Climate ZonesColoradoJefferson

Jefferson, Colorado HVAC Climate Zone

Jefferson is located in IECC Climate Zone 5B (Cool - Dry). Get accurate Manual J load calculations with official design temperatures for Jefferson.

Climate Zone
5B
Winter Design
-7°F
Summer Design
91°F
ZIP Codes
26

Jefferson HVAC Contractors: Get Your Free Manual J Report

Climate Zone 5B requires precise load calculations. Upload your Jefferson blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with Jefferson's exact design temperatures (-7°F winter / 91°F summer).

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Verify Your Jefferson ZIP Code

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

Jefferson covers 26 ZIP codes: 80002, 80003, 80004, 80005, 80007, 80021, 80033, 80123, 80127, 80128 and 16 more

Jefferson Design Temperatures

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

Winter 99% Design Temp
-7°F
Summer 1% Design Temp
91°F
Summer Wet Bulb
63°F

IECC Requirements for Zone 5B

Minimum insulation and window requirements for Jefferson 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: 2021 IECC

Recommended HVAC Equipment for Jefferson

Heating Systems

Gas furnace (95%+ AFUE)
Typical AFUE
95-98%

Cooling Systems

AC (13-15 SEER)
Typical SEER
13-15 SEER

Related Climate Zone Pages

Learn More About
Climate Zone 5B
View All Zones in
Colorado
HVAC Permits for
Jefferson, Colorado

Get Free Manual J Calculations for Jefferson

Upload your Jefferson blueprint and get a professional Manual J load calculation using official Zone 5B design temperatures. First report is FREE.

Jefferson design temps
Zone 5B compliant
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