The Texas Windstorm Insurance Association (TWIA) – the state’s wind and hail insurance catastrophe pool – provides windstorm and hail insurance for structures located in designated catastrophe areas along the coast.
The area encompasses the 14 “First Tier” counties immediately adjacent to the Gulf, plus portions of the large and heavily populated Harris County in which Houston is located.
TDI, which adopts building specifications and evaluates building products for compliance, certifies to the TWIA that structures are insurable against windstorm and hail losses.
TDI currently references the 2006 IBC and IRC, which include NAFS requirements, as the starting point for fenestration requirements. Fenestration products must bear a label that verifies conformance with NAFS and (as applicable) ASTM E1886, ASTM E1996, TAS 201/202 or AAMA 506 for impact resistance.
Submittals to gain product approval must include appropriate test reports, certification and label authorization documents and IBC/IRC-compliant design drawings signed by a registered Texas PE. Engineering analysis is required when alternative substrate, fasteners or installation methods are used.