Climate ZonesVermontWindham

Windham, Vermont HVAC Climate Zone

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

Climate Zone
6A
Winter Design
-9°F
Summer Design
89°F
ZIP Codes
24

Windham HVAC Contractors: Get Your Free Manual J Report

Climate Zone 6A requires precise load calculations. Upload your Windham blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with Windham's exact design temperatures (-9°F winter / 89°F summer).

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Verify Your Windham ZIP Code

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

Windham covers 24 ZIP codes: 05101, 05146, 05148, 05154, 05155, 05158, 05301, 05341, 05342, 05343 and 14 more

Windham Design Temperatures

Official ASHRAE design temperatures for Windham, used for accurate Manual J load calculations.

Winter 99% Design Temp
-9°F
Summer 1% Design Temp
89°F
Summer Wet Bulb
73°F

IECC Requirements for Zone 6A

Minimum insulation and window requirements for Windham per IECC 2021.

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

Energy Code: 2021 IECC

Recommended HVAC Equipment for Windham

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

Related Climate Zone Pages

Learn More About
Climate Zone 6A
View All Zones in
Vermont
HVAC Permits for
Windham, Vermont

Get Free Manual J Calculations for Windham

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

Windham design temps
Zone 6A compliant
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