Tennessee climate zones
Tennessee’s 95 counties fall in 2 IECC 2021 climate zones: 3A (34), 4A (61).
Zone 3A: warm-humid
Attic target R49 (ENERGY STAR)Bedford County (Mixed-humid) · Chester County (Mixed-humid) · Coffee County (Mixed-humid) · Crockett County (Mixed-humid) · Davidson County (Mixed-humid) · Decatur County (Mixed-humid) · Dyer County (Mixed-humid) · Fayette County (Mixed-humid) · Franklin County (Mixed-humid) · Gibson County (Mixed-humid) · Giles County (Mixed-humid) · Grundy County (Mixed-humid) · Hamilton County (Mixed-humid) · Hardeman County (Mixed-humid) · Hardin County (Mixed-humid) · Haywood County (Mixed-humid) · Henderson County (Mixed-humid) · Hickman County (Mixed-humid) · Lauderdale County (Mixed-humid) · Lawrence County (Mixed-humid) · Lewis County (Mixed-humid) · Lincoln County (Mixed-humid) · Madison County (Mixed-humid) · Marion County (Mixed-humid) · Marshall County (Mixed-humid) · Maury County (Mixed-humid) · McNairy County (Mixed-humid) · Moore County (Mixed-humid) · Perry County (Mixed-humid) · Rutherford County (Mixed-humid) · Shelby County (Mixed-humid) · Tipton County (Mixed-humid) · Wayne County (Mixed-humid) · Williamson County (Mixed-humid)
Zone 4A: mixed-humid
Attic target R60 (ENERGY STAR)Anderson County (Mixed-humid) · Benton County (Mixed-humid) · Bledsoe County (Mixed-humid) · Blount County (Mixed-humid) · Bradley County (Mixed-humid) · Campbell County (Mixed-humid) · Cannon County (Mixed-humid) · Carroll County (Mixed-humid) · Carter County (Mixed-humid) · Cheatham County (Mixed-humid) · Claiborne County (Mixed-humid) · Clay County (Mixed-humid) · Cocke County (Mixed-humid) · Cumberland County (Mixed-humid) · DeKalb County (Mixed-humid) · Dickson County (Mixed-humid) · Fentress County (Mixed-humid) · Grainger County (Mixed-humid) · Greene County (Mixed-humid) · Hamblen County (Mixed-humid) · Hancock County (Mixed-humid) · Hawkins County (Mixed-humid) · Henry County (Mixed-humid) · Houston County (Mixed-humid) · Humphreys County (Mixed-humid) · Jackson County (Mixed-humid) · Jefferson County (Mixed-humid) · Johnson County (Mixed-humid) · Knox County (Mixed-humid) · Lake County (Mixed-humid) · Loudon County (Mixed-humid) · Macon County (Mixed-humid) · McMinn County (Mixed-humid) · Meigs County (Mixed-humid) · Monroe County (Mixed-humid) · Montgomery County (Mixed-humid) · Morgan County (Mixed-humid) · Obion County (Mixed-humid) · Overton County (Mixed-humid) · Pickett County (Mixed-humid) · Polk County (Mixed-humid) · Putnam County (Mixed-humid) · Rhea County (Mixed-humid) · Roane County (Mixed-humid) · Robertson County (Mixed-humid) · Scott County (Mixed-humid) · Sequatchie County (Mixed-humid) · Sevier County (Mixed-humid) · Smith County (Mixed-humid) · Stewart County (Mixed-humid) · Sullivan County (Mixed-humid) · Sumner County (Mixed-humid) · Trousdale County (Mixed-humid) · Unicoi County (Mixed-humid) · Union County (Mixed-humid) · Van Buren County (Mixed-humid) · Warren County (Mixed-humid) · Washington County (Mixed-humid) · Weakley County (Mixed-humid) · White County (Mixed-humid) · Wilson County (Mixed-humid)