Rentable Square Footage (RSF): Do you know yours

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It used to be so simple. Rarely did anyone ask how space was measured.

But commercial real estate has evolved so much over the years that accurate measurements are more crucial than ever. Rent, operating expenses and purchase price are all based on a per-square-foot (psf) basis. With the trend of mixed-use and campus developments, property types are colliding and posing even more complex questions on how to accurately measure space and determine rentable square footage (RSF).

One way to potentially add value to your property is to professionally measure the building. Historical measurements are often incorrect, yet carried forward on CAD drawings, or space is improperly classified in the measurement calculations resulting in faulty rentable square footage. I've seen situations when an entire corridor was not properly reflected on plan, and times when core space was included in a vertical penetration. A metrologist understands the science of measuring. There are many that specialize in the commercial real estate industry; their understanding of building construction and the treatment of blind space, such as vertical and void areas, equips them to dissect a project and discern proven measurement classifications. Pricing is usually $0.03 to $0.01 psf, depending on the services requested. CAD drawings can be provided to the architectural firm upon completion, reflecting any discrepancies to the original drawings on file.

Yet sometimes even metrologists have varying opinions on how to measure space and determine the RSF. That is why the Building Owners and Managers Association (BOMA) International, as the leader iin floor measurements, recognizes official interpreters of measurement standards. These companies have a proven track record, have participated in the development of the standards, and contribute to the industry with their experience and knowledge. Uniformity and consistency area paramount.

BOMA published the first measurement standard in 1915; has updated it several times as the industry has evolved; and has since developed standards for industrial, gross area measurement, facilities, retail, multiunit residential and mixed use properties. These standards are American National Standards Institute (ANSI) approved, and many have been developed in collaboration with other organizations, when appropriate. BOMA developed the Multi Unit Residential Standard in collaboration with the Institute of Real Estate Management, National Multi Housing Council and the National Association of Home Builders. The development group included property managers, owners, metrologists and architects.

It is important to maintain accurate records of building and rentable square footage to protect the value of an asset. These standards provide a guideline for a uniform method of measurement that can be used by real estate professionals, including architects, space planners, interior designers, engineers, building owners and managers, leasing professionals, asset managers, appraiser and other concerned with measurement. If a building's square footage has been determined utilizing BOMA methodology, the method and year of publication should be noted so there are no questions as to the methodology utilized. Calculations are seemed within tolerance if the variance is two percent or less. Note: There is no "modified" BOMA standard.

So when brainstorming on how to add value to your properties, you may wish to add revisiting space measurements to the list, and drill down into the calculations. Who knows? You could add another $100,000 value to your property.

This article was originally published by Rebecca B. Hanner, CPM, RPA and is reprinted here with her permission

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