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Duct Velocity Check
Review duct air velocities against design limits.
HVAC Design SuiteStep 6 of 9
Project & Input Data
Shape
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Your project criterion: enter the value from your governing code, specification or approved supplier data. No standard value is assumed.
Engineering Assumptions
Direct calculation — Continuity equation
- The maximum allowed velocity is a user-entered design criterion; no standard table is assumed.
- All percentages and inputs are user-defined; the calculation is purely arithmetic and assumes no particular code or specification.
Formula Summary
- v = Q(m³/s) ÷ A(m²)
- Margin% = (max − v) ÷ max × 100
Results
Enter your data and press Calculate to see the results.
Engineering Insight
A negative margin means the velocity exceeds the allowed limit and the duct needs to be enlarged.
Recommended Action
Re-check the velocity after any change to the free duct cross-section or the actual airflow.
Next step
This calculator is fully usable as it is. Professional adds saved projects, calculation history and PDF/Excel reports; Premium adds the integrated workflows and the BOQ generator.