Climate ZonesCaliforniaMarin

Marin, California HVAC Climate Zone

Marin is located in IECC Climate Zone 3C (Warm - Marine). Get accurate Manual J load calculations with official design temperatures for Marin.

Climate Zone
3C
Winter Design
41°F
Summer Design
81°F
ZIP Codes
28

Marin HVAC Contractors: Get Your Free Manual J Report

Climate Zone 3C requires precise load calculations. Upload your Marin blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with Marin's exact design temperatures (41°F winter / 81°F summer).

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Verify Your Marin ZIP Code

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

Marin covers 28 ZIP codes: 94901, 94903, 94904, 94920, 94924, 94925, 94929, 94930, 94933, 94937 and 18 more

Marin Design Temperatures

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

Winter 99% Design Temp
41°F
Summer 1% Design Temp
81°F
Summer Wet Bulb
63°F

IECC Requirements for Zone 3C

Minimum insulation and window requirements for Marin per IECC 2021.

Wall Insulation:R-20
Roof/Ceiling:R-30
Floor Insulation:R-19
Window U-Factor:0.32
Window SHGC:0.4

Energy Code: 2022 Title 24

Recommended HVAC Equipment for Marin

Heating Systems

Gas furnace
Heat pump
Typical AFUE
90-95%

Cooling Systems

AC (often optional)
Heat pump
Typical SEER
14 SEER

Related Climate Zone Pages

Learn More About
Climate Zone 3C
View All Zones in
California
HVAC Permits for
Marin, California

Get Free Manual J Calculations for Marin

Upload your Marin blueprint and get a professional Manual J load calculation using official Zone 3C design temperatures. First report is FREE.

Marin design temps
Zone 3C compliant
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