SSc7.2: Exclusions for calculations

Question: What is included and excluded from roof calculations for SSc7.2, Heat Island Effect, Roof?

Short Answer:
    Excluded:
       - equipment
       - solar energy panels
       - appurtenances
       - parapets
       - skylights
       - parking below grade
       - upper deck of parking garage building
       - podium deck – unconditioned spaces

    Included:
       - podium deck – conditioned spaces*
       - roof canopy
       - terraces

* “the deck could be considered as a roof” (see below for more detailed information).



Long Answer:
The following is a list based on information found in the CIRs that can be applied to LEED rating systems before LEED 2009 and in a lesser degree to rating systems LEED 2009 and beyond.
Exclusions: The following areas may be deducted from the calculations.

- equipment (1)
- solar energy panels (1)
- appurtenances (1)
- parapets (2)
- skylights (2)

Parking Below Grade:
The portion of parking garage not under a building is considered non-roof area. It cannot be counted in the calculations for SSc7.2. The vegetated area can be counted towards open space for SSc5.2. (3)

Parking Structure:
“The upper deck of a parking garage is considered a non-roof impervious surface” for a project with a parking structure adjacent to the office building. (4)

Podium Roof:
The podium deck, which covers on-grade parking, cannot be considered a roof area for purposes of this credit. The top deck of an above-grade parking structure is considered non-roof impervious area. If the podium deck covered conditioned space, then the deck could be considered as a roof (for portions not being used for parking). (5)

Roof Canopy:
A free-standing roof canopy which stands over mechanical equipment, connected to the building envelope only at column bases is “effectively part of the roofing systems as it relates to reflectivity and should be included in calculations for this credit.”(6)

Terraces:
If the terrace space acts as a roof, then the area must be included in SSc7.2 calculations.(7)

Neighboring Buildings:
Neighboring buildings that shade the site cannot be counted. “There is no way to ensure that the surrounding and shading buildings will remain in place for the life of the roofing product that is installed.”(8)


(1)  LEED-CS Version 2.0 Reference Guide, pg.107
(2)  LEED-NC v2.1 SSc7.2 CIR Ruling 6/7/2004
(3)  LEED-NC v2.1 SSc7.2 CIR Ruling 5/10/2005
(4)  LEED-NC v2.1 SSc7.2 CIR Ruling 9/24/2001
(5)  LEED-NC v2.2 SSc7.2 CIR Ruling 9/5/2008
(6)  LEED-NC v2.1 SSc7.2 CIR Ruling 9/20/2004
(7)  LEED-NC v2.1 SSc7.2 CIR Ruling 3/11/2003
(8) LEED-NC v2.1 SSc7.2 CIR Ruling 5/24/2004