Elevator Shaft and Stairwell included in gsf for Occupancy?

Charles Nepps

NH Green Consulting

LEEDuser Premium Member

80 thumbs up

September 24, 2016

I'm working on a 28 floor building that is pursuing certification as a core & shell (v2009). As we do not know what the occupancy will actually be, we need to base it on the gsf, per Appendix 1 of the reference guide. This makes perfect sense, since we really have no idea how the final "leasable space" will be built out. The reference guide states the gsf should include "all floor penetrations that connect one floor to another. ...Other spaces such as common areas, mechanical spaces, and circulation should be included in the gross square footage of the building." Our building includes several emergency egress stairwells, required by code, and a bank of six elevators. It seem to me these should be treated as "fixed" areas, as they obviously will not be modified and included in future built out leasable space. Has anyone had experience/success excluding stairwell and elevator shaft area numbers from the gsf calcs for determining occupancy?

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Summer Minchew

Managing Partner

Ecoimpact Consulting

LEEDuser Expert

171 thumbs up

Tue, 09/27/2016 - 14:09

Charles, your logic makes sense however the way that USGBC has structured Default Occupancy Counts in Appendix 1 includes circulation. From the reference guide: "The defaults provided above are based on gross square foot per occupant and not net or leasable square foot per occupant. Gross square footage is defined as the sum of all areas on all floors of a building included within the outside faces of the exterior wall including all floor penetrations that connect one floor to another. This can be determined by taking the building foot print and multiplying it by the number of floors in the building. Projects which contain underground and/or structured parking, may exclude that area from the gross square footage used for the calculation. Other spaces such as common areas, mechanical spaces, and circulation should be included in the gross square footage of the building."

Charles Nepps

NH Green Consulting

LEEDuser Premium Member

80 thumbs up

Tue, 09/27/2016 - 14:59

Thanks Summer. I expected the argument that the the occupancy counts already compensate for the unusable space, was likely to be the Reviewer's comment should we attempt to exclude the stairwells and elevator shafts from the numbers. However given the size of the building and number of shafts and stairwells, it does work out to be a pretty significant number, so I wonder if it doesn't really overstate the potential occupancy.