Climate ZonesMaineSomerset County

What Climate Zone is Somerset County, ME?

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

IECC Climate Zone
6A
Winter 99% Design
-9°F
Summer 1% Design
81°F
ZIP Codes
26
Cities
1

Somerset County, Maine is classified under IECC Climate Zone 6A (Cold - Humid), a heating-dominated region with humid moisture conditions. With 26 ZIP codes and 1 communities, every HVAC installation in Somerset County must use the ASHRAE design temperatures of -9°F (99% winter heating) and 81°F (1% summer cooling) for accurate Manual J load calculations.

As a heating-dominated zone, Somerset 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 -9°F design conditions.

Somerset County Insulation Requirements (IECC 2021)

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

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

Somerset County HVAC Contractors: Get Your Free Manual J Report

Climate Zone 6A requires precise load calculations. Upload your Somerset County blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with Somerset County's exact design temperatures (-9°F winter / 81°F summer).

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Verify Your Somerset County ZIP Code

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

Somerset County covers 26 ZIP codes including: 04478, 04911, 04912, 04920, 04923, 04924, 04925, 04929 and 18 more

Somerset County Design Temperatures

Official ASHRAE design temperatures for Somerset County, ME, used for accurate Manual J load calculations.

Winter 99% Design Temp
-9°F
Heating load calculation baseline
Summer 1% Design Temp
81°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 Somerset 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 Somerset County, ME

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

Recommended HVAC Equipment for Somerset 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 Maine

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

Get Free Manual J Calculations for Somerset County

Upload your Somerset County blueprint and get a professional Manual J load calculation using official Zone 6A design temperatures. First report is FREE.

Somerset County design temps
Zone 6A compliant
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