855773520-LEED-v5-ID-C-Reference-Guide-Launch-Edition-1 - Page 227

Extracted Content

Climate zones 0–3 Projects in warmer climate zones (0–3) cannot apply any exceptions and must comply entirely with Section 5.5.5. Providing thermal breaks, continuous insulation, and using reflective exterior coatings on exterior surfaces can reduce solar heat gain and prevent moisture intrusion.

Alterations of existing buildings Projects in existing buildings can either show low conductance for the building envelope or improve the conductance of a poorly performing envelope by adding insulation, addressing thermal bridging, or upgrading windows and doors.

Both methods necessitate an analysis comparing the project’s overall envelope conductance to prescriptive requirements for the project’s climate zone in A SHRAE 90.1-2022, Tables 5.5-0 to 5.5-8. Account for all project exterior assemblies including roofs, floors, walls, windows, skylights, and doors. Assess the ASHRAE 90.1-2022 total UA by multiplying the area of each exterior envelope assembly by the U-factor from Tables 5.5-0 to 5.5-8 and summing together all UA values.

Determine the U-value for each project envelope assembly, including adjustments for thermal bridges per ASHRAE 90.1-2022 A10.2 for any thermal bridges that do not meet the requirements in ASHRAE 90.1, Sections 5.5.5. Assess the project’s total UA by multiplying the area of each exterior envelope assembly by the U-factor of the assembly and summing together all UA values.

The project complies if the project total UA is no more than 125% of the ASHRAE 90.1-2022 UA.

If the project total UA is between 125% and 200% of the ASHRAE 90.1-2022 UA, perform additional UA calculations for the envelope before renovations were implemented not more than three years before project registration. Show that the current total project UA is at least 30% lower than the pre-retrofit UA.

PATH 3. INFILTRATION

Either for the whole building or for the compartmentalized space, design or renovate the project’s air barrier to minimize air leakage through the building enclosure. To apply this path for the project only, the project boundary must have exterior exposure including at least one roof, exterior above-grade wall, or exterior floor that is not slab-on-grade. Provide air leakage testing conducted within five years of project occupancy to confirm the project achieves one of the following targeted performance levels.

Initial buildouts or projects in existing buildings:

U.S. Green Building Council LEED v5 Reference Guide for Interior Design and Construction, April 2025 Launch Edition 216