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?