St. Croix, Wisconsin HVAC Climate Zone

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

Climate Zone
6A
Winter Design
-9°F
Summer Design
89°F
ZIP Codes
11

St. Croix HVAC Contractors: Get Your Free Manual J Report

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

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Verify Your St. Croix ZIP Code

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

St. Croix covers 11 ZIP codes: 54002, 54007, 54013, 54015, 54016, 54017, 54023, 54025, 54027, 54028 and 1 more

St. Croix Design Temperatures

Official ASHRAE design temperatures for St. Croix, 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 St. Croix 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 St. Croix

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

Get Free Manual J Calculations for St. Croix

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

St. Croix design temps
Zone 6A compliant
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