What Climate Zone is Millard, Utah?

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

Climate Zone
5B
Winter Design
-7°F
Summer Design
91°F
ZIP Codes
11

Millard, Utah falls within IECC Climate Zone 5B (Cool - Dry), a heating-dominated region with dry moisture conditions. HVAC contractors working in Millard must use the official ASHRAE design temperatures of -7°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 5B is heating-dominated, insulation levels are critical. Millard 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.

Millard Insulation Requirements (IECC 2021)

Minimum insulation R-values and window performance requirements for Climate Zone 5B in Millard, Utah.

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

Millard HVAC Contractors: Get Your Free Manual J Report

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

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Verify Your Millard ZIP Code

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

Millard covers 11 ZIP codes: 84624, 84631, 84635, 84636, 84637, 84638, 84640, 84649, 84656, 84728 and 1 more

Millard Design Temperatures

Official ASHRAE design temperatures for Millard, 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 Millard 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 Millard

Heating Systems

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

Cooling Systems

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

Get Free Manual J Calculations for Millard

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Millard design temps
Zone 5B compliant
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