Oklahoma climate zones
Oklahoma’s 77 counties fall in 3 IECC 2021 climate zones: 3A (59), 4A (15), 4B (3).
Zone 3A: warm-humid
Attic target R49 (ENERGY STAR)Adair County (Mixed-humid) · Atoka County (Mixed-humid) · Beckham County (Mixed-humid) · Blaine County (Mixed-humid) · Bryan County (Mixed-humid) · Caddo County (Mixed-humid) · Canadian County (Mixed-humid) · Carter County (Mixed-humid) · Cherokee County (Mixed-humid) · Choctaw County (Mixed-humid) · Cleveland County (Mixed-humid) · Coal County (Mixed-humid) · Comanche County (Mixed-humid) · Cotton County (Mixed-humid) · Creek County (Mixed-humid) · Custer County (Mixed-humid) · Dewey County (Mixed-humid) · Garvin County (Mixed-humid) · Grady County (Mixed-humid) · Greer County (Mixed-humid) · Harmon County (Mixed-humid) · Haskell County (Mixed-humid) · Hughes County (Mixed-humid) · Jackson County (Mixed-humid) · Jefferson County (Mixed-humid) · Johnston County (Mixed-humid) · Kingfisher County (Mixed-humid) · Kiowa County (Mixed-humid) · Latimer County (Mixed-humid) · Le Flore County (Mixed-humid) · Lincoln County (Mixed-humid) · Logan County (Mixed-humid) · Love County (Mixed-humid) · Marshall County (Mixed-humid) · Mayes County (Mixed-humid) · McClain County (Mixed-humid) · McCurtain County (Mixed-humid) · McIntosh County (Mixed-humid) · Murray County (Mixed-humid) · Muskogee County (Mixed-humid) · Noble County (Mixed-humid) · Okfuskee County (Mixed-humid) · Oklahoma County (Mixed-humid) · Okmulgee County (Mixed-humid) · Pawnee County (Mixed-humid) · Payne County (Mixed-humid) · Pittsburg County (Mixed-humid) · Pontotoc County (Mixed-humid) · Pottawatomie County (Mixed-humid) · Pushmataha County (Mixed-humid) · Roger Mills County (Mixed-humid) · Rogers County (Mixed-humid) · Seminole County (Mixed-humid) · Sequoyah County (Mixed-humid) · Stephens County (Mixed-humid) · Tillman County (Mixed-humid) · Tulsa County (Mixed-humid) · Wagoner County (Mixed-humid) · Washita County (Mixed-humid)
Zone 4A: mixed-humid
Attic target R60 (ENERGY STAR)Alfalfa County (Mixed-humid) · Craig County (Mixed-humid) · Delaware County (Mixed-humid) · Ellis County (Mixed-humid) · Garfield County (Mixed-humid) · Grant County (Mixed-humid) · Harper County (Mixed-humid) · Kay County (Mixed-humid) · Major County (Mixed-humid) · Nowata County (Mixed-humid) · Osage County (Mixed-humid) · Ottawa County (Mixed-humid) · Washington County (Mixed-humid) · Woods County (Mixed-humid) · Woodward County (Mixed-humid)
Zone 4B: mixed-dry
Attic target R60 (ENERGY STAR)Beaver County (Mixed-dry) · Cimarron County (Mixed-dry) · Texas County (Mixed-dry)