity to the sewer it shall drain to a closed iron 
sump or receiving tank and thence be discharged by mechanical means, 
automatically operated, into the gravity building drain or directly to the 
sewer. Such closed iron sump or receiving tank shall form part of the drainage 
system and shall be made tight and be tested as provided for other parts of the 
system. It shall be vented by means of an independent vent pipe not less 
than four inches in size extended through the roof as provided for vent stacks 
in section thirty-one hundred and ten, or connected to a vent stack not less 
than four inches in size at least twenty feet above the tank, or may be properly 
connected to the vent stack of the fixtures discharging into the sump if such 
vent is four inch size or larger. 

(c) The discharge pipe from a sewage ejector shall not be less than four 
inches in size and shall be fitted with a check and gate valve. 

(d) The plumbing fixtures which drain to a closed sump or receiving tank 
for mechanical discharge shall have waste or soil pipes, traps and vent pipes 
as provided for in gravity drainage. Such vent pipes shall be extended inde- 
pendently through the roof or be connected to a vent stack not less than 
twenty feet above the tank, or at least above the rim or over-flow point of the 
lowest fixture of the gravity drainage system. 

(e) Drainage discharged by mechanical means into the gravity drainage 
system within a building, as provided in this section, shall discharge into the 
top of the receiving drain. 

(f) Where closed sumps for wastes other than sewage are used, they shall 
have a chamber vent not less in size than the size of the inlet. 

[ *As amended by Ord. 1943, ch. 8 ] 

fSect. 3108. Traps. — (a) Except as otherwise provided in this section, 
the waste pipe of every plumbing fixture shall have a separate trap to prevent 
emission through the fixture of foul air from the drainage system. Such trap 
shall be placed as near the fixture which it serves as is practicable. 

(b) Single tray or sink may be fitted with a one and one half inch trap. 
A two part or a three part tray may be considered as one fixture and shall 
be fitted with a trap, the outlet of which shall be not less than two inches in 
size. Two part tray, three part tray, combination of two trays and one sink 

(267) 



Sec. 3108 

when close together, combination sink and tray, each of which may be con- 
sidered as one fixture and shall be fitted with a trap, the outlet of which shall 
be not less than two inches in size. Where a two inch half S trap is used, the 
combined waste to the inlet side of the trap shall be not less than two inch 
in size. When placed on the same level the waste pipe from the traps of two 
fixtures of like type and used for the same purpose may be connected to the 
branch openings of a long pattern double TY type of fitting placed in an upright 
position and shall require no other vent than the continuation of the waste 
serving these two fixtures undiminished in size. 

(c) The waste pipes from dishwashers or sinks discharging grease in a. 
kitchen of a hotel, restaurant or club shall have individual grease traps of 
approved capacity and type or else shall waste into a master grease trap and', 
system. When individual approved grease traps are used they shall be- 
easy of access to open and clean and placed as near as practicable to the 
fixture which they serve. 

(d) The waste pipe from every floor drain or other fixture from which, 
in the opinion of the commissioner, grease may be discharged in such quan- 
tity as to clog or injure the drain, shall have an approved grease trap. A 
master grease trap will be allowed in lieu of separate grease traps when sepa- 
rate system of drainage is installed for fixtures requiring a grease trap. The 
master grease trap must be in an accessible location for cleaning. Master 
grease trap will be required in lieu of separate grease traps on individual 
fixtures, when in the opinion of the building commissioner it is necessary, 
to protect the drainage system and public sewer from grease. When a 
master grease trap is installed, each fixture discharging into a master grease 
trap shall be fitted with individual one half S trap properly vented. Master 
grease traps shall be approved by the commissioner as to capacity and type. 

(e) The waste pipe from every floor drain or other fixture from which 
gasoline, naphtha or other inflammable liquid may be discharged to a sewer 
shall have a special trap approved by the commissioner of public works so 
constructed as to prevent the passage of such liquids or gas into the sewer. 
Plans of approved type may be procured at the office of the commissioner. 
When a gasoline separator serves floor drains on the same level as the gaso- 
line separator and each entering the gasoline separator independently and 
within fifteen feet they shall require no other than the chamber vent. 

(f) The waste pipe from wash stand for vehicles shall have an approved 
trapped combination floor drain and sand arrestor not less than four inch in 
size. 

(g) The waste pipe from an area drain or surface drain shall have a deep 
seal trap. 

(h) Traps shall be installed in all conductor leaders terminating below 
the main roof, or roofs used for any purpose, other than weather protection. 
Separate traps may be omitted if main roof drain is properly trapped. 

(i) Every trap installed shall be so located as to be accessible. 

(j) Every trap shall have a water seal of at least one and one half inches. 
Deep seal traps shall have a water seal of at least four inches. 

(k) All fixture trap cleanouts shall be water sealed. 

(268) 



Sees. 3108=3110 

(1) Slip joints or unions shall not be used on the outlets of traps. 

(m) Threaded outlet connections on all screw traps shall be iron pipe 
size. 

(n) Iron traps less than two inch in size shall not be used where concealed. 

(o) Non-syphon trap shall only be used by special permission of the 
commissioner and when so used shall be of an approved type and shall have 
a depth of seal not less than four inches. 

[ fAs amended by Ord. 1943, ch. 8 ] 

|Sect. 3109. Venting. — (a) The drainage system shall be so designed 
that there will be circulation of air in all pipes thereof and no danger of 
syphonage, aspiration or forcing of trap seals under conditions of ordinary 
use. 

(b) Traps, except non-syphon traps where approved, shall be protected 
from syphonage or air pressure by separate vent pipes, not less in size than 
the outlet of the trap they serve, except as otherwise provided in this section. 

(c) The trap for the fixture having the highest connection to a soil or 
waste stack need not have separate vent pipe if within five feet from the 
stack and the soil or waste pipe is not connected to the soil or waste stack 
below the invert of the trap, with the exception of closets and similar fix- 
tures which shall be connected to soil or waste stack not more than eighteen 
inches below the weir of the group. 

(d) The traps of a battery of water closets, pedestal and stall urinals and 
bed pan washers, may have, instead of separate vent pipes, a vent pipe con- 
nected to the common waste or soil pipe just before the branch from the 
fixture most remote from the waste or soil stack and between the first fixture 
and the soil or waste stack. If such a battery has more than six fixtures 
there shall be a similar vent pipe connection before the branch from every 
sixth fixture and in no case shall there be more than five fixtures between the 
vents. Vents shall not be less than four inch in size. This type of venting 
may be used only when the vertical distance between the water level of the 
trap and the top of the common waste or soil pipe is not more than twenty- 
four inches and where the developed length of the branch waste or soil pipe 
is not more than three foot six inches between the center line of the common 
waste or soil pipe and the water level of the trap. Water closets and pedestal 
urinals shall be considered one type. No other fixtures shall enter the battery 
system. The commissioner shall prepare explanatory sketches showing the 
method of construction described in this section. 

(e) Single floor drains shall be separately vented unless otherwise noted. 
Groups of two or more floor drains discharging through separate branch 
waste pipes not more than fifteen feet long into four inch or larger main 
waste pipe serving floor drains only, may be vented on the outlet side of the 
end floor drain, by means of an extension of the main waste pipe undiminished] 
in size as a vent pipes, 

[ $As amended by Ord. 1943, ch. 8 ] 

*Sect. 31 10. Vent Pipes. — (a) The vent pipes from traps and the 
extension of soil and waste pipes shall be extended upward through the roof. 

(269), 



Sec, 3110 

or connected to vent stacks extended through the roof. Waste and soil 
stacks shall be extended through the roof and for the purpose of this sec- 
tion, the portion of a waste or soil stack above the highest fixture connected 
to it shall be considered a vent stack. 

(b) Vent pipes shall be connected at the bottom with a soil or waste 
pipe or with the building drain in such manner as to prevent accumulation 
of rust scale and properly to drip the water of condensation. The foot of all 
vent stacks shall be connected to soil or waste stack through a separate Y 
branch. 

(c) Vent stacks shall be extended to a height of not less than two feet 
above the roof and not less than one foot above the top of any window within 
fifteen feet. Where a roof is to be used for purposes other than weather 
protection, vent stacks shall extend not less than seven feet above the roof 
and the arrangement shall be subject to the approval of the commissioner. 

(d) No vent stack through roof shall be less than four inches in diameter 
from a point within the building. 

(e) Two or more vent pipes may be connected together but such con- 
nection shall be above the fixtures served. 

(f) Vent pipes shall not be connected to the trap or branched into the 
waste pipe except where a continuous vent is not practicable. Vent pipes 
shall be run as directly as practicable. Horizontal vent pipes when below 
the top of the fixture it serves shall be installed with the shortest possible 
horizontal run. The opening of these vents shall be above the center line of 
the waste pipe. 

(g) The size of a vent pipe, up to and including two-inch shall not be 
less in size than the outlet of the trap it serves. Such vent pipe shall connect 
to the waste pipe not more than eighteen inches from the trap. The size of a 
vent pipe shall not be less than as provided in the following table depending 
upon the number of fixture units which it serves and the length of the pipe. 



Pipe Sizes (Inches) 


Maximum Number 
of Fixture Units 


Maximum Length 
Feet 


11 


.5 

3 

25* 

100 

250 

500 

1250 

2400 


10 


1| 


25 


2" 


60 


3* 


125 


4" '..... 

5" 

6" 

8" 


250 

300 

400 

Not limited 







*Note exception below. 



In determining the length of a vent pipe the stack and branches shall be 
considered continuous. 

(270) 



Sees. 3111=3112 

(h) A vent pipe serving water closets, pedestal urinals, bed pan washers 
and service sinks shall not be less than two inches in size. Such two inch 
vent pipe shall not serve more than three fixtures of the above type and shall 
not be longer than forty feet. 

(i) The size of a vent stack shall be at least one half of the diameter of the 
waste or soil stack served. Where soil stacks are installed, fitted with con- 
nections for future use, are four inch in size, a parallel vent stack not less than 
three inch in size with three inch branches shall be installed. The parallel 
vent stack shall be connected to the soil stack below the lowest proposed 
fixture. 

(j) Where three or more vent stacks are connected near the top to a single 
pipe extending through the roof, the internal area of the combined stack shall 
be not less than one half the sum of the area of the stacks so connected. 

(k) Every vent pipe shall be free from dips or sags and shall be so graded 
and connected as to drip back to the soil or waste pipe. 

(I) Bow vents shall be installed only by permission of the commissioner 
and in accordance with his instructions and shall be dripped at its lowest 
point. 

[ *As amended by Ord. 1943, ch. 8 } 

jSect. 3111. Buildings More than One Hundred Twenty=Five Feet 
High. — (a) Vent stacks shall not be less than three inch in size. 

(b) Vent stacks serving water closets, pedestal urinals, bed pan washers 
or service sinks shall be increased to at least four inches in size at a point 
eighty feet above the bottom of vent stack. 

(c) Vent stacks shall not be connected to other vents or vent stacks but 
shall extend through the roof independently where practicable. 

(d) Vent stacks including the upper portion of soil or waste stacks, three 
inches in size shall be increased to four inch in size from a point below the roof. 

(e) 2" Branch vents serving water closets, pedestal urinals, bed pan 
washers and service sinks shall not be more than thirty feet long and shall 
serve not more than three of the above fixtures. Branch vents for other fix- 
tures shall comply with the table in section 3110. 

I -\As amended by Ord. 1943, ch. 8 ] 

JSect. 3112. Materials of Drainage System. — (a) Waste, soil and 
vent pipe shall be of cast iron hub and spigot pipe, cast iron screw pipe, 
galvanized steel or wrought iron, lead, iron size brass or copper, except that 
cast iron screw pipe, and galvanized steel or wrought iron pipe shall not be 
used underground. In buildings of Group I Occupancy galvanized piping 
shall not be used for built-in waste piping in floor or wall construction. 

(b) All sanitary and rain water drains within a distance of ten feet outside 
the inner face of the foundation wall shall be cast iron hub and spigot pipe 
coated with asphaltum or red lead. 

(c) Waste and vent pipes, traps and fittings serving fixtures in chemical 
laboratories or used for the disposal of acid or other corrosive chemicals shall 
be of approved acid resisting materials. The arrangement of piping shall be 
approved by the commissioner. All plumbing fixtures in large chemical 

(271) 



Sec. 3113 

laboratories shall have a separate system of drainage and vent piping inde- 
pendent of other drainage system of building. When diluting chamber is 
used individual vents for fixture traps in group fixtures may be omitted if 
main waste is extended through roof undiminished in size, and branch from 
main to fixture is not more than twenty-five feet. If branch waste to fixture 
is more than twenty-five feet the end of the branch shall be extended full size 
over roof or reconnected to main chemical vent stack. 

The effluent from diluting tank may waste into the building drainage 
system. 

The design and location of the dilution tank and arrangement of the piping 
shall be approved by the commissioner. 

[ %As amended by Ord. 1943, ch. S ] 

*Sect. 3113. Water Supply. — (a) All water piping of every descrip- 
tion supplying water from city mains to all plumbing fixtures and equipment 
with the exception of the distributing piping of hot water building heating 
system, intercommunicating piping between various pieces of apparatus 
of a boiler room plant, and engine room apparatus, shall be installed by a 
journeyman plumber licensed under chapter one hundred and forty- two of 
the General Laws under a permit issued to a registered and licensed Master 
plumber. 

(b) No water distribution system to pjumbing fixtures and equipment 
shall be installed until a plan submitted to the commissioner has been ap- 
proved for a safe and adequate supply. 

(c) Water supplied from city mains shall be distributed by a system of 
piping independent of water from any other source unless such source is 
approved by the health commissioner for drinking purposes. 

(d) No connections to fixtures supplied with city water, or to supply 
piping thereof, shall be made from other pipes, piping systems, mechanical 
apparatus, equipment or device, directly or indirectly, in such manner that 
in the opinion of the health commissioner, and the building commissioner, 
the quality of the potable water may be adversely affected. No plumbing 
fixture, device or construction shall be installed which will provide a cross 
connection between a distributing system of water for drinking and domestic 
purposes and a drainage system, soil or waste pipe or sprinkler or process 
piping system so as to permit or make possible the back flow of sewage or 
waste or non-potable water into the water supply either by gravity, siphonage 
or pressure. 

(e) The water service pipe and distribution pipes shall be of sufficient 
size to permit continuous ample flow of water to fixtures and equipment in 
all stories at all times. 

(f) Where the water pressure is insufficient to supply all fixtures freely 
and continuously a house supply tank or pneumatic system shall be provided, 
adequate for the purpose. Such tank or system shall be supplied by city pres- 
sure through automatic controls, where necessary by power driven pumps. 

(g) The over-flow pipe from gravity or house tank or drip pans shall be 
extended to drain into suitable plumbing fixture or be connected to rain 

(272) 



Sec. 31 13 

water leader. When connected to leader over-flow shall be fitted with deep 
seal trap and check valve. Over-flow pipe shall be at least twice the area of 
the water supply pipe feeding the tank. 

(h) All plumbing fixtures shall be provided with a sufficient supply of 
water for flushing to keep them in a sanitary condition. Every water closet 
and urinal shall be flushed by means of an approved flush valve or individual 
tank of at least four gallons flushing capacity for water closets and at least 
two gallons for urinals, and shall be adjusted to prevent the waste of water. 
The flush pipe for water closet flush tanks shall be not less than one and one 
quarter inches in diameter and the water from the flush tanks shall be used 
for no other purpose. 

(i) No plumbing fixture, mechanical apparatus, equipment or device 
shall be connected with building water supply distributing system through 
automatic flush valve, other valve or tank, unless such flush valve, valve or 
tank is located above the fixture or equipment being served. 

All water closets, urinals, slop hoppers, bed pan washers, dish washers 
and other fixtures receiving their supply of water through flush valves, shall 
have an approved type of vacuum breaker installed between flush valve and 
fixture or equipment being served. The vacuum breaker, shall be installed 
at a minimum distance of four inches from bottom of vacuum breaker to 
the top of fixture or equipment. 

Fixtures or equipment having water supplied through submerged inlets 
shall be fitted with an approved type of vacuum breaker installed in the 
water supply line between the water supply control valve and the fixture or 
equipment being served and at no less than four inches above the top of the 
device being served. 

All vacuum breakers shall be made easity accessible for observation, in- 
spection and repairs. 

For all fixtures and devices supplied through faucets or equivalent, such 
faucets shall be located above the top of the receptacle being served and with 
a minimum approved air gap between the end of supply nozzle and the top 
of receptacle. 

(j) An accessible shut-off shall be provided on the main water distribution 
pipe just inside the foundation wall which shall control the water supply 
to the entire building. In structures, other than residences occupied by one 
family, accessible shut-offs shall also be provided which shall separately 
control the water supply for each flat, apartment, suite, or store of a building. 

(k) Supply pipes of ferrous material shall not be installed under bath 
room floors in Group I occupancy. 

No pipe or fittings that have been used for other purposes, nor second 
hand pipe or fittings of objectionable origin shall be used for distributing 
potable water. 

(1) Water supply branch of lead, copper or brass to individual fixture 
shall not be less than three eighths inch size; of other material, not less than 
one half inch size. Water supply branch connected to a flush valve shall 
not be less than one inch size for water closet, pedestal or blow-out urinal 
and not less than one half inch size for other type of urinal. 

(273) 



Sees. 3113=3114 

Slip joints on water supply system shall not be used on the pressure side 
of fixture faucets or cocks. 

[ *As amended by Ord. 1943, ch. 8 ] 

fSect. 3114. Hot Water Supply. — (a) Hot water storage tanks 
shall be installed and connected by a licensed plumber under a permit issued 
to a registered and licensed master plumber . 

(b) No hot water storage tank or other vessel in which water is to be 
stored or heated under pressure shall be installed or connected unless there 
are plainly stamped thereon in the metal, the maker's business name, its 
capacity in terms of Massachusetts standard liquid measure, maker's guar- 
antee of pressure to which tank has been tested, maximum working pressure 
at which tank may be installed. The test pressure shall not be less than two 
hundred pounds hydraulic or hydrostatic pressure. The working pressure 
shall not be greater than forty-two and one half per cent of the guaranteed 
test pressure. No tank shall be installed at pressure greater than its working 
pressure. 

(c) Every hot water tank or boiler hereafter installed, or relocated to 
which a heating device or appliance is connected, in which water is to be 
heated under pressure above fifteen pounds per square inch, shall be equipped 
with pressure relief, temperature relief and vacuum relief valves placed in 
an accessible location. These valves are to be placed on the hot water tank 
or boiler, or on the piping to or from the hot water tank as hereinafter de- 
scribed. No make of such valves shall be used unless approved by the 
building commissioner. 

(d) Individual Pressure Relief Valves: Pressure relief valves shall 
have a disc which is kept closed by a spring on which tension can be varied 
to take care of different static pressures. The valve shall be set to open at a 
pressure not more than fifteen pounds higher than the working pressure 
stamped thereon in the metal of the tank or boiler. Valve may be placed 
on the hot or cold water supply above tank or boiler between control valve 
and tank or boiler. 

(e) Temperature Relief Valves: Fusible Plug Type: Temperature 
relief valves of the fusible plug type shall be placed in a separate tapping in 
the shell of the tank or boiler within twelve inches of the top of the tank 
or boiler, or on the hot water flow pipe from tank or boiler. Where tem- 
perature relief valve is installed on the flow pipe, it shall be within eight 
inches, developed length, from the top of the tank or boiler and the fusing 
element shall be installed within two inches of the flowing water. The 
fusing element of the individual temperature relief valve shall fuse and begin 
to discharge hot water from the tank or boiler when the temperature of the 
water has reached a point not greater than two hundred and twelve degrees 
Fahrenheit. 

(f) Temperature Relief Valves: Automatic Type: Temperature 
relief valves of the automatic type shall be placed in a tapping in the shell 
of the tank or boiler within twelve inches of the top of the tank or boiler, or 
shall be installed on the flow pipe from the top of the tank or boiler within 
eight inches, developed length, from the top of the tank or boiler and shall be 

(274) 



Sec. 3114 

installed within two inches of the flowing water, and shall begin to discharge 
hot water from the tank or boiler when the temperature has reached a point 
not greater than two hundred and twelve degrees Fahrenheit and shall close 
tight when the temperature of water in tank or boiler has been reduced 
approximately thirty-five degrees lower than the relief temperature. The 
capacity of the temperature relief valve shall be governed by the maximum 
heating rate of the hot water heater. A differential of ten degrees plus or 
minus from closing temperature will be considered satisfactory. 

(g) Vacuum Relief Valves: Vacuum relief valves shall be constructed 
so as to relieve vacuum instantly at a minus pressure not greater than one 
inch of vacuum in the tank or boiler. 

The relieving element of the vacuum valve shall be of materials that will 
not corrode or hold fast to the seat after prolonged use. 

The valve shall not leak under an internal pressure of from ten pounds 
to one hundred and twenty-five pounds per square inch. 

Valves of the ball check type shall not be approved. 

Vacuum relief valves shall be placed on the cold water supply pipe to tank 
or boiler above top of tank or boiler. 

Where cold water supply enters below the top of tank or boiler from a 
water supply located below the tank or boiler, the supply pipe shall rise to 
above the top of tank or boiler forming a loop and the vacuum valve shall be 
placed on top of loop above tank. 

(h) All internal parts of pressure relief valves, fusible plug valves or 
automatic relief valves shall be of materials impervious to corrosion equal 
to eighty-five per cent copper, five per cent tin, five per cent lead and five per 
cent zinc, except fusing element. 

(i) The casing of each valve shall be stamped, or have a metal strap 
attached to it stating in plain lettering the manufacturer's name, type of 
valve, limit of pressure relief settings, capacity of B. T. U. discharge and 
melting point of fuse plug. 

(j) Pressure relief, temperature relief valves shall have the discharge end 
of the valves extended to an open fixture or to the basement of the building 
near to the floor if open fixture is not available. 

(k) The valve shall be designed so that it will discharge water at a rate 
that will prevent any increase in the water temperature in the tank or boiler 
when the valve is in operation. 

(1) The area of the discharge pipe from the relief valves shall not be less 
than the area of the valve. When two or more valves are connected to the 
same discharge pipe the pipe area shall not be less than the aggregate area 
of all the valves it serves. The discharge pipe shall be of brass or copper 
and pitch down from the valve it serves to prevent the trapping of water. 

(m) Combination pressure and temperature relief valves may be used if 
they comply with all of the requirements as described for individual valves. 

Temperature relief of the fusible plug type or automatic type will be accept- 
able. 

(275) 



Sees. 3114=3115 

(n) In all hot water tanks or boilers having a capacity of one hundred 
gallons or larger the pressure relief valve shall be fitted with a lever type 
handle to allow for periodic tests by inspectors. 

(o) Tankless Hot Water Heaters: All tankless heaters connected to 
or part of heating boilers operated at more than five pounds pressure shall be 
equipped with approved type pressure relief valve. Pressure relief shall not 
be set more than one hundred and twenty-five pounds. Pressure relief valve 
shall be placed between control valve and heating coil, 

(p) Cistern Pressure Hot Water Tank: Cistern pressure hot water 
tanks in which water is to be heated or stored shall have an expansion pipe 
extended from the highest point of the hot water system or from the top of 
the hot water tank, over the top of the supply tank that supplies the water 
to the hot water tank. No valve of any description shall be installed on 
the expansion pipe between the top of the hot water tank and its opening 
above the supply tank. The expansion pipe shall be of non-ferrous material. 

(q) No check valves or non-by-pass pressure regulators shall be installed 
on the cold water supply to the hot water tank. 

(r) When check valve or pressure regulator is installed the installation 
shall be approved by the Commissioner. 

(s) No shut off valve shall be installed to prevent the circulation of water 
between the hot water tank and its heater, unless approved by the Com- 
missioner. 

[ ]As amended by Ord. 1943, ch. 8 ] 

JSect. 3115. Plumbing Fixtures and Units. — (a) The orifice of the 
jet of every drinking fountain shall be placed above the rim of the fixture and 
shall throw an inclined stream. The water supply issuing from the orifice i 
shall be of sufficient volume and height so that persons using the fountain 
need not come in direct contact with the orifice. 

(b) Earthenware integral fixture traps shall have a flange on the fixture 
bolted to a flange on the end of the waste or soil pipe, the joint made tight 
with red or white lead or other approved compound, or with an approved 
gasket. A rubber gasket shall not be used. If the waste or soil pipe is of 
lead the flange on its end shall be of heavy brass soldered to the lead pipe; 
if of cast iron, the flange shall be of extra heavy cast iron caulked or screwed 
to the pipe. Such floor flanges for water closets, slop sinks or urinals shall 
be not less than three sixteenths inch thick. The joint between flange and 
lead bend or start shall be examined by the Plumbing Inspector before the 
fixture is permanently set. 

The waste or soil pipe to floor or wall outlet earthenware fixtures where 
used with a flange shall terminate at the finished floor or wall line. 

Brass floor or wall flanges shall be of heavy pattern with no openings 
except for bolts and waste openings. 

Lead closet bends or starts shall be limited to one connection, which shall 
be used for vent only, except in replacement of the closet bend or start existing 
wastes may be connected to new bend or start. 

The lead bend or start shall be connected to the drainage system by means 
of a heavy bell shaped brass ferrule with full size wiped solder joint. 

(276) 



Sec. 3115 

(c) No trough or multiple type urinal or water closet shall be installed 
except for exterior temporary use, unless approved by the commissioner. 

(d) Minimum size of floor drain shall be 3" except as noted for refrig- 
erator wastes in table below. 

(e) The following schedule shall be used for determination of the minimum 
diameters of fixture traps and the equivalent unit of value. 



Fixture. 



Trap Size 
(Inches.) 



Unit 
Value. 



Bath Room Group — 1 W. C. — 1 Lav. — 1 Bath Tub 

Bath Room Group -1W.C.-1 Lav. — 1 Bath Tub — 1 Shower Stall 

Baby's Bath Slab 

Bed Pan Sterilizer 

Bed Pan Washer 

Combination Sink and tray 

Commercial laundry tray — Revolving type — 1\ gallon per minute 
discharge 

Dish washer — Hotel — Restaurant — Club 

Dental Cuspidor 

Drinking Fountain 

^loor Drain — Unrated Fixtures — for each gallon per minute discharge 

Floor Drain — For Refrigerator Wastes — Minimum Trap Size 2" 

Foot Bath 

Instrument Sterilizer 

Laundry Tray 

Lavatory 

Pedestal Urinal 

Bar Sink 

Fish Sink 

Kitchen Sink 

Kitchen Sink — Hotel — Restaurant — Club 

Laboratory Sink 

Lunch Counter Bar Sink — Combination of Same 

Pot Sink 

Scullery Sink — Hotel — Restaurant — Club 

Sewage Ejectors — For Each 25 Gallons per Minute Discharge 

(277) 



3 
3 



6.0 
7.0 
2.0 
5.0 
5.0 



2.0 



4.0 



H 



6.0 
0.5 
0.5 



14 



2.0 
0.5 
2.0 



U 



0.5 



1§ 
14 



2.0 
1.0 



5.0 



U 


2.0 


2 


4.0 


14 


2.0 


2 


4.0 


1 1 


2.0 


2 


4.0 


2 


4.0 


2 


4.0 




50.0 



Sees. 3115=3116 



Fixture. 



Trap Size 
(Inches.) 



Unit 
Value. 



Shower Stall 

Slop or Service Sink — Group H and I Occupancy 

Slop or Service Sink 

Stall Urinal 

Surgeon's Sink 

Restaurant Glass Sink 

Restaurant Silver Sink 

Vegetable Sink — Hotel — Restaurant — Club. . . 

Wall Hung Urinal 

Water Closet 

Water Still 

Utensil Sterilizer 



2 
2 
3 
2 

n 

2 



4.0 
4.0 
5.0 
4.0 
2.0 
2.0 
2.0 
4.0 



H 



4.0 
5.0 
0.5 



11 



0.5 



Unit value of fixtures not contained in the above table shall be determined by the commissioner. 

[ | As amended by Ord. 1943, ch. 8 and Ord. 1955, ch. 2 ] 

*Sect. 3116. Cast Iron Pipe. — (a) Cast iron pipe shall be sound, 
cylindrical and smooth, free from cracks, sand holes and other defects, of 
uniform thickness and of the grade known in commerce as extra heavy. 
If buried underground it shall be coated with asphaltum or red lead; otherwise, 
it shall be uncoated until inspected and approved. The weight of cast iron 
pipes per length, in lengths to lay five feet, shall not be less than listed in 
the following table: 



Minimum Weights of Cast Iron Pipe. 





Diameter (Inches) 


Weight 


per 


Length 


(Pounds) 




Single Hub. 


1 Double Hub. 


2 


25 

45 

60 

75 

95 

150 

215 

270 

375 




26 


3 


47 


4 


63 


5 


78 


6 


100 


8 


157 


10 


225 


12 


285 


15 


395 







(278) 



Sec. 3116=3117 

(b) Fittings for cast iron hub and spigot pipe shall be of the weight 
known in commerce as extra heavy and shall comply with the weights and 
dimensions to the cast iron soil pipe fittings as approved by American Stand- 
ards Association. 

(c) Joints in cast iron hub and spigot pipe shall be made with hemp or 
oakum and molten lead run full and caulked to make gas and water tight 
without the use of wax or any compound. 

(d) No double hub or sleeve shall be used on cast iron drain, soil, waste, 
or vent pipes. The drilling, tapping or welding of cast iron, hub and spigot 
drain, waste, soil or vent pipes, and the use of saddle hubs or bands are 
prohibited. 

(e) Caulking ferrules shall be of approved quality bell shaped cast brass, 
not less than four inches long and not less than diameter and weight listed in 
the following table: 

Minimum Diameter and Weight of Cast Brass Ferrules. 



Diameter (Inches) 


Weight (Ounces) 


2\ 


16 


Z\ 


28 


4| 


40 







(f) Cleanouts in cast iron hub and spigot pipe shall have brass or iron 
bodies. Cleanouts shall be the full size of the pipe up to four inches and 
not less than four inches for larger pipes. The caps shall be of cast brass not 
less than one quarter inch thick, shall have square or hexagonal nuts not 
less than three quarter inch high and one and one half inches in least diameter, 
or recesses for special wrenches, and shall have not less than six tapered 
threads standard for iron pipe. Caps as described above shall also be used 
for cleanouts in screw pipe drainage systems. 

(g) Where steel or wrought iron pipe, two inches or less in diameter, is 
connected to cast iron hub and spigot pipe the joint shall be made by means 
of an approved caulking sleeve or fitting. 

(h) Caulking hubs when used on screw pipe shall be heavy pattern. 
Caulking sleeves shall not be used as hubs. 

[ *As amended by Ord. 1948, ch. 8 } 

fSect. 3117. Wrought Iron and Steel Pipe. — (a) Galvanized 
wrought iron or galvanized steel pipe shall be of not less than the following 
thickness and weight per linear foot: — 



(279) 



Sees. 3117=3118 



Size 


Diameter 


(Inches) 


Thickness 
(Inches) 


Weight Per Foot 

(Pounds) 

Plain Ends 


External 


Internal 


\i 


.675 
.840 
1.050 
1.315 
1.660 
1.900 
2.375 
2.875 
3.500 
4.000 
4.500 
5.563 
6.625 
8.625 
10.750 
12.750 


.493 

.622 

.824 

1.049 

1.380 

1.610 

2.067 

2.469 

3.068 

3.548 

4.026 

5.047 

6.065 

8.071 

10.136 

12.090 


.081 
.109 
.113 
.133 
.140 
.145 
.154 
.203 
.216 
.226 
.237 
.258 
.280 
.277 
.307 
.330 


0.567 


}/£ 


0.850 


% 


1 . 130 


1 


1.678 


1J4 


2.272 


\y 2 


2.717 


2 


3.652 


2y 2 


5.793 


3 


7.575 


3H 


9.109 


4 


10.790 


5 


14.617 


6 


18.974 


8 


24.696 


10 


34.240 


12 


43.775 







(b) Nipples when used shall be cut from standard weight pipe. 

(c) Fittings for wrought iron or steel soil, waste or drain piping shall be 
cast iron, recessed and threaded drainage fittings, with smooth interior 
water-way and threads tapped so as to provide a uniform slope in branches 
from vertical pipe of not less than one quarter inch per foot. Fittings for 
wrought iron or steel vent piping shall be cast pattern. 

(d) All screw pipe used for soil, waste and vent shall be reamed to eliminate 
burr. 

[ ]As amended by Ord. 1943, ch. S ] 



JSect. 3118. Brass, Copper and Lead Pipes. — (a) Brass and copper 
pipe for soil, waste and vent pipes shall be of the weight and thickness known 
in commerce as iron pipe size. 

(b) Fittings for brass or copper soil, waste or drain pipes shall be recessed 
heavy cast brass or cast iron drainage fittings with smooth interior water-wajr 
and iron pipe size threads tapped so as to provide a uniform slope in branches 
from vertical pipes of not less than one quarter inch per foot. 

(c) Lead pipes for soil, waste and vent pipes including bends and traps, 
shall be not less than the following average thickness and weight per linear 
foot and not more than the following lengths: 

(280) 



Sees. 3118-3119 



Size (Inches) 


Thickness 
(Inches) 


Weight per 

Linear Foot 

(Pounds) 


Maximum 

Lengths 

(Feet) 


1J 


1/8 

1/8 

1/8 

9/64 

11/64 

5/32 


2.50 
3.00 
4.00 
5.00 
8.00 
10.00 


6 


1§ 


10 


2 


10 


2\ 


10 


3 


4 


4 


4 







(d) The use of lead pipes In a drainage system is restricted to the above 
table. Concealed horizontal lines of lead pipe shall be supported for their 
entire length. All other lead pipes shall be properly supported to prevent 
sagging. 

(e) Branch connections of lead pipe shall be full size wiped solder joints; 
connections of lead pipe to cast iron and screw pipe shall be made by means 
of brass ferrules and soldering nipples respectively to which the lead pipe 
shall be full size wiped solder joints, other connections in lead pipe shall be 
made by means of a round or flanged full size wiped solder joint. Overcast 
or cup joints are prohibited. 

(f ) Soldering nipples for the connection of lead pipe to screw pipe shal 1 
be of approved quality cast brass or of brass pipe, iron pipe size. If cast, 
they shall have not less than the weight listed in the following table: 

Minimum Weights of Cast Brass Soldering Nipples. 



Diameter (Inches) 



Weight (Ounces) 



11 


8 


2 


14 


2\ 


22 


3 


32 


4 


56 







[ %As amended by Ord. 1943, ch. 8 



*Sect. 3119. Hangers and Supports. — Drainage System: All drain, 
waste and vent piping shall be securely supported with approved metal 
hangers or supports, in such a manner as to prevent sagging or swaying. 

Drainage piping placed in filled ground or other shifting soil shall be securely 
hung from the building structure by brass rod of approved diameter and rust 
proof hangers. 

(281) 



Sees, 3119=3121 

Drainage piping placed in filled ground or other shifting soil outside or 
inside the building structure, shall be properly supported in such manner as 
to prevent settling of the pipe. 

Vertical stacks shall be supported at each floor. 

Horizontal lines shall be supported at approximately five feet on centers 
when of calked lead joint construction and approximately eight feet on 
centers when of screw pipe construction. 

Inserts for concrete construction shall be of malleable iron, cast iron or 
pressed steel. When pressed steel is used it shall be rust proof and not less 
than twelve gauge. 

Expansion shields when used shall be of an approved type. 

Friction clamps when used shall not be made of less than one and one 
quarter inch by one quarter inch stock. 

Three eighth inch rod shall be the minimum size used. 

Rod sizes, when used with band or ring type hanger, shall be as follows: 
piping up to and including two inch in size, three eighth inch, piping two 
and one half inch and up to and including six inch in size, one half inch 
piping above six inch in size five eighth inch. 

Hangers consisting of rod only shall be in the U form and both ends of the 
U shall be fastened to the structure, and of sizes called for above. 

Water Supply Piping: All water supply piping shall be securely supported 
with approved metal hangers or supports, in such a manner as to prevent 
sagging or swaying. 

Wire hangers shall not be used for supporting pipes larger than one inch 
in size. When wire hangers are used the wire shall be not less than one eighth 
inch gauge. 

Horizontal lines of pipe shall be supported as follows: pipes one quarter 
inch and up to one half inch in size, approximately eight feet on centers and 
pipes three quarter inch or larger approximately ten feet on centers. 

Vertical lines of water supply piping shall be properly supported. 
[ *As amended by Ord. 1943, ch. 8 ] 

fSect. 3120. Inspection and Tests. — (a) No part of a plumbing 
system shall be covered or concealed from view until it has been examined 
by the plumbing inspector or tested in the presence of a plumbing inspector 
and approved by the commissioner, who shall examine or test it within two 
working days after receiving written notice that the work is ready for inspec- 
tion, weather permitting. No part of a plumbing system shall be used unless 
the drain, soil, waste, vent and the water supply pipes, when roughed in, 
have been tested by the plumber in the presence of the plumbing inspector 
as hereinbefore provided at a time when such test is practicable. 

(b) Tests shall be made by water if practicable, or air pressure in such a 
manner as to disclose all leaks and imperfections in the work. 
[ \As amended by Ord. 1943, ch. 8 ] 

JSect. 3121. Prohibited Fixtures, Fittings and Connections. — 

The following list of fixtures, fittings, connections, and devices are hereby 
prohibited: 

(282) 



Sec. 3121 

Fixtures: Submerged flushometer closets. 

Second hand fixtures of objectionable origin, unless approved 

by the commissioner. 
Unlined wooden sinks or trays for restaurants and laundries. 
Long hoppers. 

Enameled iron water closets and urinals. 
Wash sinks or basins so fitted as to retain water to be used 
simultaneously by more than one person. 
Fittings: Double hubs. 

Sleeves used as hubs. 
Saddle hubs and bands. 
Repair clamps. 
Connections: Slip and union joints on sewer side of trap. 

Drilling or tapping of drain, soil, waste or vent pipes. 
Devices: Traps depending on partitions to form seal. 

Iron bath traps up to two inch. 
Water jacketed grease traps. 
Fire pot hot water generators except on gravity supply hot 

water systems. 
Three quarter and full S traps under three inch in size. 
No trap or water supply piping shall be exposed to freezing 
without adequate protection. 

[ %As amended by Ord. 1943, ch. 8 ] 



(283) 



Sees. 3201=3301 



PART 32. 
VALIDITY. 

Section 3201. The invalidit}^ of any section or provision of this act shall 
not invalidate any other section or provision hereof. 



PART 33* 

WAR PROVISION. 

Section 3301. During the continuance of the existing state of war 
between the United States and certain foreign countries, and for the period of 
six months following the termination of such existing state of war, the Build- 
ing Commissioner may grant a permit allowing the substitution of specified 
building materials and methods of construction for the materials and methods 
now required by this code, whenever he shall find that the materials required 
by the code are not available or cannot be obtained because of a Federal 
law, rule, or regulation, and that the substitution shall not conflict with the 
spirit and intent of this code. 

[*As inserted by Ord. 1943, ch. 9] 



(284) 



Sees. 1-5 



GASFITTING REGULATIONS. 



Consistent with the provisions of chapter 479, Acts of 1938 as amended, 
known as the Boston Building Code and hereinafter referred to as the Code, 
the building commissioner of the city of Boston and the health commissioner 
of the city of Boston in joint meeting this 22d day of June, 1943, hereby 
establish regulations governing work performed or to be performed and 
materials used in gasfitting in all buildings and structures in the city of 
Boston which are subject to the provisions of the above mentioned chapter 
as amended. 

Said regulations known as City of Boston, Massachusetts, Gasfitting 
Regulations are as follows: 

License Required 

Section 1. All gasfitting in buildings shall be done by licensed master 
gasfitters, either by themselves or through licensed journeyman gasfitters 
employed by them as stated in Section 121 of the Code. The words "master 
gasfitter" and the words "journeyman gasfitter" as used in these regulations 
shall apply to persons licensed as master gasfitters and journeyman gasfitters 
as provided in Section 121 of the Code. Persons desiring a master gasfitter's 
license must possess a journeyman gasfitter's license before they can be eligible 
for examination or registration as a master gasfitter. The fee for issuance or 
renewal of a master or journeyman gasfitting license shall be as provided in 
paragraph (e), Section 121, of the Code or as changed by the building com- 
missioner with the approval of the mayor. 

Application for Permits, Permits and Fees 
Section 2. Whoever desires in the city of Boston to install, alter or 
repair any gasfitting system shall first make application to the building 
commissioner, pay fee and obtain a permit therefor as provided for in Sec- 
tions 110, 111 and 112 of the Code. Permits for gasfitting shall not be granted 
to any person other than a licensed master gasfitter. 

Definition of Gasfitting 

Section 3. Gasfitting shall mean the work of putting together any fit- 
tings, pipes or fixtures or other appliances which are to contain gas for heat,, 
light, or power purposes and shall be subject to inspection under existing, 
laws. 

No Pipe or Fitting to be Concealed Until Approved 

Section 4. No pipe or fitting shall be covered or concealed from view 
until approved by gasfitting division of the building department. 

Final Test 

Section 5. There shall be a final test, by a gasfitter, of all fixtures and' 
pipes by a column of mercury raised not less than two inches, which must 

(285) 



Sees. 5=8 

stand five minutes; this test to be made in the presence of one of the gas- 
fitting inspectors of the building department; the gauge to be made of tubing 
of uniform interior diameter, and so constructed that both surfaces of the 
mercury will be exposed to view. 

Gas Not to be Turned on Until Piping and Fixtures Approved 
Section 6. Gas shall not be turned on in any building until the piping, 
appliances and fixtures have been approved by the building commissioner. 

Relative to the Maintenance and Repairs of Gas Piping, Fixtures and 

Appliances 

Section 7. The building commissioner may condemn and order the 
removal, reconstruction or replacement of any system of gas piping, fixtures 
or appliances, or portions thereof, which in his opinion is so constructed or 
installed as to become hazardous to life or property. He shall order the 
necessary repairs to be made when defects are found in any system. 

Upon notice by the building commissioner gas companies supplying gas in 
the city of Boston shall immediately discontinue the supply of gas in any- 
building where a dangerous or hazardous condition exists due to a faulty 
system. Re-entry of the supply of gas into a system shall not be permitted 
until so ordered by the building commissioner. 

Service to Buildings 

Section 8. Every building shall have an independent service from the 
street unless in the opinion of the building commissioner this is found 
impractical. 

The extension, however, of a gas service if not less than one and one half 
inches in diameter laid under ground and properly graded, may be permitted 
from a building located on the front portion of a lot to a garage, workshop 
or a building of a similar character located in the rear of said lot or a group 
of buildings connected by pipe ways or tunnels, and owned by the same party. 

Every service pipe shall be fitted with a beaded malleable tee placed as to 
be easily opened to clear the service pipe or any stoppage. 

The unused outlet (opposite the service) of this tee must be fitted with a 
one half inch nipple and cap. The side outlet of the tee must be fitted with 
a street ell or nipple and ell and service gas cock. 

When service pipes are over two inches in size brass composition seated 
gate valves shall be used. 

All main or service cocks and gate valves shall be kept readily accessible 
for emergency operation or repairs. 

Pressure Regulators to be Vented 

In cases where it is necessary to reduce the pressure of gas at the meter by 
means of a pressure regulator, or governor, which requires access to the 
atmosphere for successful operation, the regulator, or governor, shall be 
equipped with a vent pipe leading to the outer air. The end of this vent 

(286) 



Sees. 8-9 

pipe shall terminate not closer than five feet to any window or door opening. 
Means shall be employed to prevent water from entering this pipe and also 
to prevent stoppage by insects or foreign matter. 

Gas Meters and Locations 

Section 9. Gas meters shall be so located as to be readily accessible for 
examination, reading and replacement. Meters shall not be set above the 
basement or cellar and shall be located as near the service as practical, except 
on the approval of the building commissioner. No meters shall be installed 
in bedrooms, elevator shafts, or in any confined space. No meter shall be 
installed in any location where it will be subject to damage or corrosion, or 
where it will be subject to extreme temperature changes. No gas meters 
shall be located closer than five feet "measured horizontally" to any electric 
meter or other electric appliance capable of producing an arc. 

On all installations requiring more than 1,800 cubic feet per hour, dual 
meters may be required. Gas company approval of the meter layout should 
be received before starting the work. 

Where dual meters are installed they shall be sized so that one meter 
shall have a capacity of at least sixty per cent of the connected load. 

All meters larger than the 100-light size shall be flange connected. 

The gas company will install a meter of adequate size only on the approval 
of the piping from the gasfitting division of the building department. 

No sub-meters shall be installed unless the piping has been approved by 
the gasfitting division of the building department. 

No person shall remove any gas meter from the premises except the duly 
authorized representative of the gas company owning such meter. 

Meter Connections 

There shall be a service cock at the inlet side of each meter. When piping 
to the meter is over two inches brass composition seated gate valves shall be 
used. 

The size of meter connections shall be determined by the piping scale. See 
Section 11. 

Ail meter connections up to and including the 100-light size are to be made 
with rigid iron connections of a type approved by the building commissioner, 
and shall be held in alignment by double swing elbows on the inlet and outlet 
of meter connections. 

Meters shall be adequately supported and connected to the piping so as 
not to exert undue strain on the connections. 



Size. 
5-Light 
10-Light 
20-Light 
30-Light 
60-Light 
100-Light 



Size of 
Iron Pipe. 


Width Between 

Center of Tubes 

and Face 

of Flanges. 


Height to Top 
of Tube Screws 
Center Flanges. 


3// 
4 


Ill" 


1'- 4«/ie" 


1" 


1'- If" 


1'- Qh" 


11" 


1'- 4" 


l'-lO" 


11" 

1 2 


1'- 6|" 


2'- 2" 


2" 


2'- If" 


2'- 7f" 


2" 


2'- 5i" 


3'- 31" 



Depth from 
Center of Tube 
Center Flanges 
Back of Meter 

4f" 



< 2 

10" 



r 



i" 

a 



(287) 



Sees. 9-10 

Steel Case Meters — Tapered Thread Side Connections 

Size. Size of Pipe. Width. Connections. Depth. 

No. 4§ 4" 31" 25f" 8 27 /32" 

No. 5 4" 37" 32f " 10£" 

Height Over All 

No. 4f B'-^W 

No. 5 4'-3|" 

Meter Capacity 

5-Light 110 cubic feet per hour 

5-Light B 150 cubic feet per hour 

10-Light 210 cubic feet per hour 

10-Light B 300 cubic feet per hour 

20-Light 330 cubic feet per hour 

20-Light B 450 cubic feet per hour 

30-Light 400 cubic feet per hour 

30-Light B 600 cubic feet per hour 

60-Light GOO cubic feet per hour 

60-Light B 1,250 cubic feet per hour 

100-Light 900 cubic feet per hour 

100-Light B 1,800 cubic feet per hour 

No. 4| Steel Case 3,000 cubic feet per hour 

No. 5 Steel Case 5,000 cubic feet per hour 



BUILDING PIPING 
Material of Pipe and Fitting Standard Full Weight 

Section 10. All gas pipes shall be of standard full weight wrought iron or 
steel; all fittings of malleable iron, except above two inches when cast iron 
if not concealed will be allowed; all joints shall be made with red and white 
lead or other approved material. No gasfitter's cement shall be used except 
in putting lighting fixtures together. 

No second-hand pipe shall be put into use in any building without the 
written permission of the building commissioner. 

No pipe shall be laid so as to support any weight (except lighting fixtures) 
or be subject to any strain whatever. 

No pipe shall be embedded in the required fireproofing of columns or other 
structural members. 

No pipe shall be installed in an elevator shaftway. No pipe shall be laid 
in ash or cinder fill. 

No pipe shall be laid within six inches of any electric wire except where 
the electric wire is in conduit. 

The supply line to pilots used for heating or power boilers shall be run 
overhead and shall not be installed in any floor construction or in any place 
exposed to extreme cold, and in no case shall such supply line be less than 
one half inch pipe. 

(288) 



Sec. 11 

Bracket fixture-outlets shall not be placed closer than two inches to window 
or door casings or back of doors; within three feet under any overhead shelving; 
or within three feet, measured horizontally, of any gas meter. 

Pipes laid in a cold or damp place shall be properly dripped, painted with 
two coats of red lead and boiled oil or covered with felting satisfactory to 
the building commissioner. 

In concealed work, above the basement, the piping in Type IV and Type 
VI buildings shall be laid above the timbers. 

No gas pipes shall be let into any timbers, beams, or girders more than 
two inches, and shall be placed within thirty-six inches of the end of said 
timbers, beams or girders. 

Fixture ceiling outlet drops shall be fitted in the piping above with a tee, 
and a pipe must be run not less than four inches longer or to a bearing and 
be capped and securely fastened on both sides of the tee. 

Fixture wall outlets may terminate with an ell and must be fastened with 
two clips on the riser. Outlets for fixtures and risers shall extend not more 
than one inch through ceiling or wall and when not in use left capped. 

All piping shall be constructed and installed so as to make a durable and 
substantial system of a size and so installed as to provide a supply of gas 
sufficient to meet the maximum demand without undue loss of pressure 
between the street and the fixtures or appliances. 

When necessary to cut out pipe for extension or repair, pipes shall be put 
together with right and left couplings and in no case shall unions or running 
threads be permitted. 

Fastening Pipes 

Only such metal pipe strap, iron hooks, hook plates or hangers suitable 
for the size of pipe to be secured and of standard strength and quality shall 
be used for supporting pipes. 

The following is a maximum spacing of supports which shall be used in 
continuous piping installations: 

| inch or § inch pipe 6 feet 

| inch or 1 inch pipe 8 feet 

1| inch or larger (horizontal) 10 feet 

1| inch or larger (vertical) 2 every floor level 

Piping Size Requirements 
Section 11. Maximum length of run permitted — Flow of Gas — Cubic 
Feet Per Hour. 



(289) 



Sec. 12 

Normal Pipe Size 

(Fel5'|-In.Hn. f-In. 1-In. l|-In. lj-ln. 2-In. 2£-In. 3-In. 4-In. 6-In. 

10 55 110 315 630 1100 1740 3630 6330 10100 20550 56800 

20 40 80 220 475 800 1265 2680 4590 7275 15000 39550 

30 — 65 190 380 665 1100 2050 3800 5850 12330 32900 

40 — — 160 315 570 950 1740 3160 5060 10430 28400 

50 — — 145 285 505 790 1580 2850 4590 9490 25900 

60 — — — 270 475 725 1580 2690 4110 8540 23700 

70 _ _ _ 235 430 695 1425 2370 3790 7900 21650 

80 — — — — 400 630 1265 2215 3640 7430 20400 

90 — — — — 380 600 1265 2215 3480 7110 19100 

100 — — — — 365 555 1100 2055 3160 6640 18150 

125 — — — — — 520 1100 1900 3000 6160 16250 

150 — — — — — 475 950 1740 2690 5525 14860 

175 — — — — — — 950 1580 2530 5210 13900 

200 — — — — — — 790 1425 2210 4740 12970 

250 — — — — — — — 1265 2055 4270 11370 

300 — — — — — — — 1100 1900 3790 10580 

350 — — — — — — — — 1740 3480 9640 

400 — — — — — — — — 1580 3320 9000 

450 — — — — — — — — 1380 3160 8530 

500 — — — — — — — — — 3000 8210 

Approximate Demands for Types of Gas Appliances 
Section 12. The size of gas pipe to be installed in any installation 

depends on the maximum gas consumption of the appliance to be connected 

and the length of the pipe and number of fittings. 

The demand of appliances in cubic feet per hour should be determined 

by dividing the manufacturer's B. t. u. rating of the appliance by the heating 

value of the gas (528). 

For the guidance of the fitter, when the rating is unknown, the following 

approximate maximum demands for some common gas appliances are given: 

Demand 
B. t. u. Cubic Feet 

Per Hour. Per Hour. 

Domestic gas cooker (Three-Burner Top) 37,100 70 

Domestic gas range (Four-Burner Top) 55,000 105 

Domestic gas range (Six-Burner Top), extra oven. . . . 104,000 195 

Domestic range with kitchen heater 83,000 155 

Domestic hot plate or laundry stove, per burner 9,000 17 

Space heater, radiant, per radiant 1,875 3| 

Space heater, luminous flame, per top 1,325 1\ 

Outlet for lighting bracket 5,300 10 

Gas steam radiator, per section 2,120 4 

Gas log 13,250 25 

Dental Bunsen, curling iron 1,325 2\ 

Hotel range, per section 116,600 220 

Restaurant range 106,000 200 

Confectioner's stove 66,250 125 

Domestic circulating tank water heater 21,200 to 37,100 40-70 

Domestic automatic storage water heater (20 gallons), 18,550 35 

Domestic automatic storage water heater (45 gallons), 42,400 80 

(290) 



Sec. 13 

Automatic Instantaneous Water Heaters 

(Gas line to be run full size of inlet of heaters) 

Capacity 2§ gallons per minute 95,400 180 

Capacity 3 gallons per minute 116,600 220 

Capacity 4 gallons per minute 143,100 270 

Capacity 6 gallons per minute 212,000 400 

Capacity 8 gallons per minute 291,500 550 

Gas-fired boiler, per horse power 47,520 90 

Gas engine, per horse power 21,200 40 

Definitions 

B. t. u. — The British thermal unit is the quantity of heat required to 
raise the temperature of one pound of water one degree Fahrenheit. 

Specific Gravity — Specific gravity is the ratio of the weight of a given 
volume of gas to that of the same volume of air. 

Gas pressure is measured by the height of the water column, in inches, it 
will support. 

Appliances and Appliance Installations 

Section 13. Except as otherwise provided for in these regulations, no 
appliance shall be installed unless it meets the requirements of safety and 
service, established by an approved representative organization such as the 
American Gas Association Testing Laboratory, the American Society of 
Mechanical Engineers or other recognized authorities. 

In the case of appliances of a type on which no such requirements have 
been established, the building commissioner may require tests of the appli- 
ances and on the results of these tests shall determine whether or not the 
appliance shall be installed. 

Appliances shall be installed so that their continued operation shall not 
in any way create a hazard to persons or property. 

No appliances shall be installed in a room in which the normal conditions 
for ventilation do not permit the proper combustion of the gas under normal 
conditions of use. 

No appliance shall be installed which is not easily adjusted or readily 
cleaned, and whose adjustable parts, such as air shutters and orifices, do not 
remain securely fixed in any desired position. 

No device or attachment shall be installed in any piping or on any appli- 
ance which may in any way impair the combustion of the gas. 

A gas cock or shut-off, which constitutes the means of gas control, shall be 
easily accessible and within convenient reaching distance when lighting the 
burner. 

All appliances shall be connected with a right and left coupling and a 
master cock to the house piping. Gas refrigerators may be connected with 
one-foot length of copper tubing with swadged joints and union in place of a 
right and left coupling. 

Cocks controlling several appliances or lighting fixtures shall be placed 
at an adequate distance from each other so that they will be readily distin- 
guishable — this distance to be not less than six inches. 

(291) 



Sec. 13 

Appliances equipped with a control cock or cocks shall not be connected 
with rubber or flexible tubing. 

When air or oxygen under pressure is used in connection with the gas 
supply, effective means such as a check valve for air and a relief trap for 
oxygen of an approved type shall be provided to prevent the air or oxygen 
from going back into the gas pipe. 

Every flue-connected appliance (except an incinerator), unless its con- 
struction serves the same purpose, shall be equipped with an effective back- 
draft diverter. If the draft hood is the cone type, it must be installed in a 
vertical position adjacent to the appliance. The flue pipe of dual -oven 
ranges shall be equipped with a fly damper installed in a horizontal position. 

No gas appliances shall be installed in locations where their continued 
operation will raise the temperature of surrounding combustible material, 
including woodwork, more than 90 degrees Fahrenheit from a normal tem- 
perature of the room unless adequate protection is provided. 

No space heater shall be installed in any room or place where its operation 
would cause a hazard to persons or property. 

Individual fixed heating appliances, which include gas-fired steam radiators, 
hot air radiators, gas logs, gas mantles, radiant fires and similar types of 
appliance, shall be connected with rigid iron pipe to the house piping. 

Portable gas heater, which includes many miscellaneous types of small 
heaters for temporary or quick heat, when constructed to meet the minimum 
requirements of safetj^ and service and without a controlling cock on the 
heater may be connected with flexible tubing; only approved quality tubing 
of not more than an eight-foot length with the controlling cock at the house 
piping will be permitted. 

Any floor, wall or ceiling which is constructed wholly or partially of wood 
or combustible material, or is of such construction that the temperature main- 
tained will cause deterioration of material, shall be regarded as combustible. 

No range, oven or other appliance of the hotel or restaurant type shall be 
installed on a combustible floor unless raised to provide an air space of at 
least four inches between the bottom of the appliance and the combustible 
floor. The combustible floor beneath the appliance shall be given protection 
as effective as: 

(1) A sheet of asbestos one-half inch thick laid beneath No. 26 gauge gal- 
vanized metal extending six inches beyond the appliance and an intermediate 
baffle consisting of a sheet of asbestos one-half inch thick between two sheets 
of No. 26 gauged galvanized metal held in place half way between the bottom 
of the appliance and the floor; or 

(2) Terra cotta blocks, with the cells arranged to provide continuous air 
spaces, placed over a sheet of asbestos one-half inch thick laid beneath No. 26 
gauge galvanized metal extending six inches beyond the appliance, and 
covered with three-eighths inch of boiler plate. 

The air space required above may be omitted provided eight inches of 
brick or concrete is placed between the bottom of the appliance and the 

floor. 

Every hotel and restaurant type range shall have erected over it a hood 
adequate in size to receive the products of combustion from the appliance. 

(292) 



Sees. 14=16 

The hood is to be vented through a masonry chimney, or by a metal duct 
and fan, to the outer air. 

The owner or his agent must receive a permit for the installation of gas- 
fired house heating boilers and furnaces, bake and industrial ovens, power 
boilers, gas engines, and if existing appliances are converted to gas fuel 
irrespective of the gasfitter's permit for performing the work. 

Kitchen Regulations 
Section 14. No domestic gas stove or appliance for cooking shall be 
installed in a room which does not meet the requirements of the Code. Every 
kitchen, kitchenette, or room adapted for cooking purposes shall be not less 
than the minimum dimensions established by the Code. Ventilation of 
every such room shall be in compliance with the provisions of the Code. 
Interior kitchens or kitchenettes, provided with mechanical ventilation, 
shall be in continuous operation while range is lighted and the door to kitchen 
or kitchenette shall have bottom panels removed and louvres of wire mesh 
screen not less than one quarter inch mesh installed in place of panels. 

Installation of Fuel Oil, Coke, Gas and Electric Ranges 

Commercial and domestic stoves and ranges as well as any other heat 
producing apparatus shall be installed in compliance with the provisions of 
Part 21 of the Code. 

Section 15. All master, service, meter and controlling gas cocks, as well 
as the gas keys on lighting fixtures, shall be of brass and conform to the 
Boston type. 

The plugs of all cocks and keys must be ground to a smooth and true 
surface for their entire length; have not less than three-quarter inch bearing; 
have two flat sides on the end for the washer and have two nuts. Stop pins 
to cocks and fixture keys must be screwed into place. 

Cocks which are integral parts of gas appliances and are supplied through 
master cocks shall have screwed-in stop pins or an equivalent means to 
provide definite closing positions. 

Section 16. No swinging gas brackets will be permitted unless the 
burner is provided with a globe or guard. A stiff gas bracket may be used 
without a globe or guard if the length of the bracket is not less than five 
inches, measured from the burner to the wall. 

Brass tubing used for arms of fixtures shall be at least No. 18 standard 
gauge with full threads. Rope or square tubing shall be brazed or soldered 
into fittings. 

When brass or copper piping is used on the outside of plastering, in dentist 
chairs or work of a similar character, it shall be classed as fixtures. 

In theatres and buildings where illuminating gas is used for emergency 
exit lights there shall be at each exit a gas outlet equipped with a two-light 
bracket. The brackets shall be fitted with open flame burners having built-in 
lava tips. 

The drawings of said theatres and buildings shall be marked showing gas 
outlets. 

(293) 



Sees. 17=18 

Flexible Tubfrig 
S^tion 17. Appliances which are necessarily portable, or which have 
to be moved from place to place, may be connected with flexible tubing. 
Only practicable lengths of not over eight feet, approved quality tubing, and 
designed so as to permit of secure attachment to the nozzle of the appliance 
and the controlling cock on the house piping will be permitted. 

Cocks controlling tubing connected appliance shall be located on the rigid 
piping at the source of the gas supply to the tubing. 

Water Heaters 

Section 18. Gas water heaters shall not be installed in bathrooms, 
industrial wash rooms, toilets, shower baths, bedrooms, or in any room or 
place where its operation would cause a hazard to persons or property. Water 
heaters of the closed bottom type shall not be placed directly on combustible 
floors, but suitable insulation shall be provided. No gas water heaters shall 
be located closer than six inches to any combustible wall, even though the 
wall is protected. 

No water heating appliance shall be installed in a closed system of water 
piping unless proper water relief valves are provided and the storage boiler 
conforms to the requirements of the Code. 

No manually controlled water heater shall be placed in a cellar or base- 
ment unless approved by the building commissioner. 

No range boiler or other vessel or tank in which heated water is stored 
shall be connected with the street pressure unless it is equipped with tem- 
perature, pressure relief and vacuum relief valves or valve placed on boiler 
or tank side of shut-offs. Temperature, pressure relief and vacuum relief 
valves shall have their discharge openings piped to conform with the Code. 

No such valve shall be used unless approved by the building commissioner. 

The manually controlled circulating and storage types of gas water heater 
ntermittently operated, may be exempt from the requirements for a flue 
connection. 

All automatic storage types of water heater shall be connected to a chimney 
or suitable flue and shall be equipped with an effective device which will 
automatically turn off the gas to the main burner in the event that the flame 
is extinguished. 

Any storage type water heater equipped with automatic control which 
has a demand rating greater than 31,800 B. t. u. (60 cubic feet per hour) 
shall be supplied by an independent fuel line from the meter to the appliance. 

Automatic instantaneous water heaters shall be supplied by an independent 
fuel line from the meter to the appliance. The fuel line must never be smaller 
in diameter than the inlet of the heater. The appliances must be connected 
to a chimney or suitable flue. 

The cold water supply to an automatic instantaneous water heater shall 
be such as to provide sufficient pressure to properly operate the water valve 
when drawing water from any hot water faucet. 

(294) 



Sec. 19 

Chimney and Flue Connections 

Section 19. Every gas appliance having a demand in excess of 37,100 
B. t. u. (70 cubic feet per hour) and all automatically controlled appliances 
shall be connected to an effective flue. On account of its intermittent use, 
the domestic size gas range, the hand controlled water heater, and room 
space heater may be exempt from the requirement for a flue connection. 

Water heaters classed as observation heaters with no remote control and 
equipped with safety device to shut off gas to the main burner in the event the 
pilot flame is extinguished shall be exempt from this section. 

Automatic controlled appliances having a demand rating not greater than 
13,250 B. t. u. (25 cubic feet per hour) and equipped with an effective device 
which will automatically turn off the gas to the main burner in the event 
that the flame is extinguished shall be exempt from the requirements for a 
flue. 

When gas appliances are connected to a ventilating flue, the flue shall be 
constructed of brick walls not less than eight inches thick, or with walls four 
inches thick lined with suitable flue lining. Steel stacks shall be permissible 
under such conditions as the commissioner shall prescribe. 

All chimney flues shall have a well with a built-in clean-out door at least 
two feet below the entrance of the lowest flue piping. 

The horizontal flue piping from an appliance shall enter the side of a chimney 
through a metal thimble or masonry flue ring, and shall not be inserted beyond 
the inside wall of the chimney. If more than one entrance is made to the 
chimney, the thimble should be at different levels or at right angles to each 
other. 

The horizontal flue piping should be as straight and short as possible 
and the appliance should be located as near the chimney as practicable. 
No horizontal flue greater in length than twenty feet shall be allowed and 
for long runs a pitch or rise of at least one half inch to the foot shall be main- 
tained from the appliance to the chimney. 

Flue piping shall be at least twelve inches from any combustible material 
unless the material is provided with a protection as effective as a metal shield 
laid on a sheet of asbestos one-quarter inch thick; placed one inch from the 
combustible material, in which case the distance shall not be less than six 
inches. The width of the shield shall be at least twice the diameter of the 
flue pipe. 

No flue piping of any appliance shall be connected to the flue piping of any 
other appliance by the use of right-angle connections; such connections shall 
be made with a Y or 45-degree fitting. 

The flue piping or connections shall not be smaller than the size indicated 
by the vent collar of the appliance. Where the appliance has more than 
one vent the flue piping shall equal the combined area of the vents for which 
it acts as a common connection to the chimney. 

Every flue connected appliance (except an incinerator), unless its con- 
struction serves the same purpose, shall be equipped with an effective back 
draft diverter. If the draft hood is the cone type it must be installed in a 
vertical position adjacent to the appliance. 

(295) 



Sees. 20=21 

In the absence of suitable masonry chimneys, the vents from hotel kitchen 
equipments, industrial and other heavy duty appliances, exhausting into 
hoods, may have products of combustion from the hoods removed through 
an exterior wall to the outer air by a fan and metal duct. 

The discharge from the system shall be carried to a sufficient height to 
protect adjoining buildings from the products of combustion. 

Vent stacks erected on the outside of buildings may be fastened to the 
building walls by brackets or strap iron anchors and must conform to the 
requirements of the commissioner. 

Central House Heating Boilers and Furnaces 

Section 20. Gas boilers and furnaces shall be located so that all parts 
are accessible for adjustment, operation and repairs. The location of any 
house heating boiler or furnace must be ventilated to provide sufficient air 
for combustion and the location of the heater shall not constitute a fire 
hazard. 

Heaters should be located near the chimney so as to provide as short and 
direct a flue connection as possible. 

Down draft diverters come as standard equipment on all A. G. A. approved 
appliances and must be used on all installations. 

A master cock shall be provided ahead of all control devices on the appliance. 

All central house heating appliances shall be supplied by an independent 
fuel line from the meter to the appliances. 

The gas pressure regulator or governor requiring access to the atmosphere 
for successful operation shall be vented to the outer air by standard weight 
wrought iron or steel pipe not less than three-eighths inch or into the com- 
bustion chamber adjacent to a constantly burning pilot unless its construc- 
tion is such as to prevent an escape of gas from the vent opening in the event 
of diaphragm failure. 

Conversion of Central House Heating Appliances 

Section 21. No boiler or furnace designed for other fuels shall be con- 
verted to the use of gas fuel unless the following regulations are complied 
with : 

(1) Either a thermostatic pilot light, so constructed and adjusted that 
no gas can flow through the main burner unless the pilot light is burning, 
or some other similar type of safety device serving this same end shall be 
employed. The operation of the safety device shall not depend on the clos- 
ing of an electric circuit to shut off the main gas supply. 

(2) The boiler or furnace shall be equipped with safety devices arranged 
to limit high steam pressure or water temperatures or high air temperatures 
in warm-air furnaces which are equipped with air circulating fans. It is 
recommended that in steam or vacuum vapor boilers means be provided to 
guard against firing a dry boiler or one in which the water is dangerously 
low, and that in warm-air furnaces not equipped with air circulating fans 
means be provided to guard against excessive temperatures in the distrib- 
uting system. Safety devices operated electrically shall not depend upon 

(296) 



Sees. 22-24 

the closing of the circuit to shut off the main gas supply. This requirement 
should not be construed as prohibiting the use of electrical regulating devices, 
provided the required safety devices are also installed. 

An approved gas pressure regulator of sufficient size shall be installed in 
the gas line leading to the appliance. 

All boilers or furnaces shall be connected to chimneys. The size of the 
flue and flue piping shall be proportionate to the maximum rate of gas 
consumption not less than one square inch in cross-sectional area for each 
7,500 B. t. u. of gas per hour. 

No damper shall be installed in the flue pipe unless provided with means 
for permanently securing it in the proper position or unless so arranged that 
the main gas valve will not open until the damper has opened and the damper 
will not close until the main gas valve has closed, in which case the damper 
and draft hood shall be so located and so proportioned that failure of damper 
operation will not cause the formation of carbon monoxide. 

Incinerators 
Section 22. All incinerators shall be installed in accordance with pro- 
visions of the Code, Section 2116. 

Gas Engines 

Section 23. Gas engines must be connected to a service from which no 
gas for illuminating purposes or constant burning pilot lights is used. 

Diaphragms and bags must be inclosed in substantial gas tight metal 
housing, vented to the outer air. 

Exhaust pipes shall be run to the roof of building when possible and be 
kept at least eight inches from woodwork and any combustible material 
and when carried through floors or partitions must be covered with a fire- 
proof covering and provided with a ventilated thimble at least six inches 
larger in diameter than the pipe. 

Mufflers and exhaust pots must be made equal in strength to the cylinders 
of the engine, and be placed at least twelve inches from any combustible 
floor or material. 

Gas=Fired Power Boilers 

Section 24. Power boilers above three horse power capacity shall con- 
form to the Massachusetts Standard established by the Massachusetts 
Department of Public Safety. 

Power boilers of three horse power capacity or less shall conform either 
to the requirements of the American Society of Mechanical Engineers or to 
the Massachusetts Standard, and shall be satisfactory to the building 
commissioner. 

All such boilers shall bear the stamp of approval of the Massachusetts 
Department of Public Safety or of the American Society of Mechanical 
Engineers indicating conformity with respective requirements. 

No furnace or boiler for heating shall be placed upon a wooden floor unless 
the floor is made safe with fire-resistive materials satisfactory to the building 
commissioner. 

(297) 



Sees. 25=27 

General Requirements 

Gas boilers shall be located so that all parts are accessible for adjustment, 
operation and repairs. The location must be ventilated to provide sufficient 
air for combustion and the location of the boiler shall not constitute a hazard 
to persons or property. 

Gas boilers (other than the pressing machine and similar individual 
small units) when located above the cellar shall be supported on two parallel 
I-beams, placed out of the heat zone and laid across the floor timbers, 
adequate in length and weight to distribute the floor load. 

The floor shall be covered with a protection as effective as a sheet of asbestos 
one-half inch thick laid beneath a sheet of No. 26 gauge galvanized metal 
extending under the I-beams; with four-inch hollow tiles laid between the 
I-beams under appliance, the cells arranged to provide a continuous open 
air space, the tiles to be covered with a sheet of three-eighths inch boiler plate 
supported on the I-beams. 

Boilers for pressing machines and similar small units having closed or 
semi-closed bases shall not be placed directly on combustible floors, but 
suitable insulation shall be provided. 

Bakery Ovens 

Section 25. Application must be filed in and permit obtained from the 
building department for the location of ovens and the building must con- 
form to the Building Code. 

Change of Use or Occupancy 
Section 26. No additional gas appliances or meters shall be permitted 
in a place of habitation where there is a change of use or occupancy unless a 
permit for such change has been obtained and the building conforms to 
the requirements of the Building Code. 

Gas Company Exceptions 
Section 27. Nothing in these regulations shall be construed to affect the 
operations of any gas company upon its own premises or upon its mains or 
service pipes. 

James H. Mooney, 

Building Commissioner. 

G. Lynde Gately, M. D., 

Health Commissioner. 



(298) 



FIRST FIRE ZONE 

All that portion of the city which is included within a line beginning at the 
intersection of the centre lines of Dover and Albany streets, and thence 
running east through the centre of said Dover street to the harbor commis- 
sioners' line; thence by said harbor commissioners' line around the northerly 
portion of the city to a point on Charles river at the intersection of said line 
with the easterly line of St. Mary's street extended; thence along said east- 
erly line of St. Mary's street and the boundary line between Brookline and 
Boston to the centre of Longwood avenue; thence through the centre of said 
avenue to the centre of St. Alphonsus street; thence through the centre of 
said street to the centre of Ward street; thence through the centre of said 
Ward street to the centre of Parker street; thence through the centre of said 
Parker street to the centre of Ruggles street; thence through the centre of 
said Ruggles street to the centre of Washington street; thence through the 
centre of said Washington street to a point opposite the centre of Palmer 
street; thence through the centre of said Palmer street and through the 
centre of Eustis street to the centre of Hampden street; and thence through 
the centre of said Hampden street and the centre of Albany street to the 
point of beginning. 



SECOND FIRE ZONE 

All that portion of the city which is included within a line beginning at the 
intersection of the boundary lines between the City of Boston and the cities 
of Somerville and Everett; thence by the boundary lines between the City of 
Boston and the cities of Everett and Chelsea to the intersection with the 
centre line of Trumbull street extended northerly; thence by said centre line 
of Trumbull street extended, the centre line of Trumbull street and said 
centre line extended southerly to the harbor line; thence by said harbor 
line to its intersection with the easterly line of Pier No. 5, belonging to the 
Boston and Albany Railroad Company; thence by a straight lirle across 
Boston Harbor to its intersection with the harbor line at the easterly corner 
of Pier No. 1 in South Boston; thence by the harbor line in the northerly, 
easterly and southerly portions of South Boston to an angle in said harbor 
line nearly opposite the intersection of the centre line of Columbia road with 
the centre line of location of the Old Colony Railroad; thence by a straight 
line to the said intersection; and by the centre lines of Columbia road, Blue 
Hill avenue, Seaver street, Columbus avenue, Atherton and Mozart streets, 
Chestnut avenue, Sheridan, Centre and Perkins streets, South Huntington 
avenue, Castleton street and the centre line of said Castleton street extended 
to the boundary line between the City of Boston and the town of Brookline; 
thence by said boundary line to a point therein one hundred feet southwest 
of Washington street in the Brighton district; thence by a line parallel to 

(299) 



and one hundred feet southwesterly from the centre line of Washington 
street to an angle formed by the intersection of said line with the extension 
of a line parallel to and one hundred feet northwesterly of the centre line of 
Market street; thence by said extension and said line parallel to and one 
hundred feet northwesterly of the centre line of Market street to a point 
one hundred feet south of the centre line of Western avenue; thence by a 
line parallel to and one hundred feet south of the centre line of Western 
avenue and said line extended to a point in the boundary line between the 
City of Boston and the town of Watertown south of Watertown Bridge, 
so called; thence by said boundary line and the boundary lines between the 
cities of Cambridge and Somerville to the point of beginning, but not includ- 
ing area within the boundaries of the first fire zone. 

Also those portions of Hyde Park upon or within one hundred feet of the 
following named streets and squares: Everett square, so called; Fairmount 
avenue from River street to the Neponset river; River street from the loca- 
tion of the Boston and Providence Railroad to Winthrop street; Hyde Park 
avenue on the easterly side from the northerly side of Oak street to Everett 
street; Hyde Park avenue on the westerly side from the northerly side of 
Pine street extension, so called, to a point on said Hyde Park avenue oppo- 
site the southerly line of Everett street; Harvard avenue from River street 
to Winthrop street; Maple street from River street to a point one hundred 
and eighty feet southerly therefrom; Central avenue from River street to 
Winthrop street; Davison street from Fairmount avenue to a point three 
hundred feet northeasterly therefrom; Grove street; Pierce street from 
Fairmount avenue to a point three hundred feet northeasterly therefrom; 
Knott street from Fairmount avenue to a point three hundred feet easterly 
therefrom; Railroad avenue from Fairmount avenue to a point three hun- 
dred feet northeasterly therefrom; Station street from the Neponset river 
to a point three hundred feet northeasterly from Fairmount avenue; Walnut 
street from Fairmount avenue to a point three hundred feet southwesterly 
therefrom; Maple street from Fairmount avenue to a point one hundred 
and twenty-five feet westerly therefrom. 

[Orel 1913, ch. 4 and Rev. Orel. 1947, ch. 41, sec. 1\ 



(300) 



INDEX TO BUILDING CODE 

Section 
Group A— THEATRES 301 

Group B — HALLS (Churches, gymnasiums, dance halls with main floor over 900 square 

feet) 401 

Group C — SCHOOLS (Buildings partly or wholly so used) 501 

Group D— HOSPITALS, JAILS, ASYLUMS, HOMES FOR AGED, ORPHAN- 
AGES, SANITARIUMS, NURSERIES 601 

Group E— COMMERCIAL BUILDINGS OF HAZARDOUS OCCUPANCY (Plan- 
ing mills, woodworking plants, box or mattress manufacturing, dry 
cleaning) 701 

Group F— OFFICES AND COMMERCIAL BUILDINGS, RESTAURANTS, 
WHARF BUILDINGS, POLICE AND FIRE STATIONS, MU- 
SEUMS, LIBRARIES. Also buildings for storage and sale of goods, 
wholesale and retail stores and factories and workshops (materials 
handled not highly flammable), and printing plants and buildings for 
storage of transient freight; garages for more than six cars and hangars, 801 

Group G— COMMERCIAL BUILDINGS OF NON-HAZARDOUS OCCUPANCY 

(Ice, power and pumping plants, cold storage plants, creameries, brew- 
eries; also factories and workshops using incombustible and non- 
explosive materials) 901 

Group H— HOTELS, DORMITORIES, LODGING HOUSES, CONVENTS, 
MONASTERIES AND CLUB HOUSES (With sleeping accommoda- 
tions for ten or more persons or for more than three families). Also 
apartment houses accommodating more than three families 1001 

Group I — DWELLINGS (For not over three families), and dormitories, lodging houses, 
clubs, convents and monasteries (with sleeping accommodations for less 
than ten persons) 1 101 

Group J— MISCELLANEOUS STRUCTURES,. Tanks, towers, signs, amusement 
park structures, grandstands, reviewing stands and garages for six cars 
or less 1201 



Section 

ACCESS PANEL for fire extinguishing apparatus 3010 

ACOUSTICAL CEILING CONSTRUCTION in Buildings of Type I 1602-f 

ADMINISTRATION 

Abandon application after six months 110-g 

Actions pending on effective date of Code 103 

Acts repealed 102 

Amendments of Code by City Council 105A 

Annual Report 115 

Appeals (see Board of Appeal) 118, 119 

Application of other statutes to Building Department 104 

Applications for permit 110 

Appointment of employees 109-d,e 

Building Commissioner — qualifications 109-b 

Building height allowed 136 

Boards (see Boards of) 

Civil Service rights of employees , 109-c 

Courts and jurisdiction 123 

Deputy Commissioner may be appointed 109-e 

Dynamos — Applications for 110-a 

Elevators and escalators — Installation of 135 

Employees not to engage in other work 109-f 

Employees — Reappointment 109 

Examination of plans 1 10-h 

Extension of application may be granted 110-g 

Extension of permit may be granted ....... H 1-e 

Fees , ...... 112 

Inspection 113 

Inspectors — Appointments and qualifications 109»-d 

Maintenance of furnaces and boilers HO-a 

Organization of department 109i 

Permits -.••••. ; Ill 

Hans — Submit, with specific information . .. 1 10-e,f 

Powers and duties of Building Commissioner 116 

Records 109-g 

Refusal of permits 11 1-b 

Scope of Code J07 

(301) 



Section 
AFFIDAVITS FROM ARCHITECTS AND ENGINEERS 110-i, 111-h 

AGGREGATE (see Concrete) 

AISLES (see Group — Occupancies under Exits or Assembly rooms) 

AISLES AND SEATING in class rooms 506 

ALLOWABLE BEARING VALUE ON SOIL FOR FOUNDATION 2904-b 

ALLOWABLE LOAD ON PILES 2909 

ALLOWABLE STRESSES (see under Stresses) 

ALTERATON of pre-Code buildings 107-c, d, e, f, g, and 1414 

AMUSEMENT PARK STRUCTURES 1201 to 1207 

ANCHORAGE OF 

Columns, steel and iron 2819 

Masonry veneer 1415-b 

Masonry walls 1408-b,c 

Reinforced concrete walls 1405-k 

Reinforcements 2644, 2645 

Steel joists 2818-h,i 

Web reinforcements 2646 

Wood floors— Type III. . 1604-h 

Wood joists, beams and girders 1605-d, 2506-i 

APARTMENTS, Houses (Group H-Part 10) 

Assembly halls 1001-c 

Boiler rooms to have two-hour separation 1009-d 

Construction of ceiling and first floor 1001-d 

Corridor and stairway to be lighted 1005-f 

Corridor walls 1005-d 

Corridor width 1005-d 

Doors to roof not to be locked . 1005-e 

Exit from an apartment to be not more than 50 feet from nearest exit 1005-c 

First floor more than 2,000 square feet and more than three stories high shall 
be of Type I or Type II. Basement ceiling of all other more than 2,000 

square feet and three stories to be of one-hour fire resistance 1001-d 

Kitchens, light and ventilation 1006 

Partition separating apartments 1001-e 

Sleeping rooms 1007 

Sprinklers 1008 

To have one room 120 square feet 1007-a 

Toilets : m 1006, 1007-d, 1009-a,c 

Type V construction not to be used . 1001-b 

Type VI not to be used for more than four families or more than two families 

above first story 1001-f 

Windows 1006 

APPEAL (see Board of Appeal) 

APPLICATION for Permits 110-a 

May be extended ninety days 110-g 

Number of persons to be served by an exit to be stated on 1803 

ARBITRARY moment coefficients 2636 

ARCHES, MASONRY 2414 

AREA (see Group — Occupancies and 305-b and 106) 

Within a stairway in Group C 501-c 

Within a stairway not to be used for storage 1507 

ASSEMBLY HALLS, Lights and Ventilation 408 

In Group B under Exits and Entrances 405 

(see Group Occupancies also) 1001-c, 1008-a, 1803 

ASSUMED STRENGTH OF CONCRETE MIXTURES 2611 

ATTICS, Exits 1804-b 

AUDITORIUM, DANCE HALLS, ETC., One person per 6 square feet 1803 

AUTOMATIC SPRINKLERS IN PRE=CODE BUILDINGS, in Groups E and F, 3001-b 
(see also under Sprinklers) 

AWNINGS, roof drains 1703-a 

BAKERY OVENS (see also Sec. 25, Gas Regulations) 2119 

BACKFLOW OF SEWAGE 3103-f 

BALCONIES, CONNECTING 1815-f,g 

BALCONY RAILING 2309 

BASEMENT, CEILING To be at least one-hour fire resistant 1001-d 

LIVING AND SLEEPING ROOMS 1007-c 

Not to have wooden columns or partitions 1507-b, 1604-d 

TO BE WATERPROOFED (if surrounded by water-bearing soil), 2902-e 

BATHROOM, windows not less than one eighth floor area and not less than 

6 square feet 1006-a 

BEAMS, Built-up, wooden 2506-g 

Deflection 2808-f 

(302) 



BEAMS — Continued Section 

Encased in concrete 2650 

Notches in wooden ; 2506 

Reinforced concrete beams that serve as walls to meet requirements of 

non-bearing walls 1405-f 

Spandrel 2651 

Steel beams and girders . 2808 

Structural steel beams framed into wall to have protection against fire. . 1405-j 
Support on hollow masonry 1410-a 

BEARING, On concrete footings 2682 

Partitions of masonry for one-story to have thickness of one-twentieth 

the height or length, etc 1406-e 

PARTY WALLS of masonry not less than 12 inches thick 1406-f 

WALLS, exterior 1406-d 

Panel 1406-g 

BLOW-OFF TANK 3103-e 

BOARD OF APPEAL 117 

Appeals to 118 

Decisions of 119 

BOARD OF EXAMINERS 120 

OF QASFITTERS 121 

BOILER OR FURNACE, Maintenance of 110 

Permit for installation required 2119 

Waterproofing to be protected against damage 2902-e 

IN ASSEMBLY HALL NEAR STAGE, to have two-hour separation, 410 

BOILER ROOMS 

In buildings more than three stories, to have two-hour separation 1009-d 

In Group D buildings, to have three-hour separation 608 

In Group H buildings, to have two-hour separation 1009-d 

In schools, to have two-hour separation 510 

In Type IV and Type VI buildings, more than one family 1101-c 

BOILERS 2105-b, 2108-a, 2109 

Water pressure in 3114 

BOND IN MASONRY 2412 

BONDING OF FRESH AND HARDENED CONCRETE 2623 

BORINGS AND TEST PITS 2903 

BOUNDARIES OF FIRE ZONES 202 

BOUNDARY LINE OF A LOT 1006-f 

BRACES IN WOODEN WALLS 1417-c 

BRASS PIPE 3118 

BREWERIES 901 

BRICK 2202, 2403 

UNIT COMPRESSIVE STRESS 2413-a 

BRIDGING, Steel 2818-g 

Walls and partitions 2508-a-c 

Wood 2506-e 

BUILDING COMMISSIONER 109-a,b 

HEIGHT ALLOWED 136 

INSPECTION 113 

LICENSE 120 

BY TYPE OF CONSTRUCTION 124 

CLASSIFICATION AS TO TYPE 125 

FIRE RESISTANCE 124 

BUILDINGS ON WHARVES USED FOR STORAGE 801-d 

GROUP C, in first or second fire zone shall be of Type I or Type II 

construction 203-h 

To have a supply of pure water 3101-a 

To have toilet accommodations 3101-b 

IN first or second fire zones erected as garages for more than four 

cars to be of Type I or Type II 203-g 

MORE THAN 125 FEET HIGH, soil stack at least 5 inches... 3104-g 
MORE THAN THREE STORIES HIGH, first floor commercial, 

and more than two families above second floor; sprinklers 3101-b 

OF TYPES III, IV, VI, wooden roof not to extend beyond wall, 1701-e 

OF TYPE VI — Not to be used for more than four families 1001-f 

For dwellings in secoud fire zone 203-d 

V — In second fire zone 203-e 

BUILDING DRAINS, for waterclosets and urinals 3104-b 

(303) 



Section 

BUILT-UP GIRDERS, wooden 2506 

BULKHEADS, for display windows 1902-j 

CAISSON PIERS 2907-b,c 

CAISSONS 2907 

CAST IN PLACE PILES (Concrete) 2909-g, 2912 

IRON 2805 

COLUMN CAPS 1604-e 

PIPE 3116 

STEEL 2804 

STONE 2405 

CEILINGS of buildings more than 2,000 square feet and three stories high, one- 
hour fire resistance 1001-c, 1101-c 

Acoustical in Type II, of wood or other combustible material 1602-f 

Finished in wood — Type I and Type II 1602, 1603 

BASEMENT, in buildings more than three stories high, one-hour fire 

resistance 1101-j. 2210 

In Group D, Division 2, buildings 601-c 

CEILING UNDER ROOF (see also under Floor Construction) 1701-b 

CELLAR 1603-f, 1608, 1902 

CEMENT MORTAR SHALL BE COMPOSED OF 2411-h 

PLASTER SHALL BE COMPOSED OF 2202 

CHANGE OF OCCUPANCY 107, 133 

CHASES, RECESSES, CORBELS AND LINTELS 1405-i, 1411 

CHIMNEY FLUE LINING 2102 

FOUNDATION 1411-g, 2101 

IN APARTMENT OR HOTEL ... 1009-c 

NOT TO BE BUILT NEAR WOODEN MEMBERS. .2103, 2104, 2105 
CHIMNEYS (see Part 21) 

CHURCHES— Group B 401 

CHUTES AND DUMB-WAITERS 1503-h 

CLASSIFICATION OF BUILDINGS BY TYPE OF CONSTRUCTION 124 

AND ALLOWABLE LOADS ON FOUNDATION BEAR- 
ING MATERIALS 2904 

CLAY TILE 2102, 2407 

For chimney construction 2407 

CLEARANCES 

Ends of wooden beams resting upon masonry to have four-inch clearance .... 2506-1 

Furnace 2109 

Over hot plates 2112 

Pipes and chimneys 2104, 2111 

Range hoods 2114 

Smoke stacks 2105 

Steel joists 2818-j 

CLEAN-OUTS IN DRAINS 3103-g 

CLOSETS on or under stairways 1507, 1808-n 

COLUMN BASES OF STEEL AND IRON 2819 

COLUMNS 

Cast iron 2810, 2816 

Combination 2677 

Concrete 2669 to 2674, 2677 

Concrete filled pipe columns 281 1 

Steel 2807 

Type 1 1602-b 

Wood 2505 

Wooden, not to be used in basement 1604-d, 1607-b 

COMBINATION AND RIBBED SLABS 2653 

COMPOSITE BEAMS 2808-h 

PILES 2914 

CONCEALED OPENINGS THROUGH FLOORS 2508-d 

CONCENTRATED LOADS 2306, 2652 

CONCENTRATION OF HEAVY LOAD 2820-e 

CONCRETE (see Part 26) 

Aggregate 2606 

Anchorage 2644, 2645, 2646 

Assumed strength of mixtures 2611 

Average oovi 

Axial and bending stresses 2676 

Beams, compressive reinforcement ..,.,.. 2649 

(304) 



CONCRETE— Continued Section 

Bearing on footings 2682 

Ronding to fresh or hardened concrete 2623 

Cement 2605 

Columns 2669, 2674 

Combined footings 2680-d 

Construction joints 2622, 2668 

Controlled 2610, 2612 

Cover for reinforcement 2627 

Reinforcement in, for pile caps 2907-f 

Curing 2621 

Depositing in cold weather 2620 

Exposed to weather 2611, 2612 

Forms and equipment 2615 

Inspection of 2603 

Moment coefficient 2636 

Openings in fiat slabs 2667 

Placing 2619 

Point of inflection in fiat slabs 2660 

Proportions and consistencies 2614 

Reinforcement 2608 

Ribbed slabs 2653 

Shrinkage reinforcement 2651 

Slenderness ratio 2807-b 

of reinforced concrete beam 2647 

Spandrel beams 2651-b 

Stress 2629, 2930 

Structural concrete 2610 

T beams 2648 

Table of stresses 2629, 2630 

Temperature reinforcement 2651 

Test of materials 2604, 2612, 2613 

Transporting 2618 

Two-way slabs 2654 

CONCRETE BLOCKS 2202, 2406 

CLASS I AND CLASS II 2202 

DEPOSITED IN COLD WEATHER 2620 

FILL 2202 

FILLED PIPE COLUMNS 2811 

STEEL PILES 2913 

FOOTINGS 2642, also 2679 to 2682 

INSPECTION 2603 

REINFORCEMENT 

Bending 2624 

Compression in beams and girders 2649 

Placing 2625 

Protective cover 2627 

Shrinkage and temperature 2651 

Splices in 2626 

Web reinforcement 2639, 2640 

WALLS 1405, 2678 

CONDUIT EMBEDDED IN CONCRETE 2202-g, 2628 

CONNECTING BALCONIES 1815-f 

CONSTRUCTION JOINTS IN CONCRETE 2622 

FLAT SLABS 2668 

TYPES OF 125 

WITHIN FIRE ZONES 203 

COPINGS 1703-a 

COPPER, Pipe 3118 

CORNICES, Metal 1402-d 

Rain water discharging on a public way 1703-a 

Wood (not in fire zones) 1402-d 

CORRIDORS, General (see Group — Occupancy) 

And passageways 1805 

And stairways in Group H to be lighted 1005-f 

Group C 505 

Group H 1005-d 

Not to have any obstruction 1005-c 

Space to lobby 1814 

Walls in Group H to be one-hour fire resisting 1005-d 

Width of, in Group H 1005-d 

COURT WALLS 1402-c 

DANCE HALLS, Steel deck floor not to be used 2830-e 

(305) 



Section 
DEFINITIONS 

Concrete 2601 

General 106 

Masonry 2402 

Pertaining to plumbing 3102 

Walls and partitions 1401 

DEFLECTION OF STEEL BEAMS, 1/360 of span 2808-f 

DEPTH OF FOUNDATION 2902 

DESIGN, Of wood 2501 

DETACHED GARAGES, Foundation of 2902-d 

DIAGONAL FLOOR FRAMING 2507-b 

DINING ROOMS, Light and ventilation 1006-c,e 

DISPLAY WINDOWS 1902-j 

DISTANCE FROM LOT LINES (see Group— Occupancies under Exterior Walls) 
DOORS, FROM STAIRWAY TO ROOF NOT TO BE LOCKED 1005-e 

FIRE, CONSTRUCTION 2214 

fire-resistive requirements 2213 

on each side of party wall openings 1901-C-4 

General requirements 1302, 1901, 2213, 2214 

To swing in direction of egress 1806-d,e, 1817-c 

AUTOMATIC SELF=CLOSING 1901 

DOORWAYS IN ENCLOSURES 1503-f 

AS EXITS 1806 

NEAR FIRE ESCAPES 1812 

DOWELS, from Pedestal to Column 2682 

DRAINAGE, Filling, on roof of Type I and Type II 1701-c, 1703, 2620 

Mechanically discharged 3107 

SYSTEM AND MATERIALS 3112 

System design and method of construction 3103 

DRAINS 3103 

DRAINS FOR RAIN WATER 3105 

DRINKING FOUNTAIN 3115 

DUCTS, Ventilating 1506 

DUMB=WAITER AND CHUTES 1503-f 

DUTIES OF THE COMMISSIONER 116 

DYNAMOS, Application for 110-a 

EFFECTIVE DEPTH of reinforced concrete beams and slabs 2634 

EGRESS, Pre-code buildings to have at least two in number (see also Exits, Part 18) 107-e 

ELECTRIC PLATES 106, 2112 

ELEVATORS, ESCALATORS AND ELEVATOR SHAFTS 135 

As exits , 1814 

Fire protection on support for elevator guides and elevator machines 1602-b 

Group A buildings 304-b 

Group B buildings 404 

Group C to Group G, same as in 504-a 

Passenger enclosure doorways 1503-f 

Shafts to be ventilated at top 1503-i 

Shaft windows 1902 

ENCLOSURE OF CHUTES AND DUMB=WAITERS 1503-h 

VERTICAL OPENINGS (see also Group— Occupancy) 1504 

TO BE USED FOR PURPOSE FOR WHICH IT WAS CON- 
STRUCTED 1507 

ENGINES, Applications for 110-a 

ERECTION OF STEEL 2817 

EXCAVATION, Removal of water 2617, 2901 

EXEMPT FROM CODE 107-a 

EXISTING MASONRY WALLS 1414 

EXITS (see Group — Occupancies) 

And entrances, Group B — Part 4 . 405 

Corridors not to have any obstructions 1805 

Description and kind of exits 1802 

Distance to an exit from an occupancy 1804-h,i 

Enclosures _ • • ■ J817 

Exit doors shall swing in direction of egress 305-k, 1806-e 

From a flat roof occupied by persons 1804-b 

From an apartment — must not be over 50 feet from nearest exit 1005-c 

From H and I occupancies 1005-b,g, 1105 

From or to an attic 1804-b 

(306) 



EXITS— Continued Section 

General requirements, Part 18 1801 

Group C— Part 5, Schools , 505 

In Group E no point in story to be over 100 feet from nearest exit 705-b 

Lighting and maintenance 1819 

Must be in a continuous path 1802-e 

Number and location of 1803, 1804 

Number of persons served by, based on square feet per person 1803 

Number of persons to be served by, to be stated in application for permit.. . . 1803-a 

One from every story must be an interior stairway 1802-f 

Passageways to and from required exits not to be obstructed 1808-ni 

Room or group of rooms more than 2,500 square feet, or containing more than 

75 persons, to have two remote exits 1804-c 

Signs 307, 1802-e, 1818 

To be lighted 307, 1005-f 

To be satisfactory to the Commissioner 116-d 

Two remote from each story 1804-e 

EXPANSION AND CONTRACTION OF STEEL 2814 

JOINTS 2651-c 

EXTENSION OF APPLICATION 110-g 

WOODEN RAFTERS BEYOND MASONRY WALLS 1701-e 

EXTERIOR BEARING WALLS, Thickness of 1406-e 

Of masonry 1/16 height or length between 
lateral supports in top story, or 1/20 in 
all other stories, and not less than 8 inches 

in Type V or Type VI 1406-e 

AND BEARING WALLS OF REINFORCED CONCRETE shall 

be anchored to floors, etc 1405-k 

BEARING WALLS OF REINFORCED CONCRETE to have 1/25 

height or length 1405-d 

NON BEARING WALLS 1406-g 

STAIRWAYS AND RAMPS 1811 

STAIRWAY FROM A LOT LINE 1811-a.c 

to be enclosed if less than 15 feet from a lot line 1811-c 

OUTSIDE PASSAGEWAY to be as wide as an interior passageway, 1805-h 

WOOD FRAME WALLS 1417 

WALL (see also Group — Occupancies) 1402-d 

OPENINGS 1402-d 

WALLS, TYPE III, MAY BE 2-HOUR FIRE RESISTANT, 2201-e 

IV, MAY BE 2-HOUR FIRE RESISTANT, 2201-d 

BEARING WALL, WOOD TRIMMINGS 1402-d 

FACTORIES AND WORK SHOPS, One person per 35 square feet 1803 

FEES 112-a 

FENCE 107 

FINISH, Outside , 1402-j 

FIRE DAMAGE, restoration of 107-d 

DOORS 2213, 2214 

in fire walls 1302-g 

stop walls 1417-e 

ESCAPES, As exits 1812 

EXTINGUISHING APPARATUS (Part 30) 

Access panel 3010 

Water supply 3007 

LIMITS 201 

boundaries of 202 

PLACE 2107 

PROTECTION, For— 

Cast-iron columns 2204 

Reinforced concrete beams 2207 

Reinforced concrete columns 2205 

Reinforced floors and roofs 2208 

Steel beams, girders and trusses 2206 

Steel columns 2203 

PROTECTIVE, Covering injured by moving vehicles 2202-h 

RESISTIVE 

Bearing walls and partitions 2211 

Brick of Grade B 2403-g 

Ceiling construction 2210 

Doors 2213 

Fire door construction 2214 

Materials, construction and minimum qualities 2202 

(307) 



Section 
FIRE RESISTIVE— Continued 

Non-bearing walls and partitions 2212 

Requirements, Commissioner may not alter 116-1 

Roof and floor construction 2209 

Roof covering 2217 

Shutters 2215 

Windows 2216 

STOPPING 1604-a, 1607-a, 2202-i. 250S-d 

and nogging masonry may be supported on wood 1406-b 

STOP WALLS 403-g, 1402-a, 141 1-e, 2202-i, 2508-d 

TOWERS 1810 

WALL, Definition (see also 134. 1301, 1302-g) 1401 

Openings, fire door on each side of 1302-g 

FIRE WINDOWS 2216 

As substitute for firedoor, doors 1302-i 

ZONES 201 

Boundaries 202 

FIRST FLOOR, More than 2,000 square feet in Type I or Type II 1001-d 

FLAG POLES, Not part of building 136-c, 2003-c 

FLAT SLABS 2641, 2655, 2657 to 2668 

FLOOR CONSTRUCTION, Within enclosures 1504 

CONSTRUCTION: 

To be three-hour fire resistive 1602-a 

To conform to code as to design 1601 

TYPE I— FIREPROOF 1602-a 

Ceiling may be finished in wood 1602-f 

May be covered with wood 1602-c 

Mezzanine floor may be of wood 1602-d 

No hollow space under flooring 1 602-c 

TYPE II— SEMI-FIREPROOF 1603 

Ceilings may be finished in wood 1603-f 

May be wood covered 127, 1603-c, 2209 

Steel joists with ceiling 1603-e 

TYPE III — Thickness of steel stirrups and column caps 1604-e 

Wood not to be used for columns in basement 1604-d 

TYPE IV 1605 

TYPES I and II — May be covered with wood — no hollow space 

under flooring 1602-c, 1603 

TYPE I— Mezzanine may be of wood 1602-d 

TYPES I and II— CEILINGS, May bo wood finished. .. .1602-f, 1603-e 
Floor of steel joists with ceiling 1603-e 

TYPE IV — No structure of combustible material to support seats 

or aisles to be superimposed on floor construction 401-b 

GROUP H — First floor more than 2,000 square feet and more than 
three stories shall be of Type I or Type II. Basement ceilings of 
all others less than 2,000 square feet and three stories to be one- 
hour fire resistive 1001-d 

WOOD NOT TO BE USED for columns or partitions in basement. . 1604-d 

FRAMING, Diagonal 2507-b 

LOADS, Posting 114 

Steel Joists— Type II 127, 1603, 2209 

Unprotected against fire 1605, 1607 

Wooden 1405-b, 2507 

Not to be used for finish in garages 1208 

FOOTINGS 2642, 2679, 2907-a 

At different levels 2902-b 

Wooden 2907 

FOUNDATIONS (General— Part 29) 

Allowable loads on piles 2909 

Borings and test pits 2903 

Cast in place concrete piles 2912 

Classification and allowable load of foundation bearing materials 2904 

Composite piles 2914 

Concrete filled cylindrical piles 2913 

Depth of — 4 feet minimum 2902 

Excavation 2617, 2901 

Footings, caissons and pier caps 2907 

Foundation design 2906 

loads 2905 

load tests 2915 

to be supported on natural deposits 2902-a 

(308) 



Section 
FOU N DAT I ON S— Continued 

Load test3 on bearing material 2916 

Of detached garages 2902-d 

Piles, general requirements 290S 

loading tests 2917 

precast concrete 291 1 

wooden 2910 

Special permit 111-d 

Walls 1405-e, 1412 

Walls, reinforced concrete, not less than 8 inches 1405-e, 1412 

Wood, not to be used 2501-d 

FURNACES 2110, 2111 

AND BOILERS, Maintenance 110-a 

FUTURE FLOOR, Present roof in Type I and Type II, the filling for drainage may 

be of wood 1701-c 

GARAGE SEPARATION 801-f to 805, 1102, 1201, 1202-a, 1301-d 

GARAGES, To be Type I— Section 203-g 801-f, 805 

Cast iron columns not to be used in 2810-f 

Finish floor in, wood not to be used for 1208 

Foundation for detached 2902-d 

Over six cars — Type VI not to be used 801-b 

Six cars or less 1201-b 

Steel deck construction not to be used for floors _. 2820-e 

To have sprinklers if more than 10,000 square feet in area or if five 

stories or more in height 807-f 

GASFITTER'S LICENSE 121 

GIRDERS, Wooden built-up 2506 

GREENHOUSES 1903-a,b 

GRILLAGE, Structural steel 2907 

GROUP C BUILDINGS in first or second Fire Zone to be of Type I or Type II 

construction 203-h 

GYMNASIUM, Steel deck floor not to be used ' 2820-c 

GYPSUM, General— (Part 27) 2202 

Plain 2202-b 

Concrete 2410 

Concrete design and stress 2701 

Not to be used for a wearing surface 270 1-g, 2706 

Not to be used in floors of garages, dance halls 270 1-g, 2706 

Tile 2408 

HALLS , 401 

HANGARS— Section 801-Division 5 

HANGERS, For wooden joists 2506-d 

And support for drainage system 3119 

HEATING, Apparatus given (Part 21) 

Apparatus support 2117, 2119 

And PLUMBING — Group H 1009 

HEIGHT (see Group — Occupancies) 

HORIZONTAL EXITS 1815 

HOT PLATES 2112-a,b 

WATER SUPPLY 3114 

Heater, tankless 3114-o 

Tank, cistern pressure 3114-p 

Tank pressure 3114 

IMPACT , 2308, 2504-c 

INCINERATORS 2116 

INCREASE in area or in number of stories 107-f 

INSPECTION 113 

AND TEST OF FIRE EXTINGUISHING APPARATUS, 

HOSE, ETC 3009 

PLUMBING 3120 

OF GAS FIXTURES 116-i 

INSULATION, Filling FOR ROOF 1701-c 

INTAKE, FRESH AIR, IN COURTS 1006-b 

INTERIOR BEARING WALLS AND PARTITIONS, THICKNESS OF 1406-e 

RAMPS 1809 

STAIRWAYS 1808-n 

Closet under stairway 1 808- i 

(309) 



Section 
INTERIOR STAIRWAYS— Continued 

If enclosed corridor is omitted then basement and first floor to have automatic 

sprinklers 1805-d 

No obstruction on stairway or landing 1808-m 

Spiral stairs not to be used lS08-m 

To be enclosed above the second story 1817-b 

To extend to roof 1808 

Tread, rise and landings 1808-f ,g,h 

Width of stairway not to be less than 30 inches 1808-d 

INTERPRETATION OF CODE BY COMMISSIONER 111-g 

IRON PIPE PLUMBING 311b, 3117 

JOISTS, WOODEN NAILING STRIPS 2506-k 

JUNIOR BEAMS 2818 

KITCHEN FLOOR AREA MORE THAN 70 SQUARE FEET 1006-a,c 

not to be less than six feet wide and 48 square feet minimum 1007-a 

VENTILATION 1006-a,c,d 

WINDOWS, one-third of floor area and not less than 11 square feet. . 1006 

LADDERS AS EXITS 1813 

LATERAL FORCES 2309 

BRACING OF BEAMS 2803-d, 2808-b 

BRACING OF STEEL FLOOR FRAMING 1602-b 

not to be of wood 1603-b 

SUPPORT OF WALLS 1403, 1408 

LEAD PIPE IN PLUMBING 3118 

LIBRARIES 801 

LIGHT, exit 307, 1819-c 

and ventilation 806, 1006-a, 1106 

in assembly halls 408 

LIME PLASTER 2202 

LIMITED HABITATION (Group I) 1101-1107 

LINTELS NEED NOT BE FIREPROOFED, if span is not over 6 feet in bearing 

walls or 10 feet in non-bearing walls 1602-b 

LIVING ROOM 1006-a, 1106 

FLOOR, and floor on ground 1007-e 

LOADS, LIVE AND DEAD (Part 23) 2301 to 2312 

Due to partitions ^ 2304 

LOAD TESTS OF STRUCTURES 2313 

LODGING HOUSES, READING ROOMS, One person per 25 square feet 1803-a 

LOT LINE BOUNDARY, For light and ventilation 1006-f 

STAIRS, Not nearer than five feet from 1811-a 

LOUVRES 1505-a,l 

LUMBER, To be grade marked 2504-f 

SECOND-HAND 2504-f 

MAINTENANCE OF BUILDINGS 108 

FURNACES AND BOILERS 110-a 

MASONRY ARCHES 2414 

CHASES, RECESSES, CORBELS AND LINTELS 1411 

DEFINITION OF 2202, 2402 

PIERS 1409 

REINFORCED 2415 

SECOND-HAND MATERIALS 2416 

STRUCTURAL, not to be supported on wooden floor 1405-b, 1607-e 

UNIT STRESS 2413 

VENEER 1405-h, 1415-b 

WALL ANCHORAGES 1406-d, 1408-b 

WALLS 1406 to 1412 

Existing 1414 

Non bearing 1406-g 

OR PIERS not to be supported on wood 1406-b 

MATERIALS AND METHODS NOT COVERED BY CODE 116-1 

OF DRAINAGE SYSTEMS 3112 

MECHANICAL VENTILATION 1006-d 

MECHANICALLY DISCHARGED DRAINAGE 3107 

MEZZANINE FLOOR 1004-c, 1602-d 

(310) 



Section 

MINIMUM THICKNESS OF STEEL 2818 

MOMENT COEFFICIENTS 2636 

MORTAR, CEMENT 2411 

MOVING, TYPE VI BUILDINGS 107-h, 203-d 

PICTURE HOUSES 301, 401 

MULTIPLE OCCUPANCIES 124-b, 134, 1301 

TYPE URINALS 3115-c 

WATER CLOSET 3115-c 

NAILING STRIPS for wooden joists on girders 2506-k 

NON-BEARING PARTY WALLS OF MASONRY to be not less than eight 

inches thick 1406-f 

PARTITIONS OF MASONRY to have thickness 1/45 the 
height or length between lateral supports and at least 
3 inches 1406-f 

PARTITIONS OF REINFORCED CONCRETE to have 
thickness 1/60 the height or length between lateral sup- 
ports and at least 3 inches 1405-f 

WOOD PARTITIONS may be used in Types I, II, III and V 

under certain conditions 1417 

In Group F and Group G to subdivide space occupied by 
one tenant 1417-b 

In Group H and Group I to subdivide apartment occupied 
by one tenant 1417-b 

OBSTRUCTIONS IN AISLES PROHIBITED 306-c, 406-c 

OCCUPANCIES, Number of persons for certain area 1803 

BY GROUPS 132-a 

CHANGE OF 133 

MULTIPLE 134 

OIL BURNERS 1152 

OPENINGS, IN MASONRY WALLS 1411-h 

IN FLAT SLABS 2667 

FLOOR OR ROOF, not covered by trap door to have railing 

30 inches high 1501-b 

ROOF 1501-d 

FOR VENTILATING SHAFTS 1505 

FOR WALLS, percentage allowed according to fire resistance 1302 

OUTSIDE FINISH 1402-d 

PASSAGEWAYS from a building 1805-h 

PAINTING STEEL AND IRON 2816 

PANIC BOLTS 305-k 

PARAPET WALLS 1413, 1414, 1415, 1701-e 

PARTY WALLS 1401, 1405-g,j 1406-h 

IN BUILDINGS OF TYPES III, IV, VI, To extend through 

roof 1405-j 

TO HAVE FIRE DOORS 1901-a,c 

PARTITIONS, BETWEEN ADJOINING APARTMENTS, 1-hour fire resistant, 1001-e 

Covered with acoustical material in Type II 1603-f 

PASSAGEWAY 1805 

PASSENGER ELEVATORS ENCLOSURE DOORWAYS 1503-f 

PEDESTALS, PLAIN 2685 

PENALTIES, For violation of Code 122 

PENTHOUSES 2002 

PERM ITS, Applications for 1 10-a 

May be revoked 111-d 

Shall become invalid 11 1-d 

PHOTOGRAPHIC STUDIO SKYLIGHT 1903-b 

PIERS 2907 

MASONRY 1409 

PILE CAPS 2907-f 

REINFORCEMENT in cover for 2907-f 

LOADING TEST 2917 

PILES, GENERAL REQUIREMENTS 2908 

INSPECTION OF, WHILE DRIVING 2909-h 

PIPE AND CONDUIT EMBEDMENT 2202-g, 2628 

(311) 



Section 

PLASTER AND MORTAR 2202, 2402 

PLUMBING FIXTURES AND UNITS 3114 

DEVICES PROHIBITED 3121 

AND HEATING (Group H Buildings) 1009 

POINT OF INFLECTION in flat slabs 2660 

in reinforced concrete beams 2637 

POLICE STATIONS 801-c 

PORTABLE FIRE EXTINGUISHERS 3008-b 

POSTING FLOOR LOADS 114 

POWERS AND DUTIES OF THE BUILDING COMMISSIONER 116 

Buildings to be made safe or removed 116-d 

Commissioner can order any alteration on a Pre-Code building if not specif- 
ically covered by Code - 1 16-g 

Condemn any unsafe building ....... 116-d 

Enter any building or premises in line of duty 116-a 

Examinations of dangerous buildings 116-h 

Exits satisfactory to Commissioner 116-d, 1802-d 

Fine for hindering the Commissioner 116-d 

Inspection of gas fixtures 1 16— i 

Opening in fire wall — Commissioner may vary 1302-h 

Provisions of Section 116 to apply to Pre-Code buildings 116-k 

Rules and regulations 1 16— j 

Substitution of materials and methods 116—1 

Work may be stopped 116-b, 1302-b 

Working stresses may not be altered by Commissioner 116-1 

PRECAST CONCRETE PILES 2911 

PRE=CODE BUILDINGS 107, 116-g,k, 124-c, 1414 

ENLARGED IN AREA OR NUMBER OF STORIES 107-f 

MOVED TO ANOTHER LOCATION 107-e 

OF GROUP "C" (Schools), To conform to new code 501-g 

SECTIONS WHICH APPLY TO 107-b 

TO HAVE ELECTRICAL FIRE ALARM SYSTEM 107-e 

SAFE EGRESS 107-e 

PRESSURE RELIEF VALVE 3114-d 

PROJECTION ROOM 314 

PROTECTION OF STRUCTURAL STEEL 2202-d 

AGAINST CORROSION 2816 

PROTECTIVE COVERING OF REINFORCEMENTS 2627 

PROPERTY LINE, walls less than ten feet from, two-hour fire resistant 1003-a 

PROSCENIUM 310 

RAILING, BALCONY 2309 

RAIN WATER, Discharged from cornices or copings on a public way 1703-a 

Drains to be laid not lower than four feet below street grade 3105 

RANGE HOODS 2114 

RAT-PROOFING 1608, 1902-i 

RECESSES, CHASES AND CORBELS 1411 

REDUCTION OF LIVE LOAD 2310 

REINFORCED CONCRETE WALLS 1405 

MASONRY 2415 

REINFORCEMENTS, in concrete exposed to weather to have two-inch cover. . . 2627-a 

REMOVAL OF WATER FROM EXCAVATION 2617 

RESTAURANTS, RETAIL STORES, ETC. one person for every 15 square feet, 1803 

RETAIL STORES 901 

Stairways and ramps serving basement only 804-c 

REVIEWING STANDS 203-c, 1204-a 

REVOLVING DOORS 1806-f 

RIBBED SLABS 2653 

RIVET CONNECTIONS 2809 

RIVETS 2815, 2817-c 

ROOF CONSTRUCTION, roofing 107-g, 1417-f , 1700, 2003, 2217 

COVERING 2217 

DRAINAGE 1703 

of Marquees 1703-c 

FILLINGS, For drainage of future floor in Type I or Type II may be of 

wood 1701-c 

(312) 



Section 
ROOF GUTTERS, CORNICES, ETC., In Types I, II, III and IV buildings 

outside fire limits may be of wood 1402-d 

LOADS 2311 

PROJECTION, Maximum of 12 inches to form eaves, except in first or 

second fire zones 1701-e 

ROOFS SHALL BE SLOPED, To drain at a pitch of not less than 1 inch in 10 feet, 1703-a 

ROOMS IN APARTMENTS, Minimum 70 square feet of floor area 1007-a 

LIGHTING AND VENTILATION OF, 606, 706, 806, 906, 1006, 1106, 1206 

MINIMUM HEIGHT, 8 feet i 1007-b 

RULES AND REGULATIONS, For tearing down buildings 116-j 

SALVAGED LUMBER 2504-f 

SCHOOLS (see Part 5-Group C) 

SCOPE OF CODE 107-a 

SECOND-HAND MATERIALS, MASONRY 2416 

STRUCTURAL STEEL 2802-c,d 

SEPARATION, ANGLE OF 1301-g 

BETWEEN FIRE DIVISION WALLS 1302-g 

OF OCCUPANCIES (see Group— Occupancies), also 134, 1301, 1302 

SHOW WINDOWS IN A STORE 1902- j 

SIDEWALK LIGHTS 1904 

SIGNS, EXIT 1818 

FLAT 1201-c 

SKYLIGHTS 1903 

In stair enclosures in roofs 1501-b, 1503 

Parts exposed to weather to have wire glass 1903-e 

Ventilation 1006-c 

SLABS, Two-way 2654 

SLEEPING ROOMS 1006-a, 1106 

Floor and walls on ground 1007-c,e 

SLENDERNESS OF BEAMS. 2647 

SMOKE PIPES 2106 

PROOF TOWERS 1810 

STACKS 2105 

SOIL AND WASTE PIPE 3104 

BEARING FOR FOUNDATIONS 2904 

PIPE not to be less than four inches diameter 3104-e 

SPANDREL BEAMS 2651 

SPECIFICATION, Of steel and iron 2802 

SPIRAL COLUMNS 2671 

STAIRS, Not to be used 1808-j 

SPLICES, In reinforcements 2626 

Lapped in longitudinal reinforcements .- 267 1-c 

SPREAD FOOTINGS, not to be supported on fill 2902-a 

SPRINKLERS 

Definitions 106 

Group A 313 

Group B 411 

Group C 509 

Group D 607 

Group E — Higher than two stories or 10,000 feet 707-a, 1 

Cellars and basements, floor area 1,500 square feet 707-a, 2 

Certain manufacturing plants 707-a, 3, 4, 5 

Group F — Cellars and basements more than 1,500 square feet 807 -a 

Divisions 2 and 3 — -six or more stories 807-b 

Division 4 — Types III, IV and VI on wharves 5,000 square feet.. . 807-c 

I, II and V 20,000 square feet 807-c 

Garages to have sprinklers if more than 10,000 square feet 807-f 

Group G — -Cellars, basements, Divisions 2 and 3 — more than 1,500 square feet, 907-a 

Divisions 2 and 3 of Type IV, 7,500 square feet 907-b 

Group H — Cellars, basements, Types I and II — six stories high 1008-a 

All others more than three stories 1008-a 

Group I — Cellars, basements in buildings more than six stories 1 107-a 

Fire windows, exterior wall — Commissioner may allow ordinary windows 

with sprinklers 1902-g, 2216-i 

In pre-code buildings, Group E and F, or either, in combination with Group 

H or I 3001-b 

Multiple Occupancies if building is more than three stories — first floor for com- 
mercial and more than two families above second floor 1301-h 

(313) 



Section 
SPRINKLERS— Continued 

CONTROL 3006 

Construction of 3001-a,d 

OBSTRUCTIONS, Not to interfere with sprinklers 3006-a 

One of the enclosed corridors in the first floor may be omitted provided the 

basement and first story are equipped with automatic sprinklers 1805-d 

STAIR LANDINGS in school buildings 505 

STAIRS, Group A — Rise not to exceed 7 1/2 inches. Tread not to be less than 
10 1/2 inches. Flights not more than fifteen nor less than three be- 
tween landings and winders 305-m,n 

STAIRS, Product of tread and rise to be not less than 70 inches nor more than 77 

inches except in schools 1808-h 

Rise and tread 7 1/2 inches and 10 inches and not more than 15 steps. . 505-g 

RISERS not more than fifteen nor less than two in flight 1808-i 

SPIRAL not to be used 1808-j 

TREAD not less than 9 1/2 inches and rise not more than 7 3/4 inches 1808-h 

STAIRWAY CLOSETS 1808-n 

ENCLOSURES (see Group — Occupancies, also) 1503-b 

INTERIOR, to extend to roof 1808 

LANDINGS, To have no obstruction 1808-m 

Over eight feet wide to have a central rail 305-p 

Railing design 2309-e 

To be enclosed 1004-b 

STANDPIPES 1008-b 

FIRE DEPARTMENT 3002 

FIRST AID 3003 

STEEL AND IRON (Part 28) 2801 to 2820 

Beams and girders 2808 

Beams encased in concrete 2650 

Columns 2807 

Connection details 2809 

Construction workmanship 2815 

Deck floors and roofs 2820 

Frame 2814, 2815 

Frame walls 1416 

Frames not to be supported on wood 1416-g 

In reinforced concrete exposed to weather, two-inch protection 2627 

STEEL Joists 2818, 2820 

Not to be used in first floor of certain buildings 2818-c 

Member, minimum thickness 2813 

PIPE : 3117 

STIRRUPS, Hangers not less than 3/16 inch thick 1604-e 

STONE 2202, 2404, 2405 

STORE FRONTS 1902-j 

STOVES AND RANGES 2113 

STRESSES, Working, Commissioner may not alter 116-1 

IN 

Cast iron 2805 

Cast steel 2804 

Concrete 2629, 2630 

Concrete, due to wind 2631 

Due to short period loading 2504 

Gypsum concrete 2701 

Masonry 2413 

Steel 2803 

Steel, due to wind 2812 

Temperature stresses 2504-a 

Wood 2504 

Wood, due to wind 2504 

STRUCTURAL STEEL, Used in one building, not to be used in another building, 

without the permission of the Commissioner 2802-d 

Members in pre-code buildings prior to 1924 not to be 
stressed in excess of 8/10 of allowable stresses, and 
those of 1924 and prior to 1943 not to be in excess of 

9/10 of allowable stresses 2802-c 

STRUCTURES NEAR AN EXCAVATION 2901 

SUPPORT, For drainage systems 3119 

TABLE OF STRESSES 2629, 2630 

MINIMUM DIAMETERS FOR FIXTURE TRAPS 3115-e 

TANKS ON ROOFS 2003 

TEMPERATURE RELIEF VALVES 3114-e,f 

(314) 



Section 

TEMPORARY STRUCTURES 203-c, 2504-g 

ERECTED IN FIRE ZONES 203-c, 1201-c 

To be removed in one year 2504-g 

TENTS, REVIEWING STANDS, ETC. IN EITHER FIRE ZONE 1201-c 

TEST PITS AND BORINGS 2903 

TESTS FOR LOADS ON BEARING MATERIALS 2915, 2916, 2917 

OF FIRE EXTINGUISHING APPARATUS 3009 

MATERIALS 2604, 2612, 2613 

THEATRES (Part 3-Group A) 301 

AND MOVING PICTURE HOUSES 301, 401 

THICKNESS OF METAL IN STRUCTURAL STEEL 2812, 2813 

THRESHOLDS, To be of incombustible material 1402-e 

Shall not be over one inch high 1806-c 

TIED REINFORCED CONCRETE COLUMNS 2672 

TILE, GYPSUM 2408 

TOILETS, Accommodations and plumbing 3101-b 

Accommodations for schools ' 511 

Floors of, to be tile, terazzo, etc 1007-d 

Minimum size, 33 inches wide; 15 square feet area 1007-a 

No wood work 1007-d 

Number in each apartment 1009-b 

Windows not less than 1/8 floor area 1006-a 

TOWERS, FIRE OR SMOKEPROOF 1810 

TRANSFER BY OWNER OF HIS RIGHTS AND RESPONSIBILITIES 106-d 

TRAP DOORS 1502 

TRAPS, For waste pipes of plumbing fixtures 3108 

TREADS AND RISERS 1808-f 

TRUSSES, WOOD 2509 

TWO-WAY SLABS (reinforced concrete) 2659 

TYPES OF CONSTRUCTION 125 

TYPE V, NOT TO BE USED FOR GROUP H OR 1 1001-b, 1101 

VI, FOR NOT MORE THAN FOUR FAMILIES 1001-f 

VI, MOVING OF, to different location 107-h, 203-d 

VI, NOT TO BE USED FOR MORE THAN SIX-CAR GARAGE. 801-b 

UNIT COMPRESSIVE STRESS IN MASONRY 2413 

STRESS IN WOODEN STRUCTURAL MEMBERS 2504 

URINALS, Plumbing 3113-i 

Multiple type 3115-c 

USE OF STAIRWAY ENCLOSURE AREAS 1507 

USED BUILDING MATERIALS 

Lumber 2504-f 

Structural steel 2802-d 

UPWARD PRESSURE DUE TO LATERAL AND UPLIFT FORCES IN 

ADJACENT SOILS (taking weight of soil as dimin- 
ished by buoyancy, plus full hydrostatic pressure) . . . 2309-a 

UPWARD PRESSURE of water in structures below grade 2309-b 

VACUUM RELIEF VALVES 3114-g 

VALIDITY (Part 32) 

VENEER MASONRY 1405-h, 1415-b 

VENT, Water closet and urinal 1505, 3104-b 

VENT PIPES, to extend above roof 3110 

Size of, for water closets, urinals 3110-h 

VENTILATING DUCTS 1506 

SHAFTS for kitchens, etc 1004-a, 1006-c, 1505 

VENTILATION IN ASSEMBLY HALLS 408 

VENTILATING SHAFTS 1505 

AND LIGHT 806, 1106 

LIGHT IN GROUP H BUILDINGS 1006 

IN KITCHENS 1006-a,d 

MECHANICAL 1006-d 

UNDER FIRST FLOOR WITHOUT BASEMENT .2507, 2818-j 

VENTING 3109 

VERTICAL OPENINGS 1104, 1500 

Protection of 1104, 1500, 1502 

Railing 1501 

Trap doors 1502 

SHAFT AND FLOOR OPENINGS 1004-a,c 

(315) 



Section 

WALLS AND PARTITIONS 1401, 1405 

Existing masonry 1414 

COVERED WITH ACOUSTICAL MATERIAL, 1603-f 

OF CONCRETE 1405, 2678 

OF WOOD 2508 

EXTERIOR, Wooden frame 1417 

FACING A COURT 1402-c 

FOUNDATION, OF MASONRY 1412 

REINFORCED CONCRETE 1405-e 

LATERAL SUPPORT OF 1403 

MASONRY 1406, 1412, 1414 

OF WOOD in basement 1607-b 

Non-bearing, exterior 1406-g 

OPENINGS IN 1302 

FOR DOORS AND WINDOWS IN PARTY 1901 

OPENINGS FOR DOORS AND WINDOWS IN PARTY 1901 

REQUIREMENTS 1402 

STEEL FRAME 1416 

WAR PROVISION (Part 33) 

WASTE FROM HOSPITALS or other indirect waste 3106 

PIPES IN GROUND, not to be less than three inches in diameter .... 3104-f 
STACKS SERVING LAVATORIES, to be three inches in diameter, 3104-g 
FOR SLOP SINKS OR URINALS, to be four inches in 
diameter 3104-g 

WATER CLOSET BUILDING DRAIN 3104-b 

AND PLUMBING 3113-i 

MULTIPLE TYPE . . . . 3115-c 

VENTILATION, need not have windows 1006-c,d,h 

WATER FROM EXCAVATION 2617, 2901 

HEATERS 2112 

SUPPLY 3113 

TANKS ON ROOFS 2003 

WATERPROOFING IN BASEMENT 2902-e 

OF BOILERS OR FURNACES, to be protected against 

damage 2902-e 

OF WALLS OR FLOORS of sleeping or living rooms in 

contact with ground 1007-c 

WEIGHT OF ELEMENTS OF CONSTRUCTION 2303 

WELDING 2809-r 

WHOLESALE STORES '. . . 801-a 

WIDTH OF CORRIDORS AND PASSAGEWAYS 1805-a,b 

WIND LOADS 2312, 2631 

PRESSURE on signs 2312-d 

on walls 1402-b 

STRESSES in concrete 2631 

in steel 2812 

in wood 2504 

WINDOWS 1006-b, 1402-d, 1902 

AS EXITS 1807 

AS SUBSTITUTE for fire doors 1302-i 

FRONTING UPON OPEN SPACE or ventilating shaft 1006-c 

IN EXTERIOR WALL OR ELEVATOR SHAFT, to be protected by 

metal bars 1902-h 

Kitchen area 1006-a 

Toilet area 1006-a 

To open on open space 1006, 1106 

WIRE GLASS IN FIRE RESISTIVE WINDOWS 2216 

LATH 2202 

SCREENS OVER SKYLIGHTS 1903 

WOOD 

Design 250)1 

Floors and roofs 2507, 2508 

Nailing strips . 2506-j,k 

Notches in wooden beams 2506 

Stirrups, hangers 1604-e 

Stresses 2504 

Trusses 2509 

Wooden columns on concrete or masonry 2505-g 

Wooden framing 2509, 

(316) 



Section 

WOOD BEARING PARTITION NOT TO SUPPORT FIRST FLOOR 1607-b 

WOOD FLOORS AND ROOFS 

Floor boards and planking not to penetrate a party or fire wall 2507-c 

Not to be used in first floor and where there is no basement 2507 

Rough floors to be at an angle of not less than 45 degrees 2507-b 

WOOD FRAMING, Bolts, washers and nuts 2509 

Timber joints 2509-b 

FRAME WALLS, EXTERIOR 1417, 2508 

NEAR CHIMNEYS AND HEATING APPARATUS 2104 

NOT TO BE USED FOR FOUNDATION 2501-d, 2907 

WORKING PLANTS 701-a 

WOODEN BEAMS 2506 

Bridging 2506-e 

Built-up beams •.•••: 2506-g 

Joists and headers to be hung in stirrups 2506-d 

Joists to be doubled under partitions 2506-f 

Nailers may be spiked if live load under 40 lbs. per square foot 2506-j 

Nailing strips on steel girders 2506-k 

Notched at end supports 2506-b,c 

Resting on masonry to be separated 2506-1 

Resting upon masonry walls 2506-i 

That meet at columns 2506-h 

WOODEN COLUMNS 2505 

Wood shall not be used for columns in basement 1604-d, 1607-b 

WOODEN FRAME FLOOR CONSTRUCTION 1607 

JOISTS MAY REST ON CLEATS 2506-j 

AND RAFTERS NOT TO EXTEND BEYOND exterior 

wall 1701-e 

JOISTS OR BEAMS THAT FRAME INTO EXTERIOR or party 

walls 1405-j 

MEMBERS UNDER ROOFS of Types III, IV, VI, not to extend 

across exterior walls 1701-e 

WOODEN PARTITIONS 1417, 1607-b 

PILES 2910 

STRUCTURES 

GROUP B— If less than 5,000 square feet (I story) may be Type VI, 401-b 

Exterior walls of wood to be more than ten feet from lot line 403-a 

Exterior walls of wood to be more than 20 feet from combustible 

wall or roof on further side of street 403-b 

GROUP C — If less than 5,000 square feet (1 story) may be of Type 

VI 501-b 

Pre-Code building, two stories, 4,000 square feet, may be of 

Type VI 502-g 

See above for wood walls 503 

GROUP D— If less than 2,500 square feet and one story, Type VI. . 601-b 

See above for wood walls 603 

GROUP E— For Type VI, see table 701-b 

See above for wood walls 703 

GROUP F— For Type VI, see table 801-b 

Garages over six cars — No Type VI allowed 801-a 

No buildings of Type VI on wharves 801-d 

See above for wood walls 803 

GROUP G— See table for Type VI 901-b 

For exterior walls to lot line, etc 903 

GROUP H— See table for Type VI 1001-b 

Exterior walls less than ten feet from lot line 1003-a 

Exterior walls less than 15 feet from another building, etc 1003-b 

GROUP I— Type VI, three stories, 5,000 square feet 1101-b 

Exterior walls more than five feet from lot line 1 103 

GROUP J — Garages for six cars or less, two stories in height, less 

than 1,300 square feet, no Type VI allowed 1201 

Garages for three cars or less (one story), not more than 600 square 

feet, may be Type VI 1201 

Walls, Type VI, and floors and ceilings — every hollow space to be 

fire-stopped 1402-a 

TYPE VI buildings in first fire zone 203-b 

TYPE VI buildings in second fire zone 203-d 

WALLS NOT TO BE USED FOR PARTY, FIRE OR ENCLOSURE 

WALLS, or when required to have more than one-hour fire 

resistance 1417-a 

WORKMANSHIP IN STEEL CONSTRUCTION 2815 

CITY OP BOSTON a ^^^> PRINTING SECTION