Ductwork Sizing Calculator

The Ductwork Sizing Calculator is a vital utility for HVAC system design, helping to determine the appropriate dimensions for ductwork to ensure efficient air distribution. Properly sized ducts are crucial for maintaining desired airflow, minimizing energy consumption, reducing noise, and ensuring overall system performance. This calculator typically uses the constant velocity method, requiring inputs such as airflow rate (CFM) and target air velocity (FPM). It can calculate sizes for both round and rectangular ducts, often providing equivalent dimensions to aid in selection.

Duct Materials & Aspect Ratio: Common duct materials include galvanized steel, aluminum, fiberglass duct board, and flexible ducts. Each has different roughness and insulation properties affecting performance. For rectangular ducts, the aspect ratio (Width/Height) is important; ratios are typically kept below 4:1 (ideally closer to 1:1) for efficiency and to minimize friction.