Square Footage Calculations

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There was a time when one simply assumed that the listed square footage for a property was accurate. Over time though knowing the true square footage of a property, be it a commercial, institutional, educational, or residential structure, has become an important part of any sale. Having accurate square footage calculations protects the interests of sellers, buyers, and tenants during and after transactions and for tax purposes. 

With this evolution in the market one of the questions that comes about is how to conduct the square footage calculations of a given property. Each type of building requires a different measurement standard. Some specific regions have their own standards that are distinct from the national standards. Below is a listing of the most common and court recognized  

First published in 1915 and continuously updated since then, The Building Owners and Managers Association (BOMA) International has created a set of standards for determining the gross, usable, and rentable square footages of commercial office, retail, industrial, multi-residential, and mixed use buildings. The BOMA standards are certified through the American National Standards Institute (ANSI) and have been adopted worldwide. The standards are:  

The International Facility Management Association (IFMA) has published the "E1836-08: Building Floor Area Measurements for Facility Management" measurement standard. Certified by the American Society for Testing and Materials (ASTM) this standard is most appropriate for facilities such as arenas, laboratories, manufacturing buildings, and hospitals. 

Universities and colleges may have their areas determined by either of the above standards or by using the Postsecondary Education Facilities Inventory and Classification Manual (FICM) standard which was created by the National Center for Educational Statistics (NCES) in 2006. 

The Square Footage - Method for Calculating standard was created by the National Association of Home Builders (NAHB) and is certified by ANSI. This standard is used nationwide for single family detached homes. Attached homes such as townhomes, condominiums, and apartments should have their square footage calculated using the BOMA standard.  

Even some regions have their own measurement standards. Until recently the metro Washington, DC area had its own standard but no longer uses it. The Real Estate Board of New York (REBNY) is another example of a regional standard for measuring. 

As you can see the multiple methods for square footage calculations address specific building types. Using one of these documented standards sellers, buyers, and tenants can ensure that they are getting the maximum value while ensuring that the building or space will meet their needs.

As a member of the BOMA measurement standards committee American Building Calculations is uniquely qualified to provide our clients with most precise calculations and maximizing their return on investment. Please visit services page for square footage calcualtions for an example.


Get answers to your BOMA measurement standards questions answered here.

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