Wind Pressure on Vent Calculator
Wind-driven pressure and natural ventilation flow.
Enter your values
ⓘ Live results
Results
- Wind pressure
- 0.221 psf
- In inches wc
- 0.0425
- In Pa
- 10.59
- Estimated airflow
- 2,218 CFM
- Effectiveness factor
- 0.35 (oblique wind)
Quick answer
Wind pressure grows with the square of wind speed and is modified by a surface pressure coefficient.
P = 0.00256 x V² x Cp (psf, mph)
How to use the Wind Pressure on Vent Calculator
- 1Enter the design wind speed at the building.
- 2Use +0.6 to +0.8 for windward faces and -0.3 to -0.6 for leeward.
- 3Cross ventilation needs openings on both faces to realise the flow.
Worked example
Using the values the calculator loads with:
Inputs
- Wind speed12 mph
- Pressure coefficient0.6
- Opening area6 sq ft
Results
- Wind pressure0.221 psf
- In inches wc0.0425
- In Pa10.59
- Estimated airflow2,218 CFM
- Effectiveness factor0.35 (oblique wind)
Frequently asked questions
Why 0.35 not 0.55?
0.55 applies when wind is perpendicular; 0.35 covers typical oblique angles over a year.
Wind or stack effect?
Wind dominates most of the year; stack effect takes over on still, cold days.
About this calculator
- Built and reviewed by James Whitfield · How we build and test calculators
- Report an error
Results are estimates for general information. For medical, legal, structural or financial decisions, confirm with a qualified professional.