TDI’s legacy map shows the previous zone designations for designated catastrophe areas along the Gulf Coast of Texas. The map is available on the TDI website.

The Texas Department of Insurance (TDI) adopted the 2018 International Building Code (IBC) and 2018 International Residential Code (IRC) effective September 1, 2020. Dr. Paul Bove, an engineer with the TDI, explained to members of the Fenestration & Glazing Industry Alliance (FGIA) what has changed and how those changes impact glazing and fenestration manufacturers in a recent webinar titled, “TDI Requirements for Fenestration – New Code Update.” He spoke to members in January 2020 about requirements for fenestration products.

TDI now requires that construction be certified to the 2018 IBC and IRC to be eligible for insurance under its windstorm program, which is a voluntary program for certain areas along the Gulf Coast of Texas where it can be difficult to obtain windstorm insurance through the voluntary market.

The new map, updated after the adoption of the 2018 IBC and IRC, shows the designated catastrophe areas without windspeeds.

Bove first explained what has not changed since the new code adoption. That includes the designated catastrophe areas that are eligible for the program and the eligibility requirements. Areas not already included in the list of first tier counties can petition to be included if they believe they are having a difficult time obtaining windstorm insurance coverage through the voluntary market. However, jurisdiction requirements may be different from what the TDI requires.

When the commissioner made the decision to adopt the 2018 code editions, the windspeeds were not adopted. The former windspeed zones (Inland II, Inland I and the Seaward zones) no longer exist. TDI now uses risk category zones to determine the windspeed requirements. Those looking to find out which category a location falls into can look it up using the Applied Technology Council Hazards by Location web-based tool at A location can be found using an address or coordinates. The minimum required basic windspeeds for TDI’s windstorm program are based on the basic windspeed maps from ASCE 7-16 and windspeed contours. They are as follows:

  • Risk category I (approximately 130 mph);
  • Risk category II (approximately 140 mph); and
  • Risk Category IV (approximately 150 mph).

An area is in a windborne debris region if the basic windspeed is greater than or equal to 140 mph. Most of the designated catastrophe area falls under Risk Category II and is within the windborne debris region, which requires additional protection of glazed openings. The TDI previously required that the Seaward zone have protection for both glazed and opaque openings but the new code adoption drops the opaque opening windborne debris requirement.

An inspector will need to determine windspeed and verify design pressure requirements for fenestration using the IBC/IRC/ASCE 7 tables. However, TDI also provides guidance.

Bove explained that while the windspeeds are higher than in the previous code adoption, the design pressure requirements are similar.

He also explained that when it comes to windborne debris protection, the code doesn’t specify that impact-resistant products be used, though that may be the most efficient option. Non-impact-resistant products such as wood structural panels or proprietary shutter systems can be used if tested to the standards referenced in the codes. For Risk Category IV structures, missile level E is required for enhanced protection.

Products that are currently certified to older editions of NAFS or ASTM E 1886/E 1996 as permitted by the inspection agency may be listed with TDI. However, the design drawings need to be updated to reference the 2018 IBC and IRC. Bove pointed out that submittals that include design drawings provide a wealth of guidance to inspectors and consumers.

TDI now accepts product submittals electronically. The TDI website states this will be effective February 1, 2021 but manufacturers can use this submittal method now.

Bove explained some common submittal issues, which include:


  • Label(s) are not provided as is to be applied to product.
  • Label information does not match certification information.

Certification Documents

  • Certification documents are not provided.
  • Certification documents are expired.
    • TDI accepts certifications that have been extended.

Test Reports

  • The installation section is vague.
    • Substrate type is not specified.
    • Fastener/anchor requirements are not specified.
  • Side hinged doors hardware section is vague.
    • Hinge attachment method is not specified.
    • The manufacturer, series/model of deadbolt, locksets, multi-point locks, shoot bolts are not specified.
    • Strike plates and attachment method are not specified.
  • Side hinged doors threshold requirements or swing direction are not specified.


  • Drawings do not reference TDI adopted building specifications.
  • Drawings are not sealed by a Texas licensed PE with their Texas seal.
  • Side hinged door hardware is not specified, daylight opening sizes of glazing are not specified or threshold is not specified.
  • Fastener specs for substrate(s) are not specified.

Mullion Drawings

  • The attachment of fenestration to mullions is not specified.
  • The attachment of vertical mullions to horizontal mullions is not specified.


  • The analysis does not reference TDI adopted building specifications.
  • The analysis is not sealed by a Texas licensed PE with their Texas seal.

Inspector Issues

  • The label applied to a product does not match the one listed in the TDI evaluation report.
  • The wrong label is applied to product.
    • Field labelling is required.

1 Comment

  1. The wind speed of 140 MPH, is that ULT or ASD? We see a lot of 140MPH ULT but reduced to ASD makes a lot of the wind speeds well below the required Impact glazing requirement.

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