Wisconsin climate zones
Wisconsin’s 72 counties fall in 2 IECC 2021 climate zones: 5A (30), 6A (42).
Zone 5A: cool-humid
Attic target R60 (ENERGY STAR)Adams County (Cold) · Calumet County (Cold) · Columbia County (Cold) · Crawford County (Cold) · Dane County (Cold) · Dodge County (Cold) · Fond du Lac County (Cold) · Grant County (Cold) · Green County (Cold) · Green Lake County (Cold) · Iowa County (Cold) · Jefferson County (Cold) · Juneau County (Cold) · Kenosha County (Cold) · La Crosse County (Cold) · Lafayette County (Cold) · Milwaukee County (Cold) · Monroe County (Cold) · Outagamie County (Cold) · Ozaukee County (Cold) · Racine County (Cold) · Richland County (Cold) · Rock County (Cold) · Sauk County (Cold) · Vernon County (Cold) · Walworth County (Cold) · Washington County (Cold) · Waukesha County (Cold) · Waushara County (Cold) · Winnebago County (Cold)
Zone 6A: cold-humid
Attic target R60 (ENERGY STAR)Ashland County (Cold) · Barron County (Cold) · Bayfield County (Cold) · Brown County (Cold) · Buffalo County (Cold) · Burnett County (Cold) · Chippewa County (Cold) · Clark County (Cold) · Door County (Cold) · Douglas County (Cold) · Dunn County (Cold) · Eau Claire County (Cold) · Florence County (Cold) · Forest County (Cold) · Iron County (Cold) · Jackson County (Cold) · Kewaunee County (Cold) · Langlade County (Cold) · Lincoln County (Cold) · Manitowoc County (Cold) · Marathon County (Cold) · Marinette County (Cold) · Marquette County (Cold) · Menominee County (Cold) · Oconto County (Cold) · Oneida County (Cold) · Pepin County (Cold) · Pierce County (Cold) · Polk County (Cold) · Portage County (Cold) · Price County (Cold) · Rusk County (Cold) · Sawyer County (Cold) · Shawano County (Cold) · Sheboygan County (Cold) · St. Croix County (Cold) · Taylor County (Cold) · Trempealeau County (Cold) · Vilas County (Cold) · Washburn County (Cold) · Waupaca County (Cold) · Wood County (Cold)