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Extracted Content
Analysis period A 25-year period was selected because it captures a significant enough timeframe for projects to see the impacts of their operational carbon emissions from energy and refrigerants and from regular cycles of renovations, in comparison with initial carbon embodied. It does not extend further, unlike some industry projections. This is because future uncertainties grow increasingly dominant over time (e.g., grid decarbonization and advancements in building technologies).
Operational carbon emissions The EAp1: Operational Carbon Projection and Decarbonization Plan calculates the business as usual (BAU) carbon projection from operational emissions from energy over 25 years. The BAU assumes that emissions from fuel use will remain constant, and that emissions from electricity will decline by 95% over 25 years from the base year. See EAp1: Operational Carbon Projection and Decarbonization Plan for more information.
Refrigerant emissions EAp5: Fundamental Refrigerant Management calculates the annual refrigerant emissions. Use a default annual leakage rate of 2% OR an annual leakage rate of 1% for projects pursuing Option 2: Limit Refrigerant Leakage of EAc7: Enhanced Refrigerant Management.
Embodied carbon emissions MRp2: Quantify and Assess Embodied Carbon calculates the embodied carbon in GWP (kgCO2e) of the structure, enclosure, and hardscape. To calculate the embodied carbon, refer to the assumptions found in MRp2: Quantify and Assess Embodied Carbon .
To find the upfront embodied carbon emissions, multiply the MRp2: Quantify and Assess Embodied Carbon embodied carbon values by 1.5 to account for interiors and MEP products, A4, and A5 emissions. Recurring embodied carbon assumes the project undergoes renovations every 10 years. To account for the recurring embodied carbon, multiply the MRp2: Quantify and Assess Embodied Carbon embodied carbon values by 0.25.
These timeframes are estimates based on common renovation cycles and serve illustrative purposes only.
Transportation emissions Teams may only calculate the emissions projection from transportation when the project pursues LTc4: Transportation Demand Management . The projections assume no change in vehicle miles traveled (VMT) over the 25-year period, and a linear 95% decarbonization of the grid.
U.S. Green Building Council LEED v5 Reference Guide for Building Design and Construction, April 2025 Launch Edition 33