Furnace Size Calculator

Calculate Furnace Size Requirements

About Furnace Size Calculator

This calculator determines the proper furnace size for your home based on square footage, climate zone, insulation level, and ceiling height.

Climate Zones:

  • Zone 1: Hot climates (Florida, Texas)
  • Zone 2: Warm climates (California, Arizona)
  • Zone 3: Moderate climates (Mid-Atlantic)
  • Zone 4: Cool climates (Northeast, Midwest)
  • Zone 5: Cold climates (Alaska, Northern states)

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