Climate ZonesMinnesotaSt. Louis

St. Louis, Minnesota HVAC Climate Zone

St. Louis is located in IECC Climate Zone 7 (Very Cold). Get accurate Manual J load calculations with official design temperatures for St. Louis.

Climate Zone
7
Winter Design
-18°F
Summer Design
87°F
ZIP Codes
44

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

Climate Zone 7 requires precise load calculations. Upload your St. Louis blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with St. Louis's exact design temperatures (-18°F winter / 87°F summer).

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Verify Your St. Louis ZIP Code

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

St. Louis covers 44 ZIP codes: 55602, 55702, 55703, 55705, 55706, 55708, 55710, 55711, 55713, 55717 and 34 more

St. Louis Design Temperatures

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

Winter 99% Design Temp
-18°F
Summer 1% Design Temp
87°F
Summer Wet Bulb
70°F

IECC Requirements for Zone 7

Minimum insulation and window requirements for St. Louis per IECC 2021.

Wall Insulation:R-20
Roof/Ceiling:R-60
Floor Insulation:R-38
Window U-Factor:0.3
Window SHGC:0.45

Energy Code: 2020 IECC

Recommended HVAC Equipment for St. Louis

Heating Systems

Gas furnace (97%+ AFUE)
Boiler
Cold climate heat pump with backup
Typical AFUE
97-98.5%

Cooling Systems

AC (minimal, 13 SEER)
Typical SEER
13 SEER

Related Climate Zone Pages

Learn More About
Climate Zone 7
View All Zones in
Minnesota
HVAC Permits for
St. Louis, Minnesota

Get Free Manual J Calculations for St. Louis

Upload your St. Louis blueprint and get a professional Manual J load calculation using official Zone 7 design temperatures. First report is FREE.

St. Louis design temps
Zone 7 compliant
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