Climate ZonesIllinoisLee

Lee, Illinois HVAC Climate Zone

Lee is located in IECC Climate Zone 5A (Cool - Humid). Get accurate Manual J load calculations with official design temperatures for Lee.

Climate Zone
5A
Winter Design
0°F
Summer Design
91°F
ZIP Codes
14

Lee HVAC Contractors: Get Your Free Manual J Report

Climate Zone 5A requires precise load calculations. Upload your Lee blueprint and get a professional Manual J report in 60 seconds— first report is FREE. Pre-loaded with Lee's exact design temperatures (0°F winter / 91°F summer).

Claim Free Report
No credit card required

Verify Your Lee ZIP Code

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

Lee covers 14 ZIP codes: 60530, 60553, 61006, 61021, 61031, 61042, 61057, 61310, 61318, 61324 and 4 more

Lee Design Temperatures

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

Winter 99% Design Temp
0°F
Summer 1% Design Temp
91°F
Summer Wet Bulb
75°F

IECC Requirements for Zone 5A

Minimum insulation and window requirements for Lee 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 Lee

Heating Systems

Gas furnace (95%+ AFUE)
Boiler
Heat pump (cold climate)
Typical AFUE
95-98%

Cooling Systems

AC (13-16 SEER)
Heat pump
Typical SEER
13-16 SEER

Related Climate Zone Pages

Learn More About
Climate Zone 5A
View All Zones in
Illinois
HVAC Permits for
Lee, Illinois

Get Free Manual J Calculations for Lee

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

Lee design temps
Zone 5A compliant
Ready in 60 seconds
Upload Blueprint → Get Free Report

Join 10,000+ Lee contractors who trust AutoHVAC