Skip to main content

learn.howToCalculate

learn.whatIsHeading

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

Formule

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

Stapsgewijze handleiding

  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

Uitgewerkte voorbeelden

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

Veelgemaakte fouten om te vermijden

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

Klaar om te berekenen? Probeer de gratis Duct Sizing-rekenmachine

Probeer het zelf →

Instellingen

PrivacyVoorwaardenOver ons© 2026 PrimeCalcPro