The impact of state level residential building code stringency on energy consumption in the United States

Buildings consume 75% of the electricity and 40% of the total energy used in the United States, accounting for 36% of all U.S. carbon dioxide emissions [8]. Every-three years, the International Energy Conservation Code proposes new residential energy-related building codes, with code stringency varying considerably from state to state. We investigated the relationship between building code adoption and per capita electrical and natural gas consumption between 2015 and 2017 for the 48 contiguous states. While factors such as energy prices, the number of heating and cooling days, and population density explained a large percentage of the variation in per capita electrical and natural gas consumption (71.2% and 73.1% respectively), building code stringency explained an additional 6.5% and 1.6% respectively. We found an estimated 13.0% reduction in per capita electrical consumption with current code adoptions, which is similar to the higher end of reductions found in other studies. While research conducted on California and Florida found decreases in per capita natural gas consumption, our national-level analysis showed a 16.7% increase with current code adoptions, likely due to the increased access to natural gas in many states and the increased use of natural gas for major end-use consumption categories in homes (e.g., heating, cooling, water heating).