The Wind-Load Checker, County In, Verdict Out
Two American programs attach real paperwork to a garage door install or repair: the Texas TDI windstorm inspection program — WPI-8 certificates in 14 first-tier seacoast counties plus part of Harris — and the Florida High-Velocity Hurricane Zone in Miami-Dade and Broward. The checker below answers for any county; everywhere else, the door’s wind-load rating still has to match the local code map.
// THE NUMBERS UP FRONT
Does a windstorm rule bind your garage door?
Two US programs put paperwork on a garage door install or repair: the Texas TDI windstorm inspection program (WPI-8 certificates in the first-tier seacoast counties) and the Florida High-Velocity Hurricane Zone (Miami-Dade and Broward). Pick a state and county — the verdict names the certificate, or clears you to the ordinary permit path.
// THE VERDICT
Pick a county
Texas has 14 first-tier seacoast counties in the TDI program, plus the Harris County carve-out east of State Highway 146.
Which Texas counties are in the TDI program?
The 14 first-tier seacoast counties, plus the carve-out — the exact set the checker tests against, published as data on the Wind-Load Index.
| Counties | Status |
|---|---|
| Aransas · Brazoria · Calhoun · Cameron · Chambers · Galveston · Jefferson | first-tier seacoast — WPI-8 territory |
| Kenedy · Kleberg · Matagorda · Nueces · Refugio · San Patricio · Willacy | first-tier seacoast — WPI-8 territory |
| Harris, east of State Highway 146 (Seabrook, La Porte, parts of Baytown) | in the program — the carve-out |
| Harris, west of SH 146, and every other Texas county | standard inland rules |
What the verdict means in practice
WPI-8 territory
Door work that counts as an improvement wants the windstorm inspection path from the start: compliant product, engineering on file, inspection scheduled, certificate kept with the insurance papers. Retrofitting the paperwork after the fact ranges from painful to impossible.
HVHZ territory
Product approval is the gate: current NOA or HVHZ-listed Florida Product Approval, checked at permit time. The county portals publish approval databases — verify the number before signing, not after delivery.
Wind-borne debris regions (FL beyond the HVHZ)
Opening protection requirements follow the local wind-speed map even where the HVHZ label does not apply. The county permit office answer is the binding one — and it is a phone call, not a project.
Everywhere else
The adopted code’s wind provisions still set a required rating for the door — and a wind-rated door or a retrofit bracing kit remains one of the highest-return structural upgrades a storm-prone house can buy voluntarily.
Wind rules — the questions that matter
What is a WPI-8 and when does a garage door need one?
The WPI-8 is the Texas windstorm inspection certificate: documentary proof that an improvement — a garage door very much included — was inspected for windstorm code compliance. It matters in the TDI program’s 14 first-tier seacoast counties (plus Harris County east of State Highway 146), where TWIA windstorm insurance requires WPI-8 documentation for covered improvements. Practically: replace a garage door in Galveston without the inspection trail and the windstorm policy on the house has a documentation hole exactly where hurricanes aim.
What does the Florida HVHZ require of a garage door?
The High-Velocity Hurricane Zone — Miami-Dade and Broward counties only — is the strictest opening-protection regime in the country: 170–180 mph ultimate design wind speeds, minimum DP-30 design pressure, and mandatory large-missile impact rating. Products need a current Miami-Dade NOA or a Florida Product Approval with HVHZ listing, and the details bite: Broward-only approvals are not valid in Miami-Dade, and NOAs carry expiration dates that must be current at permit time.
My county is in neither program — can I ignore wind ratings?
No — the absence of a certificate program is not the absence of a requirement. Nearly every US jurisdiction enforces the wind-load provisions of its adopted building code, which map design wind speeds to required door pressure ratings; coastal and plains jurisdictions often adopt stricter local maps. What changes outside TDI and HVHZ territory is the paperwork (ordinary permitting, no special certificate), not the physics. The rating label on the door still has to meet the local map, and the permit office holds the map.
Why do garage doors matter so much in windstorm codes?
Because the garage door is usually the largest and weakest opening in the building envelope. When one fails inward during a storm, the house pressurises like a paper bag — internal pressure pushes up on the roof deck and out on the walls, and roof loss follows. That failure chain is documented across decades of post-hurricane engineering surveys, and it is why opening-protection rules treat the biggest opening with the most suspicion, and why a wind-rated door or retrofit bracing kit is cheap insurance far outside any mandated zone.
Does a repair trigger the same rules as a replacement?
The line varies by jurisdiction, but the safe generalisation: like-for-like minor repairs (a panel, a spring, hardware) usually stay under the permit threshold, while full door replacement is an improvement that triggers current-code compliance — including the wind provisions and, in program territory, the inspection trail. Two practical rules: ask the permit office before assuming, and never let a contractor’s "no permit needed" be the only opinion on file when windstorm insurance documentation is at stake.
What should I ask an installer in a wind-rule county?
Four questions, all answerable on the spot by a legitimate outfit. Which design pressure is this door rated for, and where is the label? Which approval covers it here — NOA, Florida Product Approval, or the engineering behind the WPI-8 path? Who files the permit and schedules the inspection — you or me? And will the documentation package (rating label, approval number, inspection certificate) be in my hands at the end? An installer fluent in those answers works these counties weekly; one who waves them off is shopping elsewhere for you.