Net Free Area Calculator
Calculate the net free area for ventilation, louvers, grilles, and air vents. Determine airflow capacity based on dimensions and free area percentage.
Step 1: Vent Dimensions
Understanding Free Area
Free area percentage represents the unobstructed opening through which air can flow. Standard louvers typically have 50-75% free area, while grilles may have 40-60%.
Step 2: Calculation Options
About Net Free Area
Net free area is calculated as: (Width × Height) × (Free Area % / 100). This value is crucial for determining ventilation capacity and meeting building code requirements.
Net Free Area Results
Net Free Area Per Vent
Vent Type Comparison
| Vent Type | Free Area % | Net Free Area | Airflow Capacity |
|---|
Area Breakdown
Net Free Area Formula
Net Free Area = (Width × Height) × (Free Area % / 100)
To calculate net free area: Multiply the vent dimensions to get gross area, then multiply by the free area percentage (as decimal). Multiply by number of vents for total area.
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