Does a cantilevered floor count as square footage?
Published August 27, 2026
Yes. ANSI Z765 measures each floor to its own exterior walls, so a second floor that overhangs the first by two feet is measured to the overhang and the whole floor counts as gross living area. The fact that there is open air or a porch roof beneath it does not matter. A roof overhang or eave with no floor above it does not count.
Measuring an overhang
Because you cannot walk around a cantilevered second floor, the appraiser measures it from inside and adds the wall thickness, or measures the overhang from below. Garrison-style colonials and modern boxes with cantilevered upper floors are the usual cases. They count because ANSI measures the exterior, and a cantilever has an exterior.
What does not count as a cantilever
- Roof eaves and soffits: no floor above them.
- A porch roof or carport under the upper floor: the upper floor counts, the covered area below does not.
- A cantilevered deck or balcony: not enclosed, so it is a deck, not GLA.