BOMA Standard Methods of Measurement: considerations for landlords and tenants

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The Building Owners and Managers Association (BOMA) developed and maintains the most commonly used measurement system for office space, among other types of buildings. As the American National Standards Institute (ANSI) Secretariat for the standard of floor measurement, it is BOMA’s responsibility to provide area measurement standards that provide consistent measurement rules for rentable square footage, thereby allowing accurate comparisons and clear communications among all participants in a real estate transaction.

The BOMA Office Building Standard Methods of Measurement were last updated in 2017; the methods are reviewed at least every five years to stay current with the changing needs of the commercial real estate market.  The 2017 Office Standard contained major updates to both how square footage is measured, and two modifications in how square footage is allocated. Further, starting with the BOMA 2017 Office Standard, BOMA’s measurement concepts and methodologies are now in alignment with the International Property Measurement Standards.

Square Footage Measurement

Balconies, terraces, and roof spaces now rentable

Useable outdoor spaces have proven to be a desirable user amenity. The BOMA 2017 Standard includes finished rooftop terraces (emphasis on “finished”), balconies, and covered galleries that are designated for a tenant’s exclusive use to be included in square footage calculations. Since these areas were not included in earlier BOMA Standards, the 2017 modification could increase the total square footage in existing buildings. Landlords and tenants alike will want to make certain what Standard was used in order to know what is included in the rentable square footage. 

All lowest-level vertical penetrations included

Another change that may increase landlord revenue pertains to the vertical penetrations in multi-level buildings. BOMA 2017 now includes the floor area associated with the lowest level of all major vertical penetrations (stairs, elevators, escalators, flues, pipe shafts, and vertical ventilation ducts) in square footage calculations.

Public thoroughfares excluded

This change in the Standard may decrease the amount of rentable square footage in existing buildings, as the “public pedestrian thoroughfare boundary condition” is no longer applicable. Per BOMA 2017, the square footage of street-facing, ground floor office space is measured from the inside finished surface of the wall. The resulting calculation may result in slightly less rentable square footage. Even so, landlords of multi-floor office buildings may see a net increase of square footage resulting from the first two modifications.


Allocation of Square Footage

Shared Amenity and Service Areas

The term used in the Standard is “Inter-Building Area”, and it refers to the amenity and service areas that are available for all building tenants. BOMA 2017 now includes a method to allocate the square footage of these area to only those tenants that actually use them. For example, if four out of nine tenants on a floor use the common conference room, only those four tenants will be allocated a pro rate share of the square footage of that conference room. The Inter-Building Area allocation allows tenants to only pay for the areas they use

Capped Load Factor

The load factor is the ratio that accounts for all the square footage of common amenity and service areas in an office buildings. Landlords apply the resulting number to each tenant’s private office area. As tenant demand continues to rise for amenities like coffee bars and collaborative work space, the load factor may increase to unmarketable levels. BOMA 2017 allows landlords to cap load factors on a tenant-by-tenant basis, allowing them to still be compensated for all the building’s rentable square footage while having the flexibility to target specific tenants. Leasing agents are now using reduced add-on’s as incentives when tenants are comparing different buildings.

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