Illinois HVAC Load Calculation Guide
Free HVAC load calculation guide for Illinois. Review climate zones, design temperatures, building code context, and local calculator resources for Chicago, Aurora, Rockfordand 2 more cities.
By HVAC Load Calculate Team — Licensed HVAC professionals
Need HVAC installation in Illinois?
Compare contractors, costs, and code requirements statewide.
Start with the Free Illinois Load Calculator
Use our residential or commercial calculator to estimate loads with Illinois-relevant climate conditions in mind.
Illinois Design Temperatures
Winter Design Temperature
-8°F
Used for heating load calculations and equipment sizing across Illinois
Summer Design Temperature
91°F
Used for cooling load calculations and equipment sizing across Illinois
Illinois Building Codes & Requirements
HVAC Requirements
- • High-efficiency equipment
- • Duct testing mandatory
- • Ventilation requirements
Note: Chicago has additional green building requirements
Energy Code
2018 IECC with Illinois amendments
Common Building Types
- • Urban apartments
- • Suburban homes
- • Commercial high-rise
Illinois HVAC Challenges
⚠
Cold winters
⚠
High humidity summers
⚠
Urban heat islands
⚠
Lake effect weather