In short
- Measure the outside of the exterior walls.
- Only finished area above grade counts.
- Ceilings of at least 7 ft; parts under 5 ft never count.
What the standard says
- Measure to the outside of the exterior walls, in feet and inches or tenths of a foot.
- Count only finished area: floors, walls and ceilings finished like the rest of the house.
- Ceilings need to be at least 7 ft. Under beams and ducts, 6 ft 4 in is allowed.
- With a sloped ceiling, at least half the room must be 7 ft high. Parts under 5 ft do not count.
- Report the total to the nearest whole square foot.
What counts and what doesn’t
ANSI Z765-2021, in our own words
| Space | In the GLA? | Where it goes |
|---|---|---|
| Finished rooms above grade, with closets and halls | Yes | Gross living area |
| Stairs | Yes, on the floor they go down from | Gross living area |
| Any level partly below grade, finished or not | No | Below-grade area, on its own line |
| The finished floor above a basement or crawl space | Yes | Gross living area: each level is judged on its own |
| Garage, attached or not | No | On its own line |
| A room with a ceiling under 7 ft | No | On its own line |
| Parts of a room under 5 ft | No | Not counted |
| Porches, decks and open to below | No | Not counted or on its own line |
Counts
- Finished rooms above grade
- Stairs, on the floor they go down from
- Closets and halls
Reported separately
- Basements: any level partly below grade
- Garages
- Open to below, porches and decks
Example
GLA = 1,200 + 900 = 2,100 sq ft. The garage (440 sq ft) is reported separately.
In Squaremetry
When you measure in feet, Squaremetry counts by ANSI Z765. Every room shows whether it counts and why. A garage or an unfinished room goes under Separate, and the total leaves it out.
Version and sources
- Standard: ANSI Z765-2021, Square Footage: Method for Calculating, Home Innovation Research Labs. Source checked on September 24, 2026.
- UAD 3.6, which reports the area per level in six boxes from these numbers, is mandatory from November 2, 2026 (Freddie Mac Single-Family). See Squaremetry for appraisers.
- Fannie Mae requires it for appraisals with an effective date on or after April 1, 2022.
- Page checked on Sep 27, 2026. We update it when the standard changes.
Related questions
- Does a basement count as square footage?
No. It is reported separately.
- Does a garage count as square footage?
No. It is reported separately.
- Does an attic count as square footage?
Only the finished part, and only where it is high enough.
- Do stairs count as square footage?
Yes, on the floor they go down from.
- Do porches count as square footage?
No. They are reported separately.