Climate zones by state

New York Climate Zones by County

New York's 62 counties span climate zones 4A to 6A under the 2021 International Energy Conservation Code (IECC). Zone 5A is the most common, with 36 of the 62. For reference, New York City is in zone 4A and Albany and Buffalo are in 5A.

Insulation minimums for each zone in New York

ZoneCountiesAtticWood-frame wallsFloors over unheated spaceBasement walls
4A8R-60R-30, or 20+5ci, or 13+10ci, or R-20ciR-19R-10ci or R-13
5A36R-60R-30, or 20+5ci, or 13+10ci, or R-20ciR-30R-15ci, or R-19, or 13+5ci
6A18R-60R-30, or 20+5ci, or 13+10ci, or R-20ciR-30R-15ci, or R-19, or 13+5ci

Minimums from the 2021 IECC (Table R402.1.3). Many areas still enforce an older edition, so check with your local building department. See sources.

Which energy code New York uses

New York enforces the 2024 IECC with amendments for homes (in effect since Dec 2025). Source: US Department of Energy, September 2026. Local governments can adopt newer codes or amendments. See every state's energy code.

What changed from the 2018 map

Eight counties moved one zone warmer in the 2021 map: Allegany County (6 → 5), Broome County (6 → 5), Cattaraugus County (6 → 5), Schoharie County (6 → 5), Schuyler County (6 → 5), Steuben County (6 → 5), Tompkins County (6 → 5), Wyoming County (6 → 5). If your town still enforces the 2018 or 2015 code, the older zone applies to permits.

Every county in New York

NameZone (2021)Zone (2018)Details
Albany County5A5AInsulation →
Allegany County5A6A changedInsulation →
Bronx County4A4AInsulation →
Broome County5A6A changedInsulation →
Cattaraugus County5A6A changedInsulation →
Cayuga County5A5AInsulation →
Chautauqua County5A5AInsulation →
Chemung County5A5AInsulation →
Chenango County6A6AInsulation →
Clinton County6A6AInsulation →
Columbia County5A5AInsulation →
Cortland County5A5AInsulation →
Delaware County6A6AInsulation →
Dutchess County5A5AInsulation →
Erie County5A5AInsulation →
Essex County6A6AInsulation →
Franklin County6A6AInsulation →
Fulton County6A6AInsulation →
Genesee County5A5AInsulation →
Greene County5A5AInsulation →
Hamilton County6A6AInsulation →
Herkimer County6A6AInsulation →
Jefferson County6A6AInsulation →
Kings County4A4AInsulation →
Lewis County6A6AInsulation →
Livingston County5A5AInsulation →
Madison County6A6AInsulation →
Monroe County5A5AInsulation →
Montgomery County6A6AInsulation →
Nassau County4A4AInsulation →
New York County4A4AInsulation →
Niagara County5A5AInsulation →
Oneida County6A6AInsulation →
Onondaga County5A5AInsulation →
Ontario County5A5AInsulation →
Orange County5A5AInsulation →
Orleans County5A5AInsulation →
Oswego County5A5AInsulation →
Otsego County6A6AInsulation →
Putnam County5A5AInsulation →
Queens County4A4AInsulation →
Rensselaer County5A5AInsulation →
Richmond County4A4AInsulation →
Rockland County5A5AInsulation →
Saratoga County5A5AInsulation →
Schenectady County5A5AInsulation →
Schoharie County5A6A changedInsulation →
Schuyler County5A6A changedInsulation →
Seneca County5A5AInsulation →
St. Lawrence County6A6AInsulation →
Steuben County5A6A changedInsulation →
Suffolk County4A4AInsulation →
Sullivan County6A6AInsulation →
Tioga County5A5AInsulation →
Tompkins County5A6A changedInsulation →
Ulster County6A6AInsulation →
Warren County6A6AInsulation →
Washington County5A5AInsulation →
Wayne County5A5AInsulation →
Westchester County4A4AInsulation →
Wyoming County5A6A changedInsulation →
Yates County5A5AInsulation →

Source: Pacific Northwest National Laboratory, Guide to Determining Climate Zone by County: Building America and IECC 2021 Updates (2022).

Frequently asked questions

What climate zone is New York?

New York spans IECC climate zones 4A to 6A; zone 5A is the most common. Find your county in the table above, or search by ZIP code.

How much attic insulation do I need in New York?

The 2021 IECC calls for R-60 in the attic everywhere in New York.

What energy code does New York use?

New York enforces the 2024 IECC with amendments for homes (in effect since Dec 2025). Source: US Department of Energy, September 2026. Local governments can adopt newer codes or amendments.

More for New York: Last frost dates in New York · New York planting zones · Frost line depth by state