DOB updates energy code rule to match 2025 NYC Energy Conservation Code

What happened

The NYC Department of Buildings (DOB) has adopted a final rule that amends its rules on the city's Energy Conservation Code. The notice was published in The City Record on 11/10/2026. It was signed by Buildings Commissioner Ahmed Tigani and dated 10/30/2026. The rule changes section 5000-01 of Chapter 5000 of Title 1 of the Rules of the City of New York (1 RCNY 5000-01).

The rule follows Local Law 47 of 2026. That law was enacted on 12/18/2025 and took effect on 01/01/2026. It updated the NYC Energy Conservation Code to match state energy law and the 2025 updates to the New York State Energy Conservation Construction Code. The new rule brings DOB's rules in line with the 2025 city code. It updates code references from 2020 to 2025 and adds a compliance path called TSPR. It also explains how to document thermal bridge provisions and additional efficiency credits on construction documents, clarifies when progress inspections are "continuous" or "periodic," and makes plain language edits.

Under the rule, applications must follow the Energy Code version in effect when they are filed, through construction and DOB sign-off. Residential projects must follow NYCECC Chapters R2 through R6. Commercial projects must follow either NYCECC Chapters C2 through C6 or 2025 NYC ASHRAE 90.1 in its entirety. On the NYCECC path, windows and other vertical glazing may cover up to 30% of above-grade wall area prescriptively. They may go up to 40% if daylighting controls are added. On the ASHRAE path, the prescriptive limit is 40% of gross wall area. Above that, energy modeling or an envelope trade-off option is required.

The proposed rule was first published on 07/23/2026, and a public hearing was held on 08/27/2026. DOB received 20 comments from two people. DOB declined to extend compliance time as one commenter asked. It made three changes. It fixed a typo that cited Local Law 48 instead of Local Law 47, revised the qualifications for energy modelers, and clarified the requirements for deferred submittals.