HVAC Calculators
Turn specified duct dimensions and run lengths into HVAC material quantities. These free HVAC calculators help mechanical contractors organize straight-duct takeoffs and related allowances.
Available calculators
1 live toolTake off rectangular and round straight duct across multiple or identical runs.
- Duct LF and surface area
- Approximate sheet-metal weight
- Insulation, liner and packages
- Fitting counts, hangers and sections
Fittings are counted separately; fitting-development metal area and weight are excluded.
Open CalculatorUse specified ductwork inputs
Enter dimensions and gauge from the mechanical plans and specifications. Review fabrication allowance, insulation coverage and hanger assumptions for the defined runs.
This is not an airflow-based duct sizer. It does not choose the required gauge or design supports.
Coordinate the mechanical drawing set
A complete HVAC takeoff reviews equipment schedules, ductwork, piping, controls and related details. Straight-duct quantities alone do not describe the complete mechanical scope.
Use the calculator for run-level checks and drawing-based estimating to organize equipment and materials across systems and locations.
Need a Complete HVAC Takeoff?
Send your drawings, specifications and scope to Build IT Estimating for a project takeoff or estimate.
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