What Climate Zone is Dunn County, WI?

Dunn County is in IECC Climate Zone 6A (Cold - Humid). Get accurate Manual J load calculations with official ASHRAE design temperatures for Dunn County.

IECC Climate Zone
6A
Winter 99% Design
-10°F
Summer 1% Design
89°F
ZIP Codes
12
Cities
1

Dunn County, Wisconsin is classified under IECC Climate Zone 6A (Cold - Humid), a heating-dominated region with humid moisture conditions. With 12 ZIP codes and 1 communities, every HVAC installation in Dunn County must use the ASHRAE design temperatures of -10°F (99% winter heating) and 89°F (1% summer cooling) for accurate Manual J load calculations.

As a heating-dominated zone, Dunn County requires robust insulation — a minimum of R-20 in walls, R-49 in ceilings, and R-30 in floors. Windows must meet a U-factor of 0.3 or lower. These requirements ensure homes maintain comfort during the coldest -10°F design conditions.

Dunn County Insulation Requirements (IECC 2021)

Minimum insulation R-values and window performance for Climate Zone 6A in Dunn County, WI.

Building ComponentMinimum RequirementUnit
Ceiling / Attic InsulationR-49R-value
Wall InsulationR-20R-value
Floor InsulationR-30R-value
Window U-Factor0.3BTU/hr-ft²-°F
Window SHGC0.4Coefficient
Air Infiltration0.15ACH50

Dunn County HVAC Contractors: Get Your Free Manual J Report

Climate Zone 6A requires precise load calculations. Upload your Dunn County blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with Dunn County's exact design temperatures (-10°F winter / 89°F summer).

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Verify Your Dunn County ZIP Code

Enter your ZIP code to confirm it's in Dunn County and get climate zone details.

Dunn County covers 12 ZIP codes including: 54725, 54730, 54734, 54735, 54737, 54739, 54749, 54751 and 4 more

Dunn County Design Temperatures

Official ASHRAE design temperatures for Dunn County, WI, used for accurate Manual J load calculations.

Winter 99% Design Temp
-10°F
Heating load calculation baseline
Summer 1% Design Temp
89°F
Cooling load calculation baseline
Summer Wet Bulb
73°F
Latent load (humidity) calculation

IECC Zone 6A Insulation Requirements

Minimum insulation and window requirements for Dunn County per IECC 2021 energy code.

Wall Insulation:R-20
Roof/Ceiling:R-49
Floor Insulation:R-30
Window U-Factor:0.3
Window SHGC:0.4

Climate Zone 6A: Cold - Humid - Cold climate with very cold winters and warm summers. Very high heating loads, moderate cooling needs.

Cities in Dunn County, WI

1 cities and communities in Dunn County share Climate Zone 6A requirements.

Recommended HVAC Equipment for Dunn County

Heating Systems

Gas furnace (96%+ AFUE)
Boiler
Cold climate heat pump
Typical AFUE
96-98%

Cooling Systems

AC (13-15 SEER)
Typical SEER
13-15 SEER

Nearby Counties in Wisconsin

Compare climate zones with other counties in Wisconsin. Different zones require different HVAC equipment sizing.

Get Free Manual J Calculations for Dunn County

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Dunn County design temps
Zone 6A compliant
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