855773520-LEED-v5-ID-C-Reference-Guide-Launch-Edition-1 - Page 240

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Adjusted benchmarks for limiting effective GWP For equipment that has been specifically designed to limit effective refrigerant GWP by minimizing refrigerant charge, projects may reference comparable equipment to establish an adjusted benchmark instead of using the refrigerant charge for the project equipment.

To be eligible to apply adjusted benchmarks, neither the GWP for the comparable equipment nor the GWP for the referenced project equipment may exceed the GWP benchmark in Table 1. Comparable equipment shall have the same equipment type description and size category as the referenced project equipment (see section 6.8 tables in the ASHRAE 90.1 standard for equipment types and size categories).

Calculate the adjusted benchmark by multiplying the original Table 1 benchmark by the ratio of refrigerant charge per unit of capacity for the comparable equipment versus the project equipment.

Example: Adjusted benchmark calculation The project team evaluates two water-cooled centrifugal chiller alternatives with GWP less than 700, the first with a refrigerant charge per unit of capacity equal to 3.0 lb/ton (0.38 kg/kW), the second with a refrigerant charge per unit of capacity equal to 1.5 lb/ton (0.19 kg/kW). The project team selects the second chiller.

From Table 1, the GWP Benchmark for HVAC equipment is 700. The adjusted GWP Benchmark is 1,400, calculated as 700 x 3.0 / 1.5.

Building-level documentation Teams can elect to include the refrigerant impacts from the base building when compliance cannot be demonstrated based solely on new equipment within the project scope. At minimum, include all new and existing refrigerant-containing equipment that supplies heating, cooling, SWH, or process energy to the project.

Option 2. Limit Refrigerant Leakage

Combine design and construction strategies with operational best practices to effectively manage refrigerant leakage for the life of the project.

Compliance must be documented at the building-level for initial buildout of projects with less than 50% of the capacity of refrigerant-using equipment in the project scope and for all other projects that do not have refrigerant-using systems in the project boundary.

U.S. Green Building Council LEED v5 Reference Guide for Interior Design and Construction, April 2025 Launch Edition 229