Zone 5ACool (Zone 5)

Climate Zone 5A - Cool, Humid

Warm summers and cold winters with humidity. Heating loads dominate. This climate zone encompasses parts of Illinois, Indiana, Ohio, Pennsylvania, New York, Connecticut, Massachusetts and includes major cities like Chicago, Indianapolis, Columbus, Philadelphia.

Design Temperatures

Winter Design Temperatures

-10°F to 10°F

Used for heating load calculations and equipment sizing

Summer Design Temperatures

80°F to 90°F

Used for cooling load calculations and equipment sizing

Heating & Cooling Degree Days

Heating Degree Days (HDD)

4,000 - 6,500

Base 65°F. Higher numbers indicate more heating requirements and longer heating seasons.

Cooling Degree Days (CDD)

500 - 1,500

Base 65°F. Higher numbers indicate more cooling requirements and longer cooling seasons.

HVAC System Considerations

Key Considerations

  • High heating loads
  • Moderate cooling needs
  • Freeze protection critical
  • Humidity control
  • Snow load considerations

Common Equipment

  • Gas furnaces with AC
  • Boilers with separate cooling
  • Heat pumps with backup
  • High-efficiency systems

Energy Code Requirements

Equipment Efficiency

  • SEER 13+ minimum
  • HSPF 7.7+ for heat pumps
  • AFUE 80+ for furnaces
  • Enhanced building envelope

Insulation Requirements

Walls:R-19 to R-21
Ceiling:R-49 to R-60
Floor:R-25 to R-30

Quick Reference

Zone:5A
Temperature:Cool
Moisture:Moist (A)
States:7
Cities:5

Calculate Load

Use our load calculators with the design temperatures and requirements specific to Zone 5A.