Gross Floor Area: Areas to exclude

Hi, Carlos. Please be advised that PIf2 and GFA calculations differ from IEQp1 and ASHRAE 62.1 areas. Fortunately, USGBC has provideded a spreasheet with guidance on how to account for different space types. The Environmental Quality Space Type Matrix can be found at https://www.usgbc.org/resources/environmental-quality-space-type-matrix

Replying to your questions:

a) Emergency stairs: must be included in PIf2, but are excluded from IEQp1, IEQc1, IEQc3.2 (Option 2, only) and many more. Please refer to the stated document for more exclusiones.

b) HVAC / MEP rooms: same as above.

c) Storage: must be included in PIf2. Please be advised that these spaces are accounted for (or excluded from) other credits, depending on its use: food storage, inactive / unoccupied storage, OR active storage. Again, the Space Matrix provide guidance for each.

Inactive spaces are nonoccupied (defined as spaces designed for equipment and machinery or storage with no human occupancy except for maintenance, repairs, and equipment retrieval). For areas with equipment retrieval, the space is only nonoccupied if the retrieval is occasional. 

You should also check on ASHRAE 90.1 gross floor area definition: "the sum of the floor areas of the spaces within the building, including basements, mezzanine and intermediate-floored tiers, and penthouses with a headroom height of 7.5 ft (2.3 m) or greater. It is measured from the exterior faces of exterior walls or from the centerline of walls separating buildings, but excluding covered walkways, open roofed-over areas, porches and similar spaces, pipe trenches, exterior terraces or steps, chimneys, roof overhangs, and similar features."

I hope this helps. Good luck!

Carlos: I concur with Andres. LEED defines Gross Floor Area as follows: "Generally, the gross floor area is the sum of the floor areas of the spaces within the building, including basements, mezzanine and intermediate-floored tiers, and penthouses with headroom height of 7.5 ft (2.2 meters) or greater. Measurements must be taken from the exterior faces of exterior walls OR from the centerline of walls separating buildings, OR (for LEED ID+C projects ) from the centerline of walls separating spaces. Excludes non-enclosed (or non-enclosable) roofed-over areas, such as exterior covered walkways, porches, terraces or steps, roof overhangs, and similar features. Excludes air shafts, pipe trenches, chimneys and floor area dedicated to the parking and circulation of motor vehicles."

Hello! I have a question on this topic. In my project I have two basement floors, containing parking and machine rooms, changing rooms, etc. To calculate the Gross Floor Area of the project, should I discount the parking area only? Or not?

Thanks!!!

Reference the LEED MPR Supplemental Guidance for LEED v2009 projects. Specifically the section on "How to treat parking garages" states that "Parking garages may not be included in the gross floor area of the LEED project building."

I have a question in relation to this. Would an unconditioned mechanical room at on the roof of the building need to be counted in the Gross Area?