In 2023, New York State amended its laws to require updates to New York State Uniform Fire Prevention and Building Code (Uniform Code) and the State Energy Conservation Construction Code (Energy Code). These updates would “prohibit the installation of fossil-fuel equipment and building systems, in any new building not more than seven stories in height, except for a new commercial or industrial building greater than one hundred thousand square feet in conditioned floor area, on or after December thirty-first, [2025], and … prohibit the installation of fossil-fuel equipment and building systems, in all new buildings after December thirty-first, [2028].”1 This amendment supported New York State’s goal of reducing greenhouse gas (GHG) emissions.
Several unions and trade groups filed a lawsuit challenging the underlying statute, arguing that the federal Energy Policy and Conservation Act (EPCA) preempted the statute.2 While that lawsuit was pending, the State Fire Prevention and Building Code Council (the Council), which is charged with updating and amending the Uniform Code and Energy Code, began the update process in 2024. On July 23, 2025, the federal district court for the Northern District of New York issued a decision and order finding that EPCA did not preempt New York’s law, and notified the plaintiffs that it would enter judgment against them; that judgment became final on Aug. 21, 2025.3 On July 25 and 27, respectively, the Council adopted the changes to the Uniform Code and Energy Code. Those changes became final on Oct. 1, 2025, when the New York State Department of State published the Notices of Adoption for the amended and updated Codes in the State Register. The Notices of Adoption are the final step in the rulemaking process.
The updated Codes become effective on Dec. 31, 2025. During the transition period between Oct. 1, 2025, and Dec. 31, 2025, regulated parties have the option of complying with either the provisions of the 2025 Uniform Code or the 2020 Uniform Code. However, beginning on Dec. 31, 2025, regulated parties submitting building permit applications must comply with the 2025 Uniform Code, the 2025 Energy Code, and NYS ASHRAE 90.1-2025.
EPA Reconsideration of Certain AIM Requirements
On Oct. 3, 2025, the U.S. Environmental Protection Agency (EPA) proposed to loosen existing rules governing the phaseout of hydrofluorocarbons (HFCs), chemicals used in cooling equipment that are potent GHGs. The current rules were issued in 2023 pursuant to the American Innovation and Manufacturing (AIM) Act, a bipartisan compromise enacted in December 2020 and signed by President Trump, which authorized EPA to phase down production and consumption of HFCs, enact sector-based restrictions to facilitate a transition to next-generation technologies, and pass regulations for the purpose of maximizing reclamation and minimizing releases of HFCs. Those 2023 rules prohibited the manufacture and import of products that use HFCs with higher global warming potential (GWP, a measure of the climate impact of a GHG relative to carbon dioxide), prohibited the sale, distribution, and export of those products three years after the manufacturing and import restriction, and prohibited the installation of new refrigeration, air conditioning, and heat pump systems that used higher-GWP HFCs.
EPA’s proposed revisions to its HFC rules came in response to petitions for reconsideration from several industry groups, largely due to supply chain issues and unachievable compliance dates. According to the EPA’s rule summary, the proposal is part of a larger set of deregulatory actions announced in March 2025, and is aimed to “increase flexibility and relax certain restrictions on the use of HFC refrigerants previously established under the Technology Transitions section of the AIM Act.”
Perhaps most relevant in New York, to address concerns about supply chain issues related to R-454B (a lower-GWP HFC used as a refrigerant) the EPA is proposing to remove the installation deadline for systems in residential and light commercial air conditioning and heat pump (AC/HP) systems, where all specified components of such systems were manufactured or imported prior to Jan. 1, 2025. The current installation deadline is Jan. 1, 2026; EPA’s revised regulation would remove the deadline entirely, allowing manufacturers to sell any existing inventory of equipment that uses R-410A, the previously authorized refrigerant. EPA’s revised regulations would also extend existing compliance deadlines and relax limits on the GWP of HFCs used in other types of equipment (generally replacing a GWP limit of 150 or 300 with a GWP limit of 1400 starting in 2026 or 2027, with the GWP limit of 150 or 300 becoming effective on Jan. 1, 2032). In addition to these proposed amendments, EPA is also soliciting comments and additional information that may be used to inform potential government actions relating to supply chain issues for refrigerants.
EPA Public Comment Period and Timeline for HFC Regulatory Changes
The 45-day public comment period will end on Nov. 17, 2025. If a public hearing is requested on or before Oct. 8, 2025, the EPA would hold a virtual public hearing on Oct. 20, 2025. The administration may move quickly to finalize the rule once the public comment period is completed, and may not enforce the current rule’s Jan. 1, 2026 deadlines even if the regulatory revision is not completed by that date.
Compliance Challenges and Variance Requests for New York Building Projects
In New York, the Department of Environmental Conservation (DEC) adopted an amended Part 494 regulation on HFCs in January 2025, which includes prohibitions on new products and equipment that contain HFCs. Those regulations were intended to be consistent with the federal regulations that EPA now seeks to relax and include prohibitions on installation of products and equipment that contain HFCs. The state regulations, however, are independent regulatory requirements that for now remain unaffected by the recently announced federal effort to remove the installation deadline for the residential and light commercial AC/HP subsector. The federal and state regulations have created challenges for developers currently constructing or shortly seeking to begin construction on new or retrofitted buildings that go into service after 2026. Although DEC is currently accepting applications for variance requests for compliance with Part 494 regulations on the grounds of impossibility, economic hardship, and force majeure, it will be interesting to see if any of EPA’s proposed action impacts those determinations, or leads to a similar effort in the state to afford more time for buildings to comply with regulations requiring purchase of new equipment that as yet is not available in the market and may prove to be delayed further given this newly-announced federal effort.
1 Energy Law § 11-104 and Executive Law § 378.
2 Mulhern Gas Co., Inc. et al. v. Mosley, et al. (Case No. 1:23-cv-1267, N.D.N.Y.).
3 Mulhern Gas Co. v. Mosley, __ F. Supp. 3d __, 2025 WL 206194 (N.D.N.Y. July 23, 2025). The plaintiffs have appealed the Court’s decision to the Court of Appeals for the Second Circuit, and are seeking an injunction pending appeal. Mulhern Gas Co., Case No. 1:23-cv-1267, N.D.N.Y,, ECF No. 70. The appeal relies heavily on a 2024 decision by the Ninth Circuit Court of Appeals holding that EPCA preempted an ordinance passed by the City of Berkeley, California that generally prohibited the installation of natural gas pipelines within newly constructed buildings. Cal. Restaurant Assoc. v. City of Berkeley, 89 F.4th 1094 (9th Cir. 2024) (amended opinion on denial of rehearing en banc).