Zone 6ACold (Zone 6)

Climate Zone 6A - Cold, Humid

Short warm summers and long cold winters. Very high heating loads. This climate zone encompasses parts of Minnesota, Wisconsin, Michigan, Maine, Vermont, New Hampshire, New York and includes major cities like Minneapolis, Milwaukee, Detroit, Burlington.

Design Temperatures

Winter Design Temperatures

-20°F to 0°F

Used for heating load calculations and equipment sizing

Summer Design Temperatures

75°F to 85°F

Used for cooling load calculations and equipment sizing

Heating & Cooling Degree Days

Heating Degree Days (HDD)

6,000 - 8,500

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

Cooling Degree Days (CDD)

250 - 1,000

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

HVAC System Considerations

Key Considerations

  • Extremely high heating loads
  • Short cooling season
  • Freeze protection essential
  • Snow and ice loads
  • Equipment cold weather performance

Common Equipment

  • High-efficiency gas furnaces
  • Boilers
  • Cold climate heat pumps
  • Radiant heating systems

Energy Code Requirements

Equipment Efficiency

  • SEER 13+ minimum
  • HSPF 8.2+ for heat pumps
  • AFUE 90+ for furnaces
  • Continuous insulation required

Insulation Requirements

Walls:R-20 to R-21
Ceiling:R-49 to R-60
Floor:R-25 to R-30

Quick Reference

Zone:6A
Temperature:Cold
Moisture:Moist (A)
States:7
Cities:5

Calculate Load

Use our load calculators with the design temperatures and requirements specific to Zone 6A.