Texas Windstorm Requirements for Metal Roofing

If your property sits inside the 14 designated Texas coastal counties — Aransas, Brazoria, Calhoun, Cameron, Chambers, Galveston, Jefferson, Kenedy, Kleberg, Matagorda, Nueces, Refugio, San Patricio, Willacy — and a sliver of Harris County east of Highway 146, you're in the Texas Windstorm Insurance Association (TWIA) service area. That means your metal roof has to be inspected and certified by the Texas Department of Insurance (TDI) before any TWIA windstorm policy will attach to it. No WPI-8, no policy, no claim coverage. This page is the practical version of what RISE Roofing does on every TDI-zone metal roof we install.

The WPI-8 in Plain English

The WPI-8 is a one-page form (with engineer's seal) that says: "I inspected this roof during installation, the materials match the manufacturer's tested wind-uplift assembly, and the installation conforms to the Texas Windstorm Building Code (IRC/IBC + TDI amendments)." It must be filed by a TDI-appointed Qualified Inspector or a licensed Texas Professional Engineer. Filing happens through the TDI Catastrophe Operations portal, generally within 30 days of substantial completion. Owner gets a copy, TWIA gets a copy, RISE keeps a copy in your project file.

The Three Inspection Windows You Can't Miss

WPI-8 inspections aren't a one-and-done at the end. To pass, the inspector has to physically observe each phase before it gets covered up:

1. Decking + fastening: 8d ring-shank nails, 6"/6"/12" pattern, plywood seams blocked. Once the underlayment goes down, this is unverifiable — so the inspection has to happen before underlayment.
2. Underlayment + ice/water: Synthetic underlayment with peel-and-stick self-adhering membrane at eaves, valleys, hip/ridge transitions, and all penetrations. Inspection happens before metal goes down.
3. Panel fastening pattern: Final inspection verifies that clip spacing on standing seam (or screw spacing on exposed fastener) matches the wind-uplift assembly tested for the rated speed.

Miss a window and the inspector won't issue the WPI-8. We schedule all three with the inspector before the project even starts.

TDI Wind Speed Tiers — and Which Profile Fits

What Disqualifies a Metal Roof from a WPI-8

• Snap-lock standing seam used inside Tier 1 (mech-lock is required for the higher uplift assembly)
• Exposed-fastener panels installed with the manufacturer's "stock" 24" purlin spacing — TDI Tier 1 typically requires 12–16" spacing
• Missing peel-and-stick at eaves/valleys/penetrations
• Unsealed panel-to-flashing transitions at chimneys, dormers, and skylights
• Substituted clip spacing without an engineer's letter on file

We've inspected metal roofs installed by other contractors that failed WPI-8 review and required full re-fastening — an expensive, avoidable problem.

The RISE Roofing TDI Process

We handle the certification end-to-end on every TWIA-zone metal install: pre-construction engineering letter from a licensed Texas PE, scheduled inspections at all three windows above, manufacturer wind-uplift documentation pulled and filed with the project, and WPI-8 submission to TDI within 7 days of final inspection. The fee is built into our project pricing — no surprise line items.

If you're in Galveston, La Marque, Texas City, Bacliff, Kemah, or eastern Harris County and need a TDI-compliant metal roof, call (832) 345-9527. We'll walk the roof and send a written engineering pre-spec before quoting.