Energy Efficiency Comparison: California’s 2016 Building Energy Efficiency Standards and International Energy Conservation Code 2015 [2017]

The federal Energy Policy Act of 1992 requires each state to certify that it has reviewed and considered adopting the national model energy standard. Every state must determine if its energy code meets or exceeds the current federal reference code and certify to the Secretary of the U.S. Department of Energy its determination. The federal reference energy code for residential buildings is the International Energy Conservation Code (IECC). States must reevaluate the efficiency requirements of their code against those of the new federal building efficiency reference codes. This report documents the California Energy Commission’s response to this federal law by comparing the energy savings effects between California’s2016 Building Energy Efficiency Standards Title 24, Part 6, to the residential energy requirements of the 2015 International Energy Conservation Code. This report concludes that California’s Building Energy Efficiency Standards exceed the energy savings expected from the residential Chapter 4 of the 2015 International Energy Conservation Code. While significant improvements have been made to the energy stringency levels of the national reference energy codes, California’s residential energy standards contain building measures and building performance operation impacts that are more rigorous, resulting in higher efficiency levels for new residential construction than expected to occur from efficiency requirements of the federal reference energy codes.

View the Energy Conservation Code Comparison.