ANSI Z765-2003 - VOLUNTARY STANDARDS
This standard for the calculation and reporting of above-grade square footage and below-grade square footage in
single-family houses is offered for voluntary application. The standard must be applied as a whole. The standard is
not meant to replace or supersede any legal or otherwise required existing area measurement method.
Ceiling Height Requirements
To be included in finished square footage calculations, finished areas must have a ceiling height of at least 7 feet
(2.13 meters) except under beams, ducts, and other obstructions where the height may be 6 feet 4 inches (1.93
meters); under stairs where there is no specified height requirement; or where the ceiling is sloped. If a room’s
ceiling is sloped, at least one-half of the finished square footage in that room must have a vertical ceiling height of
at least 7 feet (2.13 meters); no portion of the finished area that has a height of less than 5 feet (1.52 meters) may
be included in finished square footage.