Get accurate climate zone data, IECC requirements, and design temperatures for precise Manual J load calculations. 100% free for contractors.
Instant climate zone lookup with IECC specs and design temps
Explore all 14 IECC climate zones. Learn about R-value requirements, design temperatures, and equipment recommendations for each zone.
Very cold climate with extreme winter conditions. Extreme heating requirements, minimal cooling needs.
Subarctic climate with extreme cold. Maximum heating requirements, no cooling needed.
Cooling-dominated climate with extreme heat and high humidity year-round. Minimal heating requirements.
Cooling-dominated with hot, humid summers and mild winters. Significant cooling loads with moderate heating needs.
Hot, dry climate with extreme summer heat and low humidity. Cool winters with minimal heating requirements.
Mixed climate with warm, humid summers and cool winters. Balanced heating and cooling needs.
Warm climate with low humidity, hot summers and cool winters. Moderate heating and cooling loads.
Mild, marine climate with cool summers and mild winters. Moderate heating needs, minimal cooling.
True mixed climate with hot, humid summers and cold winters. Equal emphasis on heating and cooling.
Mixed climate with low humidity, warm summers and cold winters. Significant heating and cooling needs.
Marine climate with mild, wet winters and cool summers. Moderate heating needs, minimal cooling.
Heating-dominated climate with cold winters and warm, humid summers. High heating loads, moderate cooling needs.
Heating-dominated with cold, dry winters and warm summers. High heating loads in winter, moderate cooling needs.
Cold climate with very cold winters and warm summers. Very high heating loads, moderate cooling needs.
Cold, dry climate with very cold winters and mild summers. Extreme heating requirements, minimal cooling.
Find climate zone information for your state. Get zone maps, city data, and IECC requirements for all major cities.
Using the correct climate zone data is critical for accurate HVAC system sizing, energy code compliance, and long-term equipment performance.
Climate zone data determines design temperatures, humidity levels, and load factors for precise heating and cooling calculations.
Each climate zone has specific insulation requirements (R-values), window specs (U-factor, SHGC), and infiltration standards.
Climate zones guide equipment selection - from high-SEER AC in Zone 1 to high-AFUE furnaces in Zone 7. Right sizing prevents comfort issues and callbacks.
Get detailed climate zone information for major cities across the US
Now that you know your climate zone, get a professional Manual J load calculation based on your exact location. First report is 100% FREE.