Institute of Housing Technologies
Improving the Real Estate Information Network
The American Measurement Standard
The American Measurement Standard (AMS) is a voluntary, authoritative, guideline for measuring residential square footage. Home measurement basics, which provide acceptable measurements for the VA, FHA, HUD, Fannie Mae and Freddie Mac. It contains more than three times the information on measuring a single-family home than any other national guideline available today. The techniques described are an accumulation of research contributed by professional Realtors®, appraisers, home builders, and architects, and are the same principles used by leading national designers and architects. It is widely used and recognized throughout the real estate industry. A long standing tradition with modern sensibility. Square footage provides the currency of real estate and consumers should be protected by one national measurement standard. Updated for 2018.
The AMS is similar to the ANSI Standard with one exception being the ways stairs are measured and counted. The method within the AMS is taught to many real estate professionals across the country. These pros have been taught that on the second level, if you can't walk on it, you can't count it. The same way many builders looks at uppers levels and square footage. The key is to follow one standard and include the method followed in a disclosure every time you provide a square footage total for others. It's just a smart business practice. Know the "Standard" you follow and be consistent...
This method has been in use over a CENTURY!