Wind Load Calculator
Calculate wind pressure forces per ASCE 7-22 standards
What is the formula for Wind Load?
The basic wind load formula per ASCE 7-22 standards:
q = 0.00256 × Kz × Kzt × V²
Where:
q = Velocity pressure (psf)
Kz = Exposure coefficient
Kzt = Topographic factor
V = Wind speed (mph)
The design wind pressure is then calculated as:
p = q × G × Cp
G = Gust factor (0.85)
Cp = Pressure coefficient
What is Wind Load?
Wind load is the force exerted by wind on structures. Key components:
- Direct pressure on windward surfaces
- Suction forces on leeward surfaces
- Lateral forces affecting structural stability
Proper calculation is crucial for structural design according to building codes (ASCE 7, IBC).
How to calculate wind velocity pressure (q)?
Follow these steps:
- Determine basic wind speed (V) from local building codes
- Select exposure category (B, C, or D)
- Determine topographic factor (Kzt)
- Apply formula: q = 0.00256 × Kz × Kzt × V²
Example Calculation:
V = 120 mph, Kz = 1.0, Kzt = 1.0
q = 0.00256 × 1 × 1 × (120)² = 36.86 psf
How to find total wind load?
Complete calculation process:
- Calculate velocity pressure (q)
- Determine gust factor (G) and pressure coefficient (Cp)
- Calculate design pressure: p = q × G × Cp
- Multiply pressure by surface area: F = p × A
Typical values:
G = 0.85 (for buildings)
Cp = 0.8 (windward wall)
Cp = -0.5 (leeward wall)