The BOMA Standards
BOMA (Building Owners and Managers Association) developed a standard for
measuring floor area in 1915. Since then, the BOMA system has become
a popular industry standard. The latest revisions, in 1980 and 1996
are the basis for determining rentable areas in the majority of office
buildings throughout North America. The standard is applicable to both
new and existing office buildings and allows for a comparison of values
on the basis of an agreed upon method of measurement
Most property managers and owners choose BOMA because it is the industry
wide standard on which rentable areas are based, allowing their buildings
to be compared to others. More importantly, using BOMA gives the property
manager the ability to capture all areas in the building as rentable
space, including common building lobbies, mechanical areas, services
rooms, etc. This usually results in an increase in rentable area, which
in most cases, easily offsets the cost of the actual building survey.
BOMA 1996 vs. BOMA 1980
The latest revision to the BOMA standard (1996) has introduced the commercial
real estate world to a new way of measuring office buildings on a building
wide basis as opposed to a floor by floor basis.
In the 1980 method, rentable area was calculated per tenant in respect
to that tenants usage on any one particular floor. The useable area,
meaning the actually occupiable area of a floor, is increased by the
floor common area, or the tenants proportionate share of the floor common
area, to achieve the rentable area.
The most significant change in the 1996 method includes the inclusion
of building common area in each tenant’s rentable area. Just as
the useable area is increased to support the tenant share of the common
area on their floor, that figure is again increased by the tenant’s
proportionate share of the building common areas. These areas include
main floor lobbies, storage rooms and building service rooms, all of
which where not included in the rentable areas when using the previous
The BOMA standards are created to apply to office buildings only. Although
the basic concepts are often implemented into leases of other building
types, the standard does not recognize them.
Retail and industrial buildings are most often measured from the outside
face of exterior walls and the center of demising walls, with no increase
or gross-up factors for common areas.
Government and residential buildings can vary from this as well. The
methods of measurement are unlimited to whatever any one lease may
If you would like further information on the BOMA standards, the definitions
used, and answers to FAQ, refer to the BOMA website at www.boma.org