Climate ZonesMinnesotaMille Lacs County

What Climate Zone is Mille Lacs County, MN?

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

IECC Climate Zone
6A
Winter 99% Design
-13°F
Summer 1% Design
88°F
ZIP Codes
8
Cities
1

Mille Lacs County, Minnesota is classified under IECC Climate Zone 6A (Cold - Humid), a heating-dominated region with humid moisture conditions. With 8 ZIP codes and 1 communities, every HVAC installation in Mille Lacs County must use the ASHRAE design temperatures of -13°F (99% winter heating) and 88°F (1% summer cooling) for accurate Manual J load calculations.

As a heating-dominated zone, Mille Lacs 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 -13°F design conditions.

Mille Lacs County Insulation Requirements (IECC 2021)

Minimum insulation R-values and window performance for Climate Zone 6A in Mille Lacs County, MN.

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

Mille Lacs County HVAC Contractors: Get Your Free Manual J Report

Climate Zone 6A requires precise load calculations. Upload your Mille Lacs County blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with Mille Lacs County's exact design temperatures (-13°F winter / 88°F summer).

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Verify Your Mille Lacs County ZIP Code

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

Mille Lacs County covers 8 ZIP codes including: 55371, 56313, 56330, 56342, 56353, 56359, 56363, 56386

Mille Lacs County Design Temperatures

Official ASHRAE design temperatures for Mille Lacs County, MN, used for accurate Manual J load calculations.

Winter 99% Design Temp
-13°F
Heating load calculation baseline
Summer 1% Design Temp
88°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 Mille Lacs 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 Mille Lacs County, MN

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

Recommended HVAC Equipment for Mille Lacs 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 Minnesota

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

Get Free Manual J Calculations for Mille Lacs County

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Mille Lacs County design temps
Zone 6A compliant
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