New York's Energy Code, Three Layers Deep: State Minimum, NYStretch, and NYC's Own Rules

1. What the Code Is and Who Enforces It

New York has a genuine statewide minimum energy code - unlike home-rule states covered elsewhere on this site - but it isn't the only code in play, because New York City is legally required to enforce something stricter than the state baseline, and it does. Getting this right means keeping three things straight: the state minimum, New York City's own code, and NYStretch, a voluntary local supplement that sits in between.

The statewide minimum

The U.S. Department of Energy's own state profile for New York lists the Current State Code, for both Commercial and Residential construction, as the 2024 IECC, adopted into New York's own Energy Conservation Construction Code of New York State (ECCCNYS). DOE lists the Adoption Date as July 25, 2025 and the Effective Date as December 31, 2025, with State Amendments marked "Yes" and "Can use COM/REScheck" marked Yes for both commercial and residential.¹ The state's own rulemaking defines "2024 ECCCNYS" as "the publication entitled '2024 Energy Conservation Construction Code of New York State' (publication date: December 2024) published by the International Code Council."²

Who enforces it

New York runs its energy code inside the state's broader Uniform Fire Prevention and Building Code system. Outside New York City, local building departments (city, town, or village) enforce the ECCCNYS directly, with the New York State Department of State's Division of Building Standards and Codes providing statewide oversight, technical support, and variance authority. Inside New York City, the Department of Buildings enforces its own NYCECC instead - by state law, any local government energy code, including NYC's, must be at least as stringent as the ECCCNYS.³

Climate zones

New York spans three IECC climate zones - 4A, 5A, and 6A - running from the milder, mixed-humid conditions of New York City and Long Island (Zone 4A) through the state's central and western regions (Zone 5A) to the colder Adirondack and North Country areas (Zone 6A).⁴ New York City itself falls entirely within Zone 4A.⁵

2. Three Layers: State Minimum, NYStretch, and New York City

This is the part that trips people up on a New York project, so it's worth walking through each layer separately, because they don't all move together and they aren't all mandatory.

Layer 1: the ECCCNYS statewide floor

Every jurisdiction in New York State, including New York City, must enforce something at least as strict as the current ECCCNYS - the 2024-IECC-based edition effective December 31, 2025. This is the floor, not a ceiling; any municipality is free to require more.

Layer 2: NYStretch - voluntary, and not automatic

NYStretch Energy Code-2020 is a model code developed and published by NYSERDA specifically so that municipalities outside New York City could voluntarily adopt something more stringent than the state minimum, without having to write their own amendments from scratch. NYSERDA's own materials describe it directly: NYStretch is "a supplement to the 2020 Energy Conservation Construction Code of New York State (ECCC NYS)," intended "to be about one cycle ahead of the current State Energy Code," and "available for voluntary adoption by local governments as a more stringent local energy code."⁶ As of this research, NYSERDA's NYStretch program materials still describe the current published version as NYStretch-2020, built against the 2020 ECCCNYS baseline⁶ - even though the statewide minimum itself has since moved to the 2024-IECC-based ECCCNYS. That gap matters: NYStretch was never intended to replace the state minimum, only to give individual municipalities a ready-made, more-stringent option to adopt on their own initiative. Whether your specific town, city, or county has adopted NYStretch - and, if so, exactly how that local adoption interacts with the newer statewide 2024 ECCCNYS baseline - is a question only that municipality's own code office can answer. Don't assume NYStretch applies to your project unless your local building department confirms it.

Layer 3: New York City - its own mandatory code

New York City is a different case entirely: it doesn't have the option to skip a stretch code, because state law already requires NYC's own energy code to exceed the ECCCNYS. The NYC Department of Buildings' own page states this plainly: "By State law, all local government Energy Codes, including the NYCECC, must be more stringent than the ECCCNYS."³ The current transition:

• The 2025 NYCECC, based on the 2025 ECCCNYS (itself built on the 2024 IECC) plus NYC's own amendments, was adopted as Local Law 47 of 2026. Enforcement begins March 30, 2026, for completed job applications filed on or after that date.³
• Applications filed on or before March 29, 2026 continue to be reviewed under the 2020 NYCECC - the prior cycle, which itself had been aligned with NYStretch Energy Code-2020 requirements when it was adopted.³

In other words: outside NYC, NYStretch is an opt-in a municipality may or may not have taken. Inside NYC, an even stricter, NYStretch-influenced code posture has effectively been the mandatory floor since 2020, and it's about to step up again as of March 30, 2026.

3. Your Ways to Comply

Whether your project falls under the statewide ECCCNYS, a NYStretch-adopting municipality, or the NYCECC, the same general compliance paths carry forward, consistent with how the IECC's residential chapter is structured nationally:

Which path fits which project:

• Simple, code-minimum spec homes with standard framing - the prescriptive path is fastest through plan review and the cheapest to document.
• 2x4 walls, large window packages, or one weak component - the UA trade-off (REScheck) is usually the cheapest fix.
• Custom homes or designs the prescriptive/UA path can't cleanly capture - simulated performance costs more and takes longer, but it's the only path flexible enough for genuinely non-standard designs.
• Already paying for a HERS rating for a utility rebate, ENERGY STAR, or a tax credit - use the ERI path and let that rating do double duty as code compliance.

REScheck applies statewide, with a dedicated NYC edition. DOE lists New York's "Can use COM/REScheck" status as Yes for both residential and commercial, statewide.¹ Inside New York City specifically, the NYC Department of Buildings' own Energy Conservation Code page confirms that "REScheck, COMcheck, and DOE2-based software can be used to conduct the energy analysis," with REScheck's scope covering low-rise residential buildings - one- and two-family dwellings and low-rise multifamily (three stories or fewer above grade), while COMcheck and full energy modeling cover everything else, including high-rise residential.³ Confirm you're using the correct edition for your jurisdiction - the standard 2024 IECC edition outside NYC, or the New York City state-specific edition inside it - before submitting.

What about Manual J? New York's own Residential Code carries the same mandatory equipment-sizing requirement as the national model code. An ICC NTA Code Outreach Program bulletin specific to New York confirms this directly: the state's energy code and Uniform Code both require that "heating and cooling equipment shall be sized in accordance with ACCA Manual S based on building loads calculated in accordance with ACCA Manual J or other approved heating and cooling calculation methodologies."⁷ That requirement is baked into the residential code itself and applies statewide, independent of which energy-code layer - state minimum, NYStretch, or NYCECC - governs your project's envelope compliance path.

4. New York-Specific Wrinkles

Don't assume "New York" means one code - confirm which of the three layers applies to your address. A project in a NYStretch-adopting upstate municipality, a project in a non-adopting municipality on the plain statewide ECCCNYS, and a project inside New York City are all under materially different requirements, even though all three sit inside the same state.

The permit-application filing date, not the calendar date, decides which NYC code cycle applies. NYC's own Department of Buildings page draws the line at the application, not the construction date: the 2025 NYCECC applies to "completed job applications filed on or after March 30, 2026," while applications "filed on or before March 29, 2026 can continue review under the 2020 NYCECC."³ A project timed near that cutover should confirm which side of the line its actual filing date falls on.

NYStretch's published baseline hasn't caught up to the new statewide minimum. Because NYStretch-2020 is still written as a supplement to the 2020 ECCCNYS, and the statewide floor has since moved to the 2024-IECC-based ECCCNYS, a municipality that adopted NYStretch some years ago may need to clarify how that local law interacts with the newer state minimum. This is exactly the kind of detail that only your specific municipality's code office can resolve - don't assume either document automatically supersedes the other.

REScheck's scope inside NYC splits by building type, not just by code cycle. Even within New York City, REScheck only covers the low-rise residential side of the NYCECC (generally one- and two-family homes and low-rise multifamily, three stories or fewer above grade); taller residential buildings fall under the commercial-style COMcheck or full energy-modeling path instead.³ Confirm your building's occupancy classification before assuming a REScheck report is the right document for an NYC multifamily project.

Additions, alterations, and renovations trigger the code too - not just new construction. New York's energy code framework, like the NYCECC specifically, reaches window replacements, HVAC upgrades, and insulation work on existing buildings, generally requiring the specific area being altered to meet current standards without necessarily requiring the whole building to be brought up to code.³ Confirm with your local building department exactly which scope of work on an existing home triggers energy-code review.

What to ask your local building department before you finalize a compliance strategy:

1. Is my project inside New York City, or under the jurisdiction of a local building department elsewhere in the state?
2. Outside NYC: has this specific municipality adopted NYStretch, and if so, how does that interact with the current statewide 2024-IECC-based ECCCNYS?
3. Inside NYC: will my permit application be filed before or after March 30, 2026, and therefore under the 2020 NYCECC or the 2025 NYCECC?
4. Does my building's occupancy and story count place it under REScheck's low-rise residential scope, or under COMcheck/full energy modeling instead?
5. Do you require a Manual J load calculation to be submitted with the permit, or only upon request?

5. Frequently Asked Questions

What energy code edition does New York State use? The statewide minimum is the 2024 IECC, adopted into New York's own ECCCNYS, effective December 31, 2025 (adopted July 25, 2025).¹ DOE confirms "Can use COM/REScheck" as Yes statewide. New York City enforces its own separate, stricter code on top of this floor.

Does New York City use the same code as the rest of the state? No. NYC's own NYCECC must, by state law, be at least as stringent as the statewide ECCCNYS.³ The 2025 NYCECC (based on the 2024 IECC plus NYC amendments) was adopted as Local Law 47 of 2026 and begins enforcement March 30, 2026; earlier applications stay under the 2020 NYCECC.

What is NYStretch, and does it apply to my project? NYStretch Energy Code-2020 is a voluntary, more-stringent model code that individual municipalities outside NYC can choose to adopt on top of the state minimum. It is not automatic statewide - only municipalities that have separately adopted it are held to it, and its published baseline is still the 2020 ECCCNYS.⁶ Confirm with your specific municipality.

Is a Manual J load calculation required in New York? Yes. New York's Residential Code carries the same requirement as the national model code: equipment sized per ACCA Manual S based on ACCA Manual J loads or another approved method, statewide.⁷

Who prepares these reports? Travis Smith, The Plans Examiner. He holds the same certification your building department's plan reviewer holds; the specifics are at the end of this page.

6. Get It Right the First Time - Before Plan Review Sends It Back

Need a REScheck report matched to your specific New York jurisdiction? The most common way a New York REScheck submittal gets kicked back is a mismatch between the edition used and the layer that actually governs your project - the plain statewide 2024 IECC edition, a NYStretch-adopting municipality's requirements, or New York City's own state-specific edition. We confirm your jurisdiction and code layer before running the report. A REScheck report is $149, delivered ready to attach to your permit application.

Need a Manual J load calculation? New York's Residential Code ties equipment sizing directly to a documented Manual J, statewide, independent of which energy-code layer applies to your envelope compliance. A room-by-room Manual J report is $249 for homes up to 3,000 sq ft, $349 for 3,001 to 4,500 sq ft, and $449 for 4,501 to 6,000 sq ft.

Need both? The combined Manual J + REScheck package is $349 for homes up to 3,000 sq ft - one submission covering both the equipment-sizing requirement under the residential code and the envelope-compliance requirement under whichever layer of New York's energy code applies to your project.

Every report comes with the same guarantee: accepted by your building department, or we revise it free until it clears.

Contact us with your plans and the city, town, or borough where you're pulling the permit, and we'll confirm which of New York's three code layers applies and which REScheck edition to run - not a generic "New York" answer.

Verification Appendix

Every claim on this page was checked directly against the state's or city's own published code text, rulemaking documents, or agency pages during this research pass - not a national aggregator or a secondary blog summary, except where explicitly noted below.

1. Statewide minimum = 2024 IECC (ECCCNYS), adopted 07/25/2025, effective 12/31/2025, "Can use COM/REScheck" = Yes for both Commercial and Residential. VERIFIED (primary source). energycodes.gov/status/states/new-york's own State Profile table states this directly.¹

2. "2024 ECCCNYS" defined as the "2024 Energy Conservation Construction Code of New York State," publication date December 2024, ICC publication. VERIFIED (primary source). New York State Department of State rule text, dos.ny.gov/system/files/documents/2025/02/2024-12-2-rule-text-energy-code.pdf, Section 1240.2 Definitions.²

3. By state law, all local government Energy Codes (including NYCECC) must be more stringent than the ECCCNYS. VERIFIED (primary source), re-fetched directly for this page. nyc.gov/site/buildings/codes/energy-conservation-code.page states this directly in its own words.³

4. 2025 NYCECC adopted as Local Law 47 of 2026 (based on 2025 ECCCNYS / 2024 IECC and 2025 NYS ASHRAE 90.1); enforcement begins March 30, 2026 for applications filed on or after that date; applications filed on or before March 29, 2026 continue under the 2020 NYCECC. VERIFIED (primary source), re-fetched directly for this page. nyc.gov/site/buildings/codes/energy-conservation-code.page states this directly, including the exact application-date cutover language.³³³

5. REScheck, COMcheck, and DOE2-based software usable for the NYCECC energy analysis; REScheck's practical scope covers low-rise residential (one- and two-family and low-rise multifamily, three stories or fewer), while taller/other buildings use COMcheck or full energy modeling. VERIFIED, primary + corroborating secondary. The software-usability statement is directly from nyc.gov/site/buildings/codes/energy-conservation-code.page.³ The specific building-type/story-count scope split between REScheck and COMcheck under the NYCECC was corroborated via a secondary source (LegalClarity's NYCECC summary, citing UpCodes' own NYCECC 2025 Chapter 1 Administration text and the NYC DOB REScheck/COMcheck program pages) rather than independently re-pulled from the NYCECC chapter text itself during this pass.³

6. NYStretch Energy Code-2020: voluntary, local-adoption-only, written as a supplement to the 2020 ECCCNYS, intended to run about one code cycle ahead of the state minimum in force at publication. VERIFIED (primary source). NYSERDA's own "NYStretch Energy Code-2020: For Elected Officials" fact sheet and the NYStretch program overview page both state this directly, including the phrase "available for voluntary adoption by local governments as a more stringent local energy code."⁶⁶

7. New York's Residential Code / Uniform Code carries an equipment-sizing mandate requiring ACCA Manual S sizing based on ACCA Manual J loads (or another approved method). VERIFIED (primary source, New York-specific). ICC NTA's own "New York requirements for sizing heating ventilation and air conditioning (HVAC) systems" Code Outreach Program bulletin quotes this requirement directly as applying under New York's state energy code and Uniform Code framework.⁷

8. Climate zones 4A, 5A, 6A for New York; New York City entirely within Zone 4A. VERIFIED (DOE/IECC designation), consistent with the national climate-zone framework used and cited elsewhere on this site's state pages, corroborated for NYC specifically by DOE's own climate-region guide as cited in secondary NYCECC summary material.⁴

What remains genuinely unconfirmed: the exact list of New York municipalities that have adopted NYStretch, and precisely how each one has reconciled that local adoption with the newer statewide 2024-IECC-based ECCCNYS baseline; the full text of NYC's 2025 NYCECC amendments beyond the summary points cited above; and whether any specific upstate or Long Island municipality has adopted amendments stricter than the plain statewide minimum outside the NYStretch framework. Confirm any of these directly with the relevant building department before finalizing a compliance strategy.

Sources

This page summarizes New York's statewide energy code, the voluntary NYStretch supplement, and New York City's own separate code for general guidance. Requirements for any specific municipality not named here may differ, particularly regarding NYStretch adoption. Always confirm current requirements with your local building department before finalizing design or bidding.