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HVAC Duct Sizing Calculator helps contractors and tradespeople accurately size, spec, and estimate materials and systems.

Формула

Duct Area = CFM / (FPM velocity) where FPM = 700-900 for mains

Водич корак по корак

  1. 1Calculate required CFM per room, size duct for target velocity
  2. 2Apply the formula using your project measurements
  3. 3Add required safety factors or waste allowances per code

Worked Examples

Инпут
400 CFM, 800 FPM target
Резултат
Area = 400/800 = 0.5 sf → 8×9 inch duct

Common Mistakes to Avoid

  • Not applying code-required safety factors or derating
  • Forgetting to account for waste and cut losses in material estimates

Подешавања