855773644-LEED-v5-BD-C-Reference-Guide-Launch-Edition - Page 223
Extracted Content
Table 1. Key changes in ASHRAE 90.1-2022
| Section | Key change |
|---|---|
| Additional efficiency requirements Section 11 | For the prescriptive method of compliance, designers select from a list of 33 energy efficiency measures to satisfy the total required Energy Credits for a given building type and climate zone, resulting in an average of 4% to 5% savings. These additional savings are also accounted for when determining the Energy Cost Budget Method requirements and in the Building Performance Factors referenced for the Appendix G Performance Rating Method. |
| On-Site Renewable Energy Section 10.5.1.1 | On-site renewable energy is required for the prescriptive method, averaging over 4% savings. The Energy Cost Budget Method and Appendix G Performance Rating Method factors in this prescriptive renewable contribution in determining compliance, although other efficiency measures can make up the difference for project designs without renewable energy. Exceptions to On-Site Renewable Requirements ASHRAE 90.1, Section 10.5.1.1 exempts buildings with inadequate access to solar energy and small buildings with less than 10,000 sq. ft. (929 sq. m.) of conditioned floor area for the three largest floors. The following additional guidance applies to LEED projects: • Where regulatory limitations restrict maximum rooftop solar capacity, use the lesser of the Section 10.5.1.1 criteria or the maximum capacity or area stipulated by regulatory limitations. • Canadian provinces and U.S. eGRID regions aren’t required to have on-site renewable. It’s also not required in other countries where current annual electric grid emissions average less than 20 grams/kWh CO2eq. • ASHRAE 90.1-2022, Addendum K provides additional alternatives for projects to find off-site renewable energy meeting the prescriptive requirements in lieu of the on-site renewable power. |
| Thermal Bridges Section 5.5.5 | A new prescriptive section addresses thermal bridging in the building envelope. For projects utilizing Section 5.6, Building Envelope Trade-off Compliance Path, the Energy Cost Budget Method, or the Appendix G, Performance Rating Method, the proposed design model must account for thermal bridges that don’t meet prescriptive requirements. |
ASHRAE 90.1 Mandatory Provisions
All projects must meet applicable mandatory provisions from the referenced version of ASHRAE 90.1, found in Sections 5.4 (Building Envelope), 6.4 (HVAC), 7.4 (Service Water Heating), 8.4 (Power), 9.4 (Lighting), and 10.4 (Other Equipment).
U.S. Green Building Council LEED v5 Reference Guide for Building Design and Construction, April 2025 Launch Edition 213