Oregon climate zones
Oregon’s 36 counties fall in 2 IECC 2021 climate zones: 4C (18), 5B (18).
Zone 4C: mixed-marine
Attic target R60 (ENERGY STAR)Benton County (Marine) · Clackamas County (Marine) · Clatsop County (Marine) · Columbia County (Marine) · Coos County (Marine) · Curry County (Marine) · Douglas County (Marine) · Jackson County (Marine) · Josephine County (Marine) · Lane County (Marine) · Lincoln County (Marine) · Linn County (Marine) · Marion County (Marine) · Multnomah County (Marine) · Polk County (Marine) · Tillamook County (Marine) · Washington County (Marine) · Yamhill County (Marine)
Zone 5B: cool-dry
Attic target R60 (ENERGY STAR)Baker County (Cold) · Crook County (Cold) · Deschutes County (Cold) · Gilliam County (Cold) · Grant County (Cold) · Harney County (Cold) · Hood River County (Cold) · Jefferson County (Cold) · Klamath County (Cold) · Lake County (Cold) · Malheur County (Cold) · Morrow County (Cold) · Sherman County (Cold) · Umatilla County (Cold) · Union County (Cold) · Wallowa County (Cold) · Wasco County (Cold) · Wheeler County (Cold)