Insulation R-values by climate zone
The U.S. is split into IECC climate zones 1 (hottest) to 8 (coldest). Recommended R-values rise with colder zones. Pick a zone, or enter your ZIP on the calculator to find yours.
ZIP → recommended R-values & material thickness
The U.S. is split into IECC climate zones 1 (hottest) to 8 (coldest). Recommended R-values rise with colder zones. Pick a zone, or enter your ZIP on the calculator to find yours.