Climate zones by state

Georgia Climate Zones by County

Georgia's 159 counties span climate zones 2A to 3A under the 2021 International Energy Conservation Code (IECC). Zone 3A is the most common, with 118 of the 159. For reference, Savannah is in zone 2A and Atlanta and Augusta are in 3A.

Insulation minimums for each zone in Georgia

ZoneCountiesAtticWood-frame wallsFloors over unheated spaceBasement walls
2A41R-49R-13, or R-10ciR-13None required
3A118R-49R-20, or 13+5ci, or R-15ciR-19R-5ci or R-13

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 Georgia uses

Georgia enforces the 2015 IECC with amendments for homes (in effect since Jan 2020). 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

28 counties moved one zone warmer in the 2021 map: Banks County (4 → 3), Calhoun County (3 → 2), Catoosa County (4 → 3), Chattooga County (4 → 3), Coffee County (3 → 2), Dade County (4 → 3), Dawson County (4 → 3), Dougherty County (3 → 2), Early County (3 → 2), Fannin County (4 → 3), Floyd County (4 → 3), Franklin County (4 → 3), and 16 more marked in the table below. If your town still enforces the 2018 or 2015 code, the older zone applies to permits.

Every county in Georgia

NameZone (2021)Zone (2018)Details
Appling County2A2AInsulation →
Atkinson County2A2AInsulation →
Bacon County2A2AInsulation →
Baker County2A2AInsulation →
Baldwin County3A3AInsulation →
Banks County3A4A changedInsulation →
Barrow County3A3AInsulation →
Bartow County3A3AInsulation →
Ben Hill County3A3AInsulation →
Berrien County2A2AInsulation →
Bibb County3A3AInsulation →
Bleckley County3A3AInsulation →
Brantley County2A2AInsulation →
Brooks County2A2AInsulation →
Bryan County2A2AInsulation →
Bulloch County3A3AInsulation →
Burke County3A3AInsulation →
Butts County3A3AInsulation →
Calhoun County2A3A changedInsulation →
Camden County2A2AInsulation →
Candler County3A3AInsulation →
Carroll County3A3AInsulation →
Catoosa County3A4A changedInsulation →
Charlton County2A2AInsulation →
Chatham County2A2AInsulation →
Chattahoochee County3A3AInsulation →
Chattooga County3A4A changedInsulation →
Cherokee County3A3AInsulation →
Clarke County3A3AInsulation →
Clay County3A3AInsulation →
Clayton County3A3AInsulation →
Clinch County2A2AInsulation →
Cobb County3A3AInsulation →
Coffee County2A3A changedInsulation →
Colquitt County2A2AInsulation →
Columbia County3A3AInsulation →
Cook County2A2AInsulation →
Coweta County3A3AInsulation →
Crawford County3A3AInsulation →
Crisp County3A3AInsulation →
Dade County3A4A changedInsulation →
Dawson County3A4A changedInsulation →
Decatur County2A2AInsulation →
DeKalb County3A3AInsulation →
Dodge County3A3AInsulation →
Dooly County3A3AInsulation →
Dougherty County2A3A changedInsulation →
Douglas County3A3AInsulation →
Early County2A3A changedInsulation →
Echols County2A2AInsulation →
Effingham County2A2AInsulation →
Elbert County3A3AInsulation →
Emanuel County3A3AInsulation →
Evans County2A2AInsulation →
Fannin County3A4A changedInsulation →
Fayette County3A3AInsulation →
Floyd County3A4A changedInsulation →
Forsyth County3A3AInsulation →
Franklin County3A4A changedInsulation →
Fulton County3A3AInsulation →
Gilmer County3A4A changedInsulation →
Glascock County3A3AInsulation →
Glynn County2A2AInsulation →
Gordon County3A4A changedInsulation →
Grady County2A2AInsulation →
Greene County3A3AInsulation →
Gwinnett County3A3AInsulation →
Habersham County3A4A changedInsulation →
Hall County3A4A changedInsulation →
Hancock County3A3AInsulation →
Haralson County3A3AInsulation →
Harris County3A3AInsulation →
Hart County3A3AInsulation →
Heard County3A3AInsulation →
Henry County3A3AInsulation →
Houston County3A3AInsulation →
Irwin County3A3AInsulation →
Jackson County3A3AInsulation →
Jasper County3A3AInsulation →
Jeff Davis County2A2AInsulation →
Jefferson County3A3AInsulation →
Jenkins County3A3AInsulation →
Johnson County3A3AInsulation →
Jones County3A3AInsulation →
Lamar County3A3AInsulation →
Lanier County2A2AInsulation →
Laurens County3A3AInsulation →
Lee County3A3AInsulation →
Liberty County2A2AInsulation →
Lincoln County3A3AInsulation →
Long County2A2AInsulation →
Lowndes County2A2AInsulation →
Lumpkin County3A4A changedInsulation →
Macon County3A3AInsulation →
Madison County3A3AInsulation →
Marion County3A3AInsulation →
McDuffie County3A3AInsulation →
McIntosh County2A2AInsulation →
Meriwether County3A3AInsulation →
Miller County2A2AInsulation →
Mitchell County2A2AInsulation →
Monroe County3A3AInsulation →
Montgomery County3A3AInsulation →
Morgan County3A3AInsulation →
Murray County3A4A changedInsulation →
Muscogee County3A3AInsulation →
Newton County3A3AInsulation →
Oconee County3A3AInsulation →
Oglethorpe County3A3AInsulation →
Paulding County3A3AInsulation →
Peach County3A3AInsulation →
Pickens County3A4A changedInsulation →
Pierce County2A2AInsulation →
Pike County3A3AInsulation →
Polk County3A3AInsulation →
Pulaski County3A3AInsulation →
Putnam County3A3AInsulation →
Quitman County3A3AInsulation →
Rabun County3A4A changedInsulation →
Randolph County3A3AInsulation →
Richmond County3A3AInsulation →
Rockdale County3A3AInsulation →
Schley County3A3AInsulation →
Screven County3A3AInsulation →
Seminole County2A2AInsulation →
Spalding County3A3AInsulation →
Stephens County3A4A changedInsulation →
Stewart County3A3AInsulation →
Sumter County3A3AInsulation →
Talbot County3A3AInsulation →
Taliaferro County3A3AInsulation →
Tattnall County2A2AInsulation →
Taylor County3A3AInsulation →
Telfair County3A3AInsulation →
Terrell County3A3AInsulation →
Thomas County2A2AInsulation →
Tift County2A3A changedInsulation →
Toombs County2A2AInsulation →
Towns County3A4A changedInsulation →
Treutlen County3A3AInsulation →
Troup County3A3AInsulation →
Turner County3A3AInsulation →
Twiggs County3A3AInsulation →
Union County3A4A changedInsulation →
Upson County3A3AInsulation →
Walker County3A4A changedInsulation →
Walton County3A3AInsulation →
Ware County2A2AInsulation →
Warren County3A3AInsulation →
Washington County3A3AInsulation →
Wayne County2A2AInsulation →
Webster County3A3AInsulation →
Wheeler County3A3AInsulation →
White County3A4A changedInsulation →
Whitfield County3A4A changedInsulation →
Wilcox County3A3AInsulation →
Wilkes County3A3AInsulation →
Wilkinson County3A3AInsulation →
Worth County2A3A changedInsulation →

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 Georgia?

Georgia spans IECC climate zones 2A to 3A; zone 3A is the most common. Find your county in the table above, or search by ZIP code.

How much attic insulation do I need in Georgia?

The 2021 IECC calls for R-49 in the attic everywhere in Georgia.

What energy code does Georgia use?

Georgia enforces the 2015 IECC with amendments for homes (in effect since Jan 2020). Source: US Department of Energy, September 2026. Local governments can adopt newer codes or amendments.

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