St. Clair, Michigan HVAC Climate Zone

St. Clair is located in IECC Climate Zone 5A (Cool - Humid). Get accurate Manual J load calculations with official design temperatures for St. Clair.

Climate Zone
5A
Winter Design
0°F
Summer Design
91°F
ZIP Codes
21

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

Climate Zone 5A requires precise load calculations. Upload your St. Clair blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with St. Clair's exact design temperatures (0°F winter / 91°F summer).

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Verify Your St. Clair ZIP Code

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

St. Clair covers 21 ZIP codes: 48001, 48002, 48006, 48014, 48022, 48023, 48027, 48028, 48032, 48039 and 11 more

St. Clair Design Temperatures

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

Winter 99% Design Temp
0°F
Summer 1% Design Temp
91°F
Summer Wet Bulb
75°F

IECC Requirements for Zone 5A

Minimum insulation and window requirements for St. Clair 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: 2020 IECC

Recommended HVAC Equipment for St. Clair

Heating Systems

Gas furnace (95%+ AFUE)
Boiler
Heat pump (cold climate)
Typical AFUE
95-98%

Cooling Systems

AC (13-16 SEER)
Heat pump
Typical SEER
13-16 SEER

Get Free Manual J Calculations for St. Clair

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St. Clair design temps
Zone 5A compliant
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