Dearborne's 8th Edition text - Fundamentals of Real Estate Appraisal, says the following about GLA & GBA: "Gross living area. For a single-family detached residence, size is described in terms of gross living area (GLA), defined as the total amount of finished habitable above-grade space, measured along the building's outside perimeter. Generally, attics, basements, and crawl spaces are not included in the measurement." "Gross building area. For multifamily residences and industrial buildings, size is described in terms of gross building area (GLA), defined as all enclosed floor areas (including both attics and basements), measured along the building's outside perimeter." My questions are ... 1. Does the GBA definition apply to 2-4 family rental properties? 2. When researching comparable properties (2-4 family and 5+ family) at the assessor's office, is it unreasonable to expect that the assessor has switched from the GLA to GBA definition in making square footage caculations?