Starting September 1, 2020, Windstorm Certificate of Compliance applications (WPI-1) must be certified in accordance with either the 2018 International Residential Code (IRC) or the 2018 International Building Code (IBC). Construction must be certified to be eligible for windstorm insurance coverage through TWIA.
Designated Catastrophe Areas
The Designated Catastrophe Areas that are part of TDI’s windstorm program remain the same. These areas have not changed with the adoption of the new building codes. Construction must be located within the Designated Catastrophe Areas to be eligible for windstorm insurance coverage through TWIA. Refer to the Designated Catastrophe Areas map. Except for Harris County, the entire county of each of the counties on the map are part of the windstorm program. Within Harris County, the structure must be located East of Highway 146 and within the city limits of the cities that are shown on the map.
The required wind speed must be determined for each structure based on the location of the structure. To determine the windspeed requirements for your project you can use web-based tools including Applied Technology Council Hazard by Location, and the ASCE7 Hazard Tool.
Windborne Debris Protection
Most of the Designated Catastrophe Areas are now located within the windborne debris region. The web-based tools listed under wind speeds can be used to determine if a structure is located in an area where windborne debris protection is required. Requirements for windborne debris protection are as specified in the 2018 IRC and the 2018 IBC.