Real estate appraisers will be required to use the Square Footage-Method for Calculating: ANSI® Z765-2021 (American National Standards Institute®) Measuring Standard for measuring, calculating, and reporting gross living area (GLA) and non-GLA areas of subject properties for appraisals requiring interior and exterior inspections with effective dates of April 1, 2022 or later for loans sold to Fannie Mae. Click here to view the video provided by Fannie Mae.