Climate ZonesWashingtonThurston

Thurston, Washington HVAC Climate Zone

Thurston is located in IECC Climate Zone 4C (Mixed - Marine). Get accurate Manual J load calculations with official design temperatures for Thurston.

Climate Zone
4C
Winter Design
29°F
Summer Design
85°F
ZIP Codes
12

Thurston HVAC Contractors: Get Your Free Manual J Report

Climate Zone 4C requires precise load calculations. Upload your Thurston blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with Thurston's exact design temperatures (29°F winter / 85°F summer).

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Verify Your Thurston ZIP Code

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

Thurston covers 12 ZIP codes: 98501, 98502, 98503, 98506, 98512, 98513, 98516, 98530, 98576, 98579 and 2 more

Thurston Design Temperatures

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

Winter 99% Design Temp
29°F
Summer 1% Design Temp
85°F
Summer Wet Bulb
67°F

IECC Requirements for Zone 4C

Minimum insulation and window requirements for Thurston per IECC 2021.

Wall Insulation:R-20
Roof/Ceiling:R-49
Floor Insulation:R-19
Window U-Factor:0.32
Window SHGC:0.4

Energy Code: 2021 IECC

Recommended HVAC Equipment for Thurston

Heating Systems

Gas furnace
Heat pump
Typical AFUE
92-95%

Cooling Systems

AC (optional)
Heat pump
Typical SEER
14 SEER

Related Climate Zone Pages

Learn More About
Climate Zone 4C
View All Zones in
Washington
HVAC Permits for
Thurston, Washington

Get Free Manual J Calculations for Thurston

Upload your Thurston blueprint and get a professional Manual J load calculation using official Zone 4C design temperatures. First report is FREE.

Thurston design temps
Zone 4C compliant
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