3.5 Building Envelope Data

The user shall provide accurate descriptions for all building envelope assemblies including exterior walls, windows, doors, roofs, exterior floors (including floors above unconditioned spaces), slab-on-grade floors, below grade walls, and below grade floors. The user shall provide data for all of the required descriptors listed in Section 3.5 of this document that correspond with these assemblies. However, the following exception applies:

• Exterior surfaces whose azimuth orientation and tilt differ by no more than 45° and are otherwise the same may be described as a single surface or described using multipliers. This specification would permit a circular form to be described as an octagon.

For unenclosed spaces such as parking garages, crawlspaces and attics, refer to Section 2.4.3 of this manual for modeling requirements.

The user shall provide accurate descriptions for all building envelope assemblies including exterior walls, windows, doors, roofs, exterior floors (including floors above unconditioned spaces), slab-on-grade floors, below grade walls, and below grade floors. The user shall provide data for all of the required descriptors listed in Section 3.5 of this document that correspond with these assemblies. However, the following exception applies:

• Exterior surfaces whose azimuth orientation and tilt differ by no more than 45° and are otherwise the same may be described as a single surface or described using multipliers. This specification would permit a circular form to be described as an octagon.

For unenclosed spaces such as parking garages, crawlspaces and attics, refer to Section 2.4.3 of this manual for modeling requirements.

New buildings are required to comply with Section G1.2.1d which is known as the “Envelope Backstop”. There are two options to comply (1) meet the requirements of Section 5.5, “Prescriptive Building Envelope Compliance Path.” or (2) using Section 5.6, “Building Envelope Trade-Off Compliance Path,” demonstrate that the proposed envelope performance factor does not exceed the base envelope performance factor by more than 15% for multifamily residential, hotel/motel, and dormitory building area types. For all other building area types, the limit is set at 7%. For buildings with both residential and nonresidential occupancies, the limit is established based on the area-weighted average of the gross conditioned floor area. This “Envelope Backstop” requirement only applies to new buildings.