Square footage is the number a property is priced on, and it is also one of the most commonly disputed. Part of that is bad measurement. Part of it is that "square footage" means something specific, and people add up different things.
The scan gives you the areas
A whole-house capture produces floor area per room, per level, and in total, with real wall positions behind each number. That is the measurement problem solved to about an inch — which is tighter than the tolerance most square-footage disputes are about.
The standard decides what counts
ANSI Z765, which most lenders and MLS systems reference, has rules the scan does not apply for you:
- Finished versus unfinished — an unfinished basement is not living area
- Below grade is reported separately, not folded into above-grade GLA
- Ceiling height minimums — low-sloped areas under seven feet are excluded or limited
- Garages, porches, and unfinished attics are out
- Exterior versus interior measurement — the standard measures to exterior walls, so an interior room-area sum needs the wall thickness accounted for
That last one is the detail that trips people up. Interior room areas and ANSI GLA are different quantities, and the gap is the walls.
Which makes the scan the input, not the answer
Use the per-room areas and heights as the measured basis, then apply the standard's rules to decide what to include and how to report it. The scan's contribution is that every room's area and ceiling height is real, including the sloped ceilings where the height rule actually matters.
Where it is immediately useful
Listing agents checking a suspicious tax-record figure before publishing it. Appraisers wanting a measured basis on an irregular house. Owners contesting an assessment. In each case the argument improves when the geometry is not in question.
And for the record
An appraisal is still an appraiser's work. This measures the building.
The number is only defensible if someone measured the rooms.