New Buildings Institute has released new code language that serves as a building decarbonization overlay to the 2021 International Energy Conservation Code (IECC). The Building Decarbonization Code is a groundbreaking tool aiming to deliver carbon neutral performance. It is designed to help states and cities working to mitigate carbon resulting from energy use in the built environment, which accounts for 39 percent of U.S. emissions. It also offers market insight into rules that will determine how new buildings are designed and constructed in the future to curb the worst impacts of climate change.
The recent efficiency gains in the 2021 IECC create ideal timing to offer a “decarbonization overlay” to the model code. The Building Decarbonization Code language is structured to be compatible with the current version of the IECC and covers both residential and commercial construction. The IECC is in use or adopted in 49 states, the District of Columbia, the U.S. Virgin Islands, NYC and Puerto Rico, according to the International Code Council (ICC), which manages the code’s development.
“The Building Decarbonization Code is designed to meet jurisdictions where they are,” says NBI Director of Codes Kim Cheslak, one of the developers. “We recognize that not every state and city is in a position to require all-electric construction in their next code cycle, but many jurisdictions are ready for the electric-ready or electric-preferred options for new construction.”
The Building Decarbonization Code, which is part of a larger toolkit being developed for cities and states, is focused on codes for new construction with the potential of adding code language for existing buildings in a future version. While not an all-electric code, the language does prioritize efficient electric equipment and is designed to be flexible. Sections cover All-Electric and Mixed-Fuel options.
The overlay incorporates code solutions to the inclusion of key electrification technologies, including solar, electric vehicles, battery storage, and demand response and is designed to enhance building-grid integration so the buildings can be effectively used as an asset to shift times when energy is used and alleviate pressure on the electricity grid during peak demand periods.
Technology choices are based on climate zone to ensure that the appropriate heating and cooling technologies are practical for the specific location. For example, electric resistance heating is not prohibited as heat pumps in cold temperature climates may require electric resistant strip heat as a practical back up. Commercial codes consider different building typologies and available technology to provide practical end use electrification. Under current technology limitations, the commercial code may not be able to fully decarbonize all end uses.
Jurisdictions may use either section of the overlay in its entirety or use portions of either or both to amend the 2021 IECC to a code that is right for adoption to meet the needs of their communities and supports their climate goals.
“Many jurisdictions have aggressive climate-related goals, and over 200 cities have made pledges to achieve 100 percent clean energy or ‘net zero’ emissions,” Cheslak adds. “This new code gives them a powerful tool they can use right away.”
To learn more about building decarbonization through codes, watch an NBI on demand webinar, Getting to Zero: Carbon Neutral Codes.