ANSI/BOMA Z65.1/2010

Malwina, I don't understand your question—possibly because I'm not famliar with that standard. What is the "norm"?

Don't use "rentable" (floor) areas calculated by BOMA/ANSI Z65.1 for PI Form 3. The LEED Form is setup to use floor areas as determined by ASHRAE Standard 62.1. The reasons not to use it are explained further below in my description of the differences between Z65.1 and LEED credit area calculations. I should note, that although Z65.1 is not required for PI Form 3, you will run into Z65.1, oddly enough in the LEED for Healhcare standard under the Site credit 9.1, Areas of Respite. Why a rentable area calculation method is a requirement for a whole building rating system is a mystery to me. It is an unnecessary complication. The Site calculations should be based on standard architecturally calculated GSF (Gross Floor Area). Okay, this is what I know about Z65.1. ANSI/BOMA Z65.1-2010 is an updated version of a standardized method used by owners to calculate rentable (lease) space areas in a building. The problem with using Z65.1 is that the areas calculated would not match up with the way areas are calculated in the LEED credits. EAc1 uses total conditioned floor area, including entire walls. EQp1 & EQc8 use net interior area. Z65.1 splits interior walls among leased spaces, and can split an exterior wall if glazing is dominate -->50%-- on a wall. In other words, Z65.1 calculates areas that fall in-between what the LEED credits use. ANSI/BOMA Z65.1-1996 is the area measurement method most architects are likely familiar with. ANSI/BOMA Z65.1-2010 includes the "legacy" measurement method used in the 1996 version as Method A. It also adds a new measurement option called Method B.