ASCE 7-22 · VELOCITY PRESSURE + DESIGN PRESSURE
Wind Load Pressure Calculator
Wind load pressure is how hard the wind pushes and pulls on a building surface, in pounds per square foot. Under ASCE 7-22 it is a two-step calculation — a velocity pressure from the site’s wind speed, then a design pressure that applies the shape and internal-pressure coefficients. Our free calculator runs it from a ZIP code, including the Florida High-Velocity Hurricane Zone.
No signup. Enter a ZIP → get the ASCE 7-22 design wind speed → get component & cladding design pressure. A free MWFRS calculator is available too.
HOW WIND LOAD PRESSURE IS CALCULATED
Two steps, every time
Whatever the surface, ASCE 7-22 gets to a design pressure the same way: first turn the site wind speed into a velocity pressure, then apply the coefficients that describe the building.
STEP 1 · VELOCITY PRESSURE
qz = 0.00256 × Kz × Kzt × Kd × Ke × V²
The dynamic pressure of the wind at height, in psf. V is the mapped ASCE 7-22 basic wind speed for the site.
STEP 2 · DESIGN PRESSURE
p = q(GCp − GCpi) (C&C) · p = qG Cp − qi(GCpi) (MWFRS)
Multiply the velocity pressure by the external shape coefficient, then subtract the worst-case internal pressure.
Kz
Exposure coefficient — how open the terrain is (B, C, or D) and the height above grade.
Kzt
Topographic factor — wind speed-up over hills, ridges, and escarpments (1.0 on flat ground).
Kd
Directionality factor — 0.85 for buildings, reflecting that peak wind and peak coefficient rarely align.
Ke
Ground elevation factor — air density adjustment for altitude (1.0 is always conservative).
V
Basic wind speed — the mapped 3-second-gust design speed for the location and risk category.
Kd is carried in the velocity pressure here to match how our engines and reports compute it end-to-end — the design pressure is identical either way.
TWO PRESSURE SYSTEMS · ONE BUILDING
Which wind load pressure do you need?
Every building is checked two ways, because the wind loads a whole frame differently than it loads one panel. Both come from the same velocity pressure; they differ in the coefficients.
Components & Cladding (C&C)
Pressure on the elements that take wind directly — windows, doors, wall panels, roof panels, and their fasteners. Corners and edges see the highest suction. Uses GCp by zone and effective wind area (Ch. 30).
DEEP DIVE →Main Wind Force Resisting System (MWFRS)
Pressure on the whole structural system — frames, shear walls, and diaphragms — as area-averaged loads that produce base shear and overturning. Uses G Cp on the building faces (Ch. 27).
DEEP DIVE →New to the split? Start with C&C vs MWFRS explained.
BY SURFACE
Where the pressure lands
Each surface reads a different coefficient off the same velocity pressure. Jump to the detail you need.
Windows & Doors
Design pressure (DP) ratings for openings — the number that has to match the product.
OPENINGSRoofs & Uplift
Corner and edge suction that governs roof panels, membranes, and fasteners.
UPLIFTWalls & Cladding
Interior (Zone 4) and corner (Zone 5) wall pressures for panels and anchors.
WALLSFLORIDA HIGH-VELOCITY HURRICANE ZONE
Where wind load pressure is highest in the nation
In Miami-Dade and Broward — the HVHZ — the Florida Building Code sets design wind speeds of roughly 170–175 mph, so the pressures on every opening and panel run far above the rest of the country. Our calculator applies the HVHZ speeds and county overrides automatically, so the design pressure is right for the jurisdiction, not a generic estimate.
RUN THE NUMBERS
Your wind load pressure, in about a minute
Skip the tables. Enter a ZIP and building details — the calculator pulls the ASCE 7-22 design wind speed, applies Kz, Kzt, Kd, Ke, GCp, and GCpi, and returns the design pressure zone by zone. Free for a single component; full projects and an Engineering Report are on the calculators.
Need the whole building, roofs, or specialty structures? See all calculators & pricing →
COMMON QUESTIONS
Wind load pressure, answered
How is wind load pressure calculated?
In two steps under ASCE 7-22. First the velocity pressure qz = 0.00256 KzKztKdKeV² converts the mapped wind speed into psf. Then the design pressure applies the shape coefficient and subtracts the internal pressure: p = q(GCp−GCpi) for components & cladding.
What is design wind pressure?
The design wind pressure is the psf value a surface must be built to resist, after the velocity pressure is multiplied by the external coefficient and the worst-case internal pressure is removed. Positive means inward, negative means outward suction — and suction usually governs at corners.
Is wind load pressure the same as wind speed?
No. Wind speed is an input; pressure is the output. Because pressure grows with the square of speed, small speed increases produce large pressure increases — which is why HVHZ pressures are so high.
C&C or MWFRS — which pressure do I use?
Both. Components & cladding pressure sizes individual panels, windows, and fasteners; MWFRS pressure sizes the overall structural system. They use the same velocity pressure but different coefficients. See C&C vs MWFRS.
KEEP READING
Related wind load guides
Components & Cladding
Zones, GCp coefficients, effective wind area, and a worked example.
C&CMWFRS Wind Pressure
Whole-building pressures, base shear, and overturning.
MWFRSWind Speed by ZIP
Find the ASCE 7-22 design wind speed — the V that starts every pressure.
V INPUTUltimate vs Nominal
LRFD vs ASD pressures and the 0.6W conversion.
ASD / LRFDWindow & Door Pressure
Design pressure (DP) ratings for openings.
DPFlorida HVHZ
Miami-Dade & Broward: the highest design pressures in the country.
HVHZ