Guides · Floor Plan Measurement
GLA stands for Gross Living Area. It's the primary square footage metric used in residential real estate appraisals: the number that appears on the URAR appraisal form, drives comparable sales adjustments, and determines how lenders value a home. Understanding GLA is essential for anyone buying, selling, or appraising residential real estate.
Under ANSI Z765-2021, Gross Living Area is the finished, above-grade, heated and cooled residential living space measured from the exterior walls. Three criteria must all be met:
1. Above-grade: The space must be at or above the surrounding exterior ground level on all sides. A fully finished, carpeted, heated basement is still not GLA if any exterior wall is below ground. 2. Finished: The space must be finished to a livable standard: drywall on walls, flooring, and ceiling at least 7 feet high over the majority of the space. 3. Heated and cooled: The space must be connected to the home's HVAC system. An unheated screened porch doesn't count even if beautifully finished.
Bedrooms, living rooms, dining rooms, kitchens, hallways on above-grade floors. Above-grade finished attic space with 7-ft minimum ceiling height. Heated four-season sunrooms above grade. All above-grade floors of a multi-story home.
Finished basement: Even a fully finished basement with a home theater, bedroom, and bathroom: if any exterior wall is below grade, none of it counts as GLA. It's reported separately as below-grade finished area. Garage: Attached or detached, regardless of heating or finish. Unheated porch or screened porch: Not connected to HVAC = not GLA. Low-ceiling attic space: Below 5 feet doesn't count at all; 5–7 feet counts only as part of a larger finished space. Carport: Not GLA.
GLA is measured from the exterior walls: wall thickness is included. This is why an appraiser's field-measured GLA will be slightly larger than interior square footage measured room-to-room. For a typical wood-frame home the difference is approximately 30–60 sq ft. Appraisers use exterior measurements because exterior dimensions are more consistent and reproducible than interior measurements that depend on wall thickness.
GLA is the unit of comparison in the sales comparison approach. When an appraiser adjusts for size between a 1,800 sq ft subject and a 2,000 sq ft comparable, they're comparing above-grade GLA only. A size adjustment of $50–$150/sq ft means a 100 sq ft GLA error can shift an appraised value by $5,000–$15,000 or more. This is why verifying GLA before listing: not after the appraisal. Matters so much.
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Start Measuring →What does GLA stand for?
GLA stands for Gross Living Area. It is the appraisal industry's standard measurement of a home's residential living space, defined by ANSI Z765 as the above-grade, finished, heated and cooled area measured from the exterior of the walls.
What's included in GLA?
Included: above-grade rooms with at least 7-foot ceilings (over 50 percent of the room area), finished floors, heating and cooling, interior walls, closets, hallways, and stairs. Excluded: basements (even finished), garages, unheated porches, attics with low ceilings, and any unfinished space.
Why does GLA matter?
GLA is the basis for appraisal value, lender underwriting (Fannie/Freddie require it), price-per-square-foot benchmarks, and most listing comparisons. Inconsistent GLA across listings is the single biggest source of pricing disputes in residential real estate.
How is GLA different from total square footage?
GLA is the strict ANSI Z765 figure (above-grade, finished, heated). Total square footage is a looser term that may include basement, garage, or unheated additions. They can differ by hundreds of square feet on the same home.
Who is required to use GLA?
Licensed appraisers must report ANSI Z765 GLA on conventional appraisals (Fannie Mae and Freddie Mac mandate since April 2022). Real estate agents, homeowners, and assessors are not required to use ANSI but increasingly do so to reduce disputes.