Climate ZonesArizonaMaricopa County

What Climate Zone is Maricopa County, AZ?

Maricopa County is in IECC Climate Zone 2B (Hot - Dry). Get accurate Manual J load calculations with official ASHRAE design temperatures for Maricopa County.

IECC Climate Zone
2B
Winter 99% Design
24°F
Summer 1% Design
111°F
ZIP Codes
209
Cities
1

Maricopa County, Arizona is classified under IECC Climate Zone 2B (Hot - Dry), a cooling-dominated region with dry moisture conditions. With 209 ZIP codes and 1 communities, every HVAC installation in Maricopa County must use the ASHRAE design temperatures of 24°F (99% winter heating) and 111°F (1% summer cooling) for accurate Manual J load calculations.

As a cooling-dominated zone, controlling solar heat gain is essential in Maricopa County. Windows must have an SHGC of 0.25 or lower, along with R-13 wall and R-30 ceiling insulation. Proper sizing prevents oversized AC systems that short-cycle and waste energy.

Maricopa County Insulation Requirements (IECC 2021)

Minimum insulation R-values and window performance for Climate Zone 2B in Maricopa County, AZ.

Building ComponentMinimum RequirementUnit
Ceiling / Attic InsulationR-30R-value
Wall InsulationR-13R-value
Floor InsulationR-13R-value
Window U-Factor0.4BTU/hr-ft²-°F
Window SHGC0.25Coefficient
Air Infiltration0.25ACH50

Maricopa County HVAC Contractors: Get Your Free Manual J Report

Climate Zone 2B requires precise load calculations. Upload your Maricopa County blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with Maricopa County's exact design temperatures (24°F winter / 111°F summer).

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Verify Your Maricopa County ZIP Code

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

Maricopa County covers 209 ZIP codes including: 85001, 85002, 85003, 85004, 85005, 85006, 85007, 85008 and 201 more

Maricopa County Design Temperatures

Official ASHRAE design temperatures for Maricopa County, AZ, used for accurate Manual J load calculations.

Winter 99% Design Temp
24°F
Heating load calculation baseline
Summer 1% Design Temp
111°F
Cooling load calculation baseline
Summer Wet Bulb
71°F
Latent load (humidity) calculation

IECC Zone 2B Insulation Requirements

Minimum insulation and window requirements for Maricopa County per IECC 2021 energy code.

Wall Insulation:R-13
Roof/Ceiling:R-30
Floor Insulation:R-13
Window U-Factor:0.4
Window SHGC:0.25

Climate Zone 2B: Hot - Dry - Hot, dry climate with extreme summer heat and low humidity. Cool winters with minimal heating requirements.

Cities in Maricopa County, AZ

1 cities and communities in Maricopa County share Climate Zone 2B requirements.

Recommended HVAC Equipment for Maricopa County

Heating Systems

Gas furnace
Heat pump
Electric resistance
Typical AFUE
80-90%

Cooling Systems

AC (14-16 SEER)
Evaporative cooling (swamp cooler)
Typical SEER
14-16 SEER

Nearby Counties in Arizona

Compare climate zones with other counties in Arizona. Different zones require different HVAC equipment sizing.

Get Free Manual J Calculations for Maricopa County

Upload your Maricopa County blueprint and get a professional Manual J load calculation using official Zone 2B design temperatures. First report is FREE.

Maricopa County design temps
Zone 2B compliant
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