New York City on Jan. 17 enacted the NYC Existing Building Code and Energy Conservation Code that together will require mandatory air-leakage testing for all buildings, enhance requirements for backup electric heating and eliminate obstacles to rehabilitating existing buildings.
Adoption of the 2025 New York City Energy Conservation Code, or NYCECC, helps the city align its code to the state, which has adopted the 2025 Energy Conservation Construction Code. The codes are aimed at promoting energy efficiency, reliability and long-term cost savings, ICC said. The NYCECC will also enhance requirements for backup electric heating to support resilience during extreme weather events, mandate air-leak testing for all buildings and place demand response requirements for commercial water heating and lighting to help maximize efficiency and savings.
The NYC Existing Building Code, based on the International Existing Building Code, is intended to give building operators flexible compliance options, the International Code Council said in a release. This code aims to simplify the city’s complex regulatory structure, provide guidance to operators filing alteration applications, eliminate obstacles to rehabilitating buildings and make codes easier to navigate, ICC said. Alteration and maintenance of existing buildings will continue to be regulated by the Administrative Code of the City of New York and 2022 New York City Construction Codes until the EBC becomes effective on July 17, 2027, the NYC Department of Buildings says on its website.
“New York City is making history with the adoptions of the 2025 NYC Energy Conservation Code and the NYC Existing Building Code,” Dottie Mazzarella, vice president of government relations at the International Code Council, said in a statement. “These adoptions will modernize the City’s building regulatory framework and strengthen protection for its residents. It has been an honor to contribute to advancing public safety for the people of this great City.”
NYC DOB is expected to begin enforcing the new NYCECC code on March 30, when updated compliance software is available, according to the Urban Green Council. NYCECC energy filings for new construction, additions and renovations submitted before that date must comply with the 2020 NYC Energy Code, according to a NYC DOB service notice. Owners and operators can verify the status of applications and what requirements need to be met before construction begins by using the city’s building information system search tool, per the DOB.
The NYCECC adopts the statewide baseline set by the new Energy Conservation Construction Code of New York State, or ECCCNYS, which incorporates the 2024 IECC and ASHRAE 90.1-2022, “which are respectively estimated to provide … 9.8 percent commercial site energy savings on a national basis,” UGC said.
“The State Energy Code includes measures that advance energy efficiency with improved building envelope performance — through stronger insulation and air sealing, lower U-factors for windows, and provisions for mitigating thermal bridges — updated testing and inspection procedures, and enhanced lighting efficiencies,” said UGC, a nonprofit focused on decarbonizing buildings in New York City.
Like the state’s energy code, NYCECC limits electric resistance heating systems and applies guardrails on the use of backup electric resistance to supplement heat pump systems, according to UGC. But the NYCECC also includes energy efficiency measures that go beyond the statewide baseline, including commercial requirements for the documentation and inspection of air barrier commissions as part of construction documentation.
“Updates to the NYC Energy Code are designed with smart electrification in mind,” UGC said. “NYC’s code includes further restrictions on the use of electric resistance backup heating systems, capping their capacity at 25% of total design load and permitting their use only when temperatures drop below 17F.” The NYCECC also establishes demand response requirements for commercial water heating and lighting to help maximize efficiency and savings, according to UGC.
The NYC DOB is also expected to begin developing code improvements through the design of performance-based compliance pathways, as required by Local Law 32, passed in 2018. The law requires DOB to propose “predicted energy use targets” that would enable eligible buildings over 25,000 square feet to meet energy codes by designing to a performance target based on their forecasted annual energy use, UGC said.
Owners of many buildings in the city must already meet greenhouse gas emission limits through Local Law 97 and energy thresholds in the All-Electric Buildings Law, passed in July. The law requires most new buildings and commercial buildings over 100,000 square feet in New York to use electric heat and appliances. That law was scheduled to take effect this month, but Gov. Kathy Hochul has paused it temporarily.
“With enforcement scheduled for 2026, owners and design teams should begin evaluating how upcoming filings may be impacted by the new code,” Milrose Consultants said in a blog post. “Understanding submission status, anticipated filing dates, and potential design changes will help avoid delays or rework once enforcement begins.”
