East of Highway 146 — League City, Seabrook, Kemah, Bacliff, La Porte, the Bolivar Peninsula, the entire Galveston shoreline — the Texas Department of Insurance runs a coastal windstorm building inspection program (WPI-8). Many insurance carriers ask homeowners to hold WPI-8 documentation on anchored backyard structures. This is an educational guide to the program: what WPI-8 is, what inspectors look for, and how we support the process. Homeowners should confirm specific requirements with their insurance carrier.
What WPI-8 actually is
WPI-8 is the Texas Department of Insurance windstorm building inspection form. It is the document some wind-insurance carriers request when binding coverage on improvements inside the state's designated catastrophe area (the 14 first-tier coastal counties plus eastern Harris County east of Highway 146). Requirements vary by carrier — homeowners should confirm what their policy specifically requires.
The hardware standard
Coastal salt air destroys ordinary fasteners in 18 months. Every connection on a coastal pergola has to be T-316 marine-grade stainless steel — not 304, not zinc-plated, not galvanized. The structural aluminum is non-corrosive on its own, but the connections fail first if the wrong grade is specified.
- Fasteners: T-316 marine stainless.
- Base plates: coastal-grade hot-dip galvanized or stainless.
- Anchors: epoxy-set into drilled concrete piers, never expansion-bolted into slab edge.
- Powder coat: AkzoNobel marine-rated finish system on every visible surface.
The process — what inspectors typically look for
A WPI-8 inspection typically happens twice: a foundation review before the slab pour or pier set, and a final review before the structure is released. Inspectors verify foundation geometry (pier diameter, depth, rebar cage, anchor embedment), the base-plate connection, the post-to-beam connection, fastener grade, and the as-installed load path. We provide the engineering documentation homeowners need and can support the inspection process — ask us about documentation for your specific address.
Why the Atrium series is the coastal default
The Atrium is our coastal-grade series. 3.0 mm wall post, dual-wall insulated 220×53 mm blade, sealed gasket louvers, T-316 stainless hardware standard, drilled-pier foundations sized for the bay-area sandy clay profile. Heavy-duty aluminum construction engineered for Gulf Coast conditions — engineering documentation on request for your specific address. The dual-wall blade also gives you a meaningful heat margin during the long bay-summer afternoons — a single-skin blade in coastal humidity is a poor product fit.
Coastal project? Start with a site review.
We provide engineering documentation for your specific address and support the coastal inspection process end-to-end.