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Determining the leased area: measurement standards

In commercial leasing, it is common for rent to be determined primarily on a space-based rate per square metre (m2) or per square foot (ft2). For this reason, it is important for the parties to use a recognized method of measuring the leased area. The BOMA (Building Owners and Managers Association) standard is one of the most widely used and the only one approved by the American National Standards Institute (ANSI).

BOMA’s measurement methods have, over time, been the subject of several standards adapted to different types of leased properties such as office, industrial, retail, multi-unit residential, or mixed-use immovables.

The use of a measurement standard allows for uniform calculation of the leasable areas used to determine rents, since this is most often determined by the area actually occupied by the lessee, to which is added a proportional share of common areas (lobby, stairwell, elevator, etc.). These common areas can represent up to 30% of the total space of an office building, but usually much less for an industrial building.

It is important to know that the calculation methods vary depending on the BOMA standard used, the type of building or the year of publication of the standard. To avoid disputes, the parties must agree on the standard used to determine rent. It is in the interest of the prospective lessee’s broker to require that the leased space be measured within a specific time frame, according to a specific standard, and confirmed by a measurement certificate. It may be difficult for his client to challenge a rent based on an incorrect measurement if he has agreed to the terms of the lease without first making these verifications.


Last updated on: December 16, 2022
Reference number: 264733