EXTERIOR HOUSE DESIGN 179 Proportion is a basic principle that refers to pleasing relationship in line and spaces. In judging the exterior of a house the propor- tion of the whole composition as well as every detail is a matter of concern. Low, broad houses like those on page 190 are more pleasing in proportion than tall houses. One important considera- tion is the relative heights of the foundation, walls, and roof. Only a small amount of exposed foundation is desirable, particularly in a small house. The wall and the roof must not be equal in area as observed from the front walk. Each wall should have pleasing dimensions, like one-third more length than height. Windows and doors suggest definite ideas by their proportions: low, broad windows and doors are informal; high windows and doors are stately. Although traditional double-hung windows are most common, where ventilation is of first importance the most serviceable windows are either the casement type or the modern type with horizontal panels, opening outward to exclude rain. Large floor-to-ceiling windows and bay windows provide more light and more interest than ordinary types. Good proportions can be obtained in all these types. Small windows above fireside bookcases or above a buffet are awkward in proportion; further- more, they do not provide a view and are difficult to curtain. In all moderate-priced houses ready-made windows and doors should be purchased complete with frames and weather stripping for the sake of economy and also for smooth functioning. Scale refers usually to the size of details in relation to the size of the entire house. For example, a small house must have narrow" cornices and moldings, small windows, and fine proportions in doors. Windows, especially dormer windows, are often too large for the places where they are used. Small-paned windows are usually in better scale with a small house than large panes, and they often add charm and give a feeling of privacy. Unfortunately doorways are sometimes too large or too small for the scale of facades of houses. Porch columns may appear too large for the small weight above them. On the other hand, modern columns may appear too small, for we have not yet become accustomed to the fact that slender columns when made of steel can support great weight. One un- broken line from floor to ceiling is desirable, therefore porch columns should not be placed on high bases. See page 191.