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Part of: GLA & Appraisal Standards: The Complete Guide

ANSI Z765 GLA Measurement Checklist for Appraisers

A field-ready checklist for measuring gross living area correctly under the ANSI Z765-2021 standard. Use this before, during, and after every measurement assignment to stay compliant and avoid reviewer comments.

Part 1: Pre-inspection prep

If you're preparing a homeowner or buyer for what the appraiser will need, see the companion appraisal prep square footage checklist — it covers what documentation to have ready before the appraiser arrives.

• Review prior appraisals or MLS data for the property. Note the reported GLA. If your measurement differs significantly, you need a documented reason, not a surprise in the report.
• Confirm the ANSI Z765-2021 version applies. Fannie Mae and Freddie Mac require ANSI Z765-2021 for all UAD appraisals dated April 1, 2022 or later. FHA and VA follow the same standard. USDA requires consistent methodology with other lender guidelines.
• Know the property type. Condos, townhouses, manufactured homes, and single-family detached all have slightly different measurement conventions. Flag the type before arriving.
• Check for additions or permits. Recent building permits, additions, or ADUs may not be reflected in prior reports or county records. Plan to walk the full perimeter.
• Bring the right tools. Laser measurer, manual tape as backup, clipboard or tablet for sketching. Floor plan from a prior appraisal if available, to compare, not to copy.

Part 2: Exterior measurement (above-grade levels)

• Measure from the exterior, not the interior. ANSI Z765 requires exterior measurement at the face of the exterior walls. Interior room-by-room measurement will always undercount because it excludes wall thickness. See the full guide on measuring square footage for a real estate appraisal for the complete field measurement walkthrough.
• Confirm each level is above grade before including it in GLA. A level qualifies as above grade only if the finished floor is at or above finished grade on all sides. Check the uphill side on sloped lots, not just the obvious exposed side.
• Sketch each above-grade level separately. Multi-story homes require a separate footprint for each level. Do not assume upper floors match the first-floor footprint, overhangs, setbacks, and partial upper levels are common. See how to measure multi-story home square footage for a level-by-level walkthrough.
• Account for all jogs, bays, and offsets. Measure each projection and recess individually. Sketching as you go prevents omissions. Running totals help catch errors before you leave the property.
• Verify the sketch closes. When the exterior measurement is complete, the running total of horizontal dimensions on one axis should equal the running total on the opposite axis. If it does not close, find the error before leaving.
• Note any attached structures that are NOT GLA. Attached garages, covered patios, and open porches are outside the GLA boundary even if they share a roofline. Mark them clearly on the sketch so they are not accidentally included.

Part 3: Special spaces, verify before including

Finished basements and below-grade areas

• Confirm the level does not qualify as above grade (all-sides test). Below-grade finished area is reported separately from GLA, never combined.
• Measure and record finished vs unfinished below-grade area separately. Note room count (bedrooms, bathrooms) in below-grade finished space.
• For walk-out basements: confirm all sides of the floor level, the walk-out side being exposed does not make the level above grade if other sides are below grade.

Attics, bonus rooms, and sloped-ceiling spaces

• Apply the 50% ceiling height test: at least 50% of the finished floor area must have 7 feet or more of ceiling height for the space to qualify as GLA.
• Areas with less than 5 feet of ceiling height cannot count under any circumstance, regardless of the 50% test result.
• Verify access via fixed interior staircase. Pull-down attic stairs are a strong exclusion signal.
• Measure the qualifying (7+ foot) floor area separately from the total floor area. Record both figures for documentation.
• For bonus rooms above garages: confirm interior access from the main dwelling (not just through the garage), above-grade floor level, and ceiling height compliance.
• Cape Cod upper floors require extra attention: the kneewall height and roof pitch determine how much of the upper level qualifies. Measure the qualifying floor area to the 5-foot ceiling line and apply the 50% test to that reduced area.

ADUs and secondary units

• Detached ADUs are never included in the subject property's GLA regardless of finish quality. They are reported separately as accessory structures.
• Attached ADUs with shared interior access to the main dwelling may be includable in GLA if above grade and meeting all other criteria. Verify access and grade compliance. See the in-law suite square footage guide for how appraisers handle attached secondary units.
• See ADU square footage guidelines for Fannie Mae reporting requirements.

Garages, porches, and outdoor structures

• Garages are never GLA, attached, detached, or converted. Converted garages retain their non-GLA status unless fully integrated with permitted conversion (and even then, consult local lender guidelines).
• Open porches, covered patios, and decks are not GLA. Screened porches are not GLA. Only fully enclosed, heated, finished space connected to the main living area qualifies. See the deck and porch square footage appraisal guide for how these features are valued and reported.
• Sunrooms may qualify if they are fully enclosed with insulated walls and connected to the main HVAC system. Verify carefully, three-season rooms typically do not qualify.

Part 4: Sketch and documentation requirements

• The sketch and sketch addendum must show the shape and dimensions of each above-grade level, with GLA labeled per level and a total GLA figure.
• Below-grade finished area must be shown on the sketch separately with its own dimensions and square footage, not combined with above-grade GLA.
• Garages, attached structures, and non-GLA areas must be dimensioned on the sketch and labeled (e.g., "2-car garage: 480 sf").
• If any attic or sloped-ceiling space is included in GLA, note the ceiling height compliance in the report addendum: "Ceiling height of 7 feet or more confirmed over [X]% of the floor area, meeting ANSI Z765-2021 requirements."
• If any space is excluded from GLA for a non-obvious reason (e.g., detached ADU, pull-down attic access), note the reason in the addendum.
• Verify the sketch GLA total matches the GLA entered in the report form. Mismatches between sketch and form are a common reviewer flag.

Part 5: Final GLA verification

• Cross-check your GLA against the prior appraisal or MLS. A difference of more than 3-5% needs a documented explanation. Common causes: prior appraiser used interior measurement, ANSI Z765 was applied differently before 2022, unpermitted additions, or different attic/bonus room treatment.
• If your GLA is significantly lower than Zillow or the county assessor, that is expected, those sources often use different methodologies, interior measurements, or outdated data. No explanation needed in the report, but be prepared for borrower questions.
• Confirm your comparable GLA figures were sourced consistently. If you measured the subject exterior, verify that comparable GLA was also measured exterior (or note the limitation if you used MLS GLA for comps).
• Review the GLA adjustment for comparables. It should be market-derived, not a default per-square-foot figure. Confirm it is supported by paired sales analysis in the report.

Quick reference: what counts as GLA vs what does not

Counts as GLA

• Above-grade finished living space (all sides at or above grade)
• Finished attic with 7+ ft ceiling height over 50%+ of floor area, fixed stair access
• Attached ADU with interior access from main dwelling (above grade)
• Sunroom that is fully enclosed, insulated, and connected to main HVAC

Does NOT count as GLA

• Any below-grade level (including walk-out and daylight basements)
• Garages (attached, detached, or converted, absent permitted conversion per lender)
• Detached ADUs and guest houses
• Open porches, covered patios, screened porches, decks
• Three-season rooms and unheated sunrooms
• Attics accessed only by pull-down stairs
• Storage rooms without finished walls, flooring, and ceiling
• Utility rooms accessible only from outside the main living area

Related Resources

• ANSI Z765 Square Footage Standard: What Counts as GLA and What Gets Excluded
• How to Read a Floor Plan for Square Footage: Scale, Symbols, and Calculations
• Loft Square Footage in Appraisals: When It Counts as GLA and When It Doesn't
• Garage Conversion Square Footage: Does It Add to Your Home's GLA?
• What Is Gross Living Area (GLA)? Definition, Rules, and How It Affects Value
• GLA Calculator for Appraisers: How to Calculate Gross Living Area
• How Appraisers Calculate Square Footage: The Complete Process Explained
• Appraisal Sketch Requirements: What Fannie Mae and FHA Require
• How Appraisers Adjust for Square Footage Differences Between Comparables
• How to Measure Square Footage for a Real Estate Appraisal
• ANSI Z765 vs BOMA: Square Footage Standards Explained
• PlanSnapper vs a la mode TOTAL: Floor Plan Measurement for Appraisers
• The Complete Guide to Home Square Footage: Measurement, Appraisal, and Value
• Modular Home Square Footage in Appraisals: How It's Measured and Reported
• Floor Plan Measurement Tool: Calculate Square Footage from Any Floor Plan
• Floor Plan Measurement Tools: The Complete Comparison Guide
• GLA vs Total Finished Area: Key Differences for Appraisers
• Net Livable Area vs Gross Living Area: How They Differ in Appraisals
• How Accurate Is Redfin Square Footage? What Buyers Need to Know
• FAQ: What Changed in ANSI Z765-2021?
• Bi-Level Square Footage in Appraisals: How the Split Entry Affects GLA
• How Many Square Feet Is an Acre? Land Measurement Explained

Frequently Asked Questions