Which 14 counties need windstorm certification?

The Texas Department of Insurance designates a catastrophe area along the coast. Inside it, a structure that needs wind and hail coverage through the Texas Windstorm Insurance Association has to be built and inspected to the building specifications TDI adopts. The certificate of compliance TDI issues is called a WPI-8.

The counties

Aransas, Brazoria, Calhoun, Cameron, Chambers, Galveston, Jefferson, Kenedy, Kleberg, Matagorda, Nueces, Refugio, San Patricio and Willacy. Certain municipalities in Harris County east of State Highway 146 are also included.

When it applies

The requirement has been in force since 1 January 1988, following legislation passed in 1987. It covers new construction, alterations, additions, and roof repair or replacement.

What it means for a metal building

In these counties the inspection is not optional if you want TWIA coverage on the structure. Plan for engineered drawings, a heavier anchoring specification and an inspection signed off by someone TDI accepts. Get that priced in at quote time, because a quote written for an inland county will not carry it.

Everywhere else

If your land is not in one of those counties, windstorm certification does not apply to you. Your wind requirement is still real, but it comes from the design wind speed at your address under ASCE 7, not from TDI.

Sources

Last checked September 2026. Something out of date? Tell us and we will re-check it.