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With the publishing of the 2024 International Energy Conservation Code (IECC), The U.S. Environmental Protection Agency (EPA) has issued new requirements for Energy Star Single-Family New Homes (SFNH) National v3.3 and Multifamily New Construction (MFNC) National v1.3, for states that adopt the 2024 International Energy Conservation Code (IECC), or equivalent.
What’s New in Version 3.3?
The new ENERGY STAR SFNH Version 3.3 has three key differences from Version 3.2:
- A more stringent ENERGY STAR ERI target of ~45-50 for most homes.
- A thermal envelope backstop aligned with the 2024 IECC performance paths:
- In CZ 1-2, ≤ 108% of the total TC per 2024 IECC Table 402.1.2; and
- In CZ 3-8, ≤ 115% of the total TC per 2024 IECC Table 402.1.2.
- An air infiltration backstop of 3.5 ACH50, with alternative metrics for small homes and attached homes, and an allowance of 4 ACH50 for homes permitted before 1/1/2027.
These new versions of the ENERGY STAR program requirements can be used to meet the minimum standards for the 45L tax credit 2025 for new home builders.
While primarily for new construction homes, existing homes undergoing substantial reconstruction or rehabilitation are also eligible to participate in the ENERGY STAR SFNH program.
More than 2.7 million (and counting) U.S. homes and apartments have earned the ENERGY STAR to date. According to EPA, these homes helped reduce CO2 emissions by 4 million metric tons nationwide.