Calculadora de Dimensionamiento de DuctosFórmula

## Duct Sizing by Velocity

**A = CFM / Velocity**

**Diameter = 2 x sqrt(A / pi)**

Convert the area to diameter for round ducts. For residential trunk lines, maximum velocity of 700 ft/min keeps noise low. Branch runs can go up to 600 ft/min. Round up to the next standard duct size.

Ejemplo Resuelto

400 CFM at a max velocity of 700 ft/min.

  1. Area = 400 / 700 = 0.571 sq ft = 82.3 sq in
  2. Diameter = 2 x sqrt(0.571 / pi) x 12 = 10.2 in
  3. Use a 10-inch round duct (or 12-inch for lower velocity).