Codes & permitting · 5 min read
What is a Wind-Borne Debris Region (WBDR)? A Florida homeowner's guide
Plain-English explanation of the Wind-Borne Debris Region (WBDR) under the Florida Building Code — what it is, where it applies, and what it actually requires of your home's openings.
What is a Wind-Borne Debris Region?
A Wind-Borne Debris Region (WBDR) is an area defined by the Florida Building Code and ASCE 7 where the design wind speed is high enough that flying debris during a hurricane is treated as a near-certainty. In any WBDR, every glazed opening in a habitable building — windows, glass doors, skylights, and the garage door — must either be impact-rated or be protected by an impact-rated covering (shutter or panel). If you've ever wondered why a contractor told you that you 'can't get a permit' without shutters or impact glass, this is almost always the reason.
Where does the WBDR apply in Florida?
Two broad zones. First, anywhere within one mile of the coast where the basic wind speed is 130 mph or greater — which covers essentially the entire Florida coastline. Second, anywhere with a basic wind speed of 140 mph or greater, regardless of distance from the coast — this picks up much of South Florida inland. The High-Velocity Hurricane Zone (HVHZ) in Miami-Dade and Broward is a stricter subset of the WBDR with additional product approval requirements (Miami-Dade NOAs). Practical implication: nearly every coastal Florida home and most of South Florida is in the WBDR, even if it isn't in HVHZ.
What does being in a WBDR actually require?
Three things. (1) Every glazed opening must be protected to the design pressure of the building. (2) The protection must come from a product with a current Florida Product Approval or, in HVHZ, a Miami-Dade NOA. (3) The product must be installed per the manufacturer's tested instructions — wrong anchors or wrong substrate voids the approval and the permit. Garage doors are the most commonly overlooked opening: an unrated garage door in the WBDR will fail the permit inspection on a window project, even if the windows themselves are perfect.
Is my house in the WBDR?
Your local building department can tell you definitively in two minutes. Most Florida counties publish a wind-speed map you can search by address. If you're within roughly a mile of the Atlantic, the Gulf, Tampa Bay, Charlotte Harbor, or the major bays in the Panhandle, assume yes until told otherwise. Inland Central Florida is a mix — Orlando proper is generally not in the WBDR, but the 140-mph contour pulls in parts of the metro depending on the parcel. When in doubt, ask the building department in writing.
What if my house was built before the WBDR rules existed?
Older homes are grandfathered for what was permitted when they were built — you don't have to retrofit unprompted. But any new permit pulled on a glazed opening (window replacement, new door, garage door swap) generally has to meet current code, including opening protection if you're in the WBDR. That's why a 'simple window swap' on a 1980s coastal home can balloon into a project that also requires upgrading the garage door. Our pre-2002 Central Florida guide walks through the older-stock realities; the same logic applies to coastal homes statewide.
How does the WBDR connect to insurance?
Insurers love opening protection because it's the biggest single line on the OIR-B1-1802 wind mitigation form — full impact-rated protection on every opening commonly cuts the wind portion of a premium 25–45%. If you're in the WBDR and your home already meets code, you should be claiming that credit. See the wind mitigation & insurance credits guide for what the inspector checks and how to make the credit stick at renewal.
Next steps if you're in the WBDR
Confirm with your building department whether your address is in the WBDR; pull your existing permits and product approvals together in one folder; book a wind mit inspection if you haven't in five years; and when you're ready to quote new windows, shutters, or a garage door, talk to contractors who routinely permit work in your specific jurisdiction.