ASCE 7-22 · BASIC WIND SPEED V
Find the wind speed V for your location
Every wind load starts with one number: the basic wind speed V at your site. It is the ultimate 3-second gust at 33 ft in Exposure C — and it is site-specific, never a single national figure.
PICK YOUR METHOD
Three ways to find your V
All three return the same parameter — the ultimate 3-sec gust at 33 ft, Exposure C. Pick the one that fits how precise you need to be.
ASCE 7 Hazard Tool
The official site-specific lookup. Enter latitude/longitude and it returns V for each risk category.
SITE-SPECIFIC · LAT/LONGASCE 7-22 Maps
Read V from the printed contour maps by region — then pick the map that matches your risk category.
CONTOURS · BY REGIONVelocity finder by ZIP
Type a ZIP and our finder returns ASCE 7-22 wind speeds plus city, county, and exposure — pre-filled.
FASTEST · BY ZIP CODETHE LOOKUP, STEP BY STEP
How to look up V
Four steps turn a project address into the design wind speed you carry into the rest of ASCE 7.
Fix your location
Get the exact site — address, ZIP, or latitude/longitude. Precision matters near coastlines and contour lines.
Set the risk category
Risk Category I–IV decides which map you read. Higher category = longer return period = higher V.
Read & interpolate V
Find your site between contours and interpolate linearly. The tools above remove the interpolation guesswork.
Note the exposure
V is mapped at 33 ft in Exposure C. Your actual site (B, C, or D) is applied later through Kz, not the map.
WHICH MAP SELECTS YOUR V
Risk category picks the return-period map
ASCE 7-22 has no wind importance factor. Instead, your risk category sends you to a different map with a different mean recurrence interval (MRI). There is no fixed multiplier between them — actual mph varies by location.
| Risk Category | Map / MRI | Typical occupancy | Effect on V |
|---|---|---|---|
| I | 300-year MRI | Minor agricultural & storage, low hazard to life | Lowest speed map |
| II | 700-year MRI | Homes, offices, retail — most buildings | Standard map |
| III | 1,700-year MRI | Assembly >300, schools, jails, power | Higher speeds |
| IV | 3,000-year MRI | Hospitals, fire/police/EOC, shelters | Highest speeds |
Higher risk category → longer return period → higher design wind speed → higher loads. The relationship is qualitative — read V straight off the map for your category; do not apply an importance-factor multiplier.
BEFORE YOU START
What you need to look up V
Have these four inputs ready and any of the three methods returns a clean answer.
Project location
Address, ZIP, or lat/long for the exact build site.
Risk category
I, II, III, or IV — it selects which speed map you read.
ASCE 7 edition
Confirm the edition your jurisdiction adopted — it sets the maps.
Exposure category
B, C, or D for the site — applied after V, through Kz.
Example map readings vary by site: a coastal South Florida site commonly lands around 170–180 mph (Risk II), while sheltered interior sites read much lower. Treat any printed number as an example that varies by site — always read V for your own coordinates.
GET YOUR NUMBER
Get the wind speed for your ZIP
Skip the map interpolation. The velocity finder returns ASCE 7-22 wind speeds with city, county, and exposure pre-filled.