What Climate Zone is San Miguel, Colorado?

San Miguel is in IECC Climate Zone 6B (Cold - Dry). Get accurate Manual J load calculations with official design temperatures for San Miguel.

Climate Zone
6B
Winter Design
-13°F
Summer Design
91°F
ZIP Codes
5

San Miguel, Colorado falls within IECC Climate Zone 6B (Cold - Dry), a heating-dominated region with dry moisture conditions. HVAC contractors working in San Miguel must use the official ASHRAE design temperatures of -13°F (99% winter) and 91°F (1% summer) when performing Manual J load calculations. These values represent the outdoor conditions your heating and cooling system must handle 99% and 1% of the year, respectively — ensuring proper equipment sizing without costly over- or under-sizing.

Because Zone 6B is heating-dominated, insulation levels are critical. San Miguel homes require a minimum of R-20 wall insulation, R-49 ceiling insulation, and windows with a U-factor of 0.3 or lower per the IECC 2021 energy code.

San Miguel Insulation Requirements (IECC 2021)

Minimum insulation R-values and window performance requirements for Climate Zone 6B in San Miguel, Colorado.

Building ComponentMinimum RequirementUnit
Ceiling / Attic InsulationR-49R-value
Wall InsulationR-20R-value
Floor InsulationR-30R-value
Window U-Factor0.3BTU/hr-ft²-°F
Window SHGC0.4Coefficient
Air Infiltration0.15ACH50

San Miguel HVAC Contractors: Get Your Free Manual J Report

Climate Zone 6B requires precise load calculations. Upload your San Miguel blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with San Miguel's exact design temperatures (-13°F winter / 91°F summer).

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Verify Your San Miguel ZIP Code

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

San Miguel covers 5 ZIP codes: 81325, 81423, 81426, 81430, 81435

San Miguel Design Temperatures

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

Winter 99% Design Temp
-13°F
Summer 1% Design Temp
91°F
Summer Wet Bulb
62°F

IECC Requirements for Zone 6B

Minimum insulation and window requirements for San Miguel 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 San Miguel

Heating Systems

Gas furnace (96%+ AFUE)
Boiler
Typical AFUE
96-98%

Cooling Systems

AC (13-14 SEER, often optional)
Typical SEER
13-14 SEER

Get Free Manual J Calculations for San Miguel

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San Miguel design temps
Zone 6B compliant
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