Climate ZonesOregonPortland

Portland, Oregon HVAC Climate Zone

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

Climate Zone
4C
Winter Design
29°F
Summer Design
85°F
ZIP Codes
41

Portland HVAC Contractors: Get Your Free Manual J Report

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

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Verify Your Portland ZIP Code

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

Portland covers 41 ZIP codes: 97201, 97202, 97203, 97204, 97205, 97206, 97207, 97208, 97209, 97210 and 31 more

Portland Design Temperatures

Official ASHRAE design temperatures for Portland, 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 Portland 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 Portland

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
Oregon
HVAC Permits for
Portland, Oregon

Get Free Manual J Calculations for Portland

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

Portland design temps
Zone 4C compliant
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