Extreme Measures Planmine™ Help Desk
About Us
Sign In / Up

Extreme Measures

This help desk is a free resource intended for discussion purposes only. Neither BOMA, its chapters, affiliates, or Extreme Measures Inc.® are responsible for the information, comments or opinions expressed herein. For complete information, refer to the official publications of the standards themselves.

FAQ & Read-Me Articles
What are as-built drawings / models?
What is CAD and BIM?
How do I resolve an area dispute?
Where can I get measurement standards publications?
BOMA Office Overview
BOMA Industrial Overview
BOMA Retail Overview
BOMA Multi-Unit Residential Overview
BOMA Gross Areas Overview
BOMA Mixed-Use Overview
IPMS for Office Overview
Alternative Methodologies
Glossary of Industry Terms

Building/floor common in floor usable

Mark S
August 31, 2010

I have a question about the 1996 BOMA standard regarding building common vs floor common areas. When calculating floor usable area, building common is included but floor common is subtracted. (correct?) I don't understand why this is so. As a tenant, i can't put employees or furniture within these building common spaces. Why is it still considered part of usable? Am i putting too much emphasis on the tenant when thinking about 'usable'? With a few exceptions, i generally think of usable area as similar to plannable/assignable. Anything you can offer to help clarify my confusion would be appreciated.


David Fingret
Extreme Measures Inc.
August 31, 2010

Hi Mark,

Floor Common Area is not subtracted from Usable Area, it's just not included. Building Common Area is considered Usable Area because like Tenant Areas, it is also grossed-up by the floor common area. If you consider a floor with a ring corridor (Floor Common Area) that provides access to both Office Areas and mechanical rooms (Building Common Area) you can imagine that if the office portion picked up 100% of the corridor, it would result in a very large gross-up. In this example, under BOMA 1996, both the Office Area and the Building Common Area will split the corridor proportionately. Since the corridor provides access to the mechanical room which serves all tenants in the building, it makes sense that every tenant should pay for a portion of the corridor.

Mark S
March 31, 2012

Thanks. The corridor makes sense to me in that example. But what if the floor has several other spaces such as janitor closets and utility rooms, etc assigned to floor common? Now the building common area (ie mechanical rooms in your example) are getting grossed up by the additional floor common area and a portion is getting paid for by all tenants. There isn't a clear relationship between the utility room and the mechanical room like there is between the corridor and mechanical room. To me at least. It seems like it's being called usable for the sake of the math (gross-up), not because it's actually able to be used differently. Does 2010 make any clearer distinctions? Thanks,

Your Comments ...

Please allow up to 24 hours for your question to appear after it is reviewed.