HVHZ, Wind-Borne Debris Regions, and What Applies in Central Florida
It’s tempting to think of Florida’s wind code as organized by county, but mostly it isn’t. It’s organized by mapped design wind speeds and by distance from large bodies of water. County lines just happen to cross those maps in different places. That’s why two homes in the same county can face different window and door requirements.
Short version: The Florida Building Code has three wind tiers. The High-Velocity Hurricane Zone (HVHZ) is Miami-Dade and Broward counties, with the strictest product rules. The Wind-Borne Debris Region (WBDR) covers areas with a design wind speed of 140 mph or more, plus areas within one mile of the coastal water line where the wind speed is 130 mph or more. In the WBDR, windows and doors need impact-rated glass or shutters. Everywhere else, standard wind design applies. Most of Central Florida falls in the 130 to 139 mph band and outside the WBDR. Large inland lakes are the exception to watch. When the 2023 code first took effect, its wording briefly pulled areas near lakes like Lake Apopka, Lake Conway, and the Butler Chain into the WBDR, until an amendment restored the coastal-only rule. Proposals to change this again were filed for the 9th Edition, which takes effect December 31, 2026, so always check your specific address.
The three tiers
| Tier | Where it applies | What it means for a home |
|---|---|---|
| High-Velocity Hurricane Zone (HVHZ) | Miami-Dade and Broward counties only | The strictest requirements, including HVHZ-specific product testing and approvals |
| Wind-Borne Debris Region (WBDR) | Design wind speed of 140 mph or more, or within 1 mile of the coastal mean high water line where the speed is 130 mph or more | Windows, glass doors, and other openings need impact-rated products or approved shutters |
| Standard wind design | Everywhere else in Florida, including most of Central Florida | The structure, roof, and openings must still be designed for the mapped wind speed, but impact protection isn’t required |
Wind speeds here are “ultimate design wind speeds” for Risk Category II buildings, which includes most homes. Critical buildings like hospitals use higher maps.
The HVHZ is the one tier defined by county. The WBDR follows the mapped wind speed and distance from the water, not county lines. Florida’s long coastline means much of the coastal strip, and large areas of South Florida and the Panhandle, are in the WBDR. Most of the interior is not.
What applies in Central Florida
Inland Central Florida, including most of Orange, Osceola, Seminole, Lake, and Polk counties, falls in the 130 to 139 mph design wind speed band, according to a 2024 University of Florida study for the Florida Building Commission. That’s below the 140 mph statewide WBDR trigger, and these areas are far from the coast, so impact protection generally isn’t required for new homes. New homes here still have to be engineered and built for those wind speeds. That covers roof-to-wall connections, roof sheathing nailing, and window and door pressure ratings. The coastal counties to the east, Volusia and Brevard, have WBDR areas along the coast.
The inland lake question
Florida’s 8th Edition Building Code (2023) adopted the ASCE 7-22 wind standard. That edition dropped the word “coastal” from the one-mile rule, so the WBDR could include land within a mile of any large body of water with open-water exposure, inland lakes included. A University of Florida study for the Florida Building Commission identified Central Florida lakes this could affect, including Lake Apopka, Lake Conway, the Butler Chain of Lakes, Lake Tohopekaliga, Lake Louisa, Lake Minneola, Lake Harris, Lake Eustis, Lake Dora, and Lake Griffin.
A later technical amendment to the 8th Edition restored the coastal-only wording, which took those inland lake areas back out. The question isn’t settled, though:
- The UF study concluded that lakefront neighborhoods face debris risk similar to coastal ones, but recommended a narrower band of about 3,000 feet from the water instead of a full mile.
- Code change proposals for the 9th Edition (2026) would have struck “coastal” again, or replaced the one-mile rule with a simple 130 mph threshold. The 130 mph version would add much more of Central Florida to the WBDR.
If you’re building, replacing windows, or buying near a large lake, ask your local building department which WBDR definition applies to your permit, especially for applications submitted on or after December 31, 2026.
Replacing windows and doors in an existing home
If your home is in the WBDR, replacement windows, exterior doors, garage doors, and skylights generally have to meet current code, which means impact-rated products or approved shutters. The Florida Building Code, Existing Building (Section 707.4) has a limited exception for older one- and two-family homes:
- For homes permitted under codes before the Florida Building Code took effect in 2002, replacements made within any 12-month period don’t need impact protection if they’re designed for the required wind pressure and total no more than 25% of the home’s glazed opening area.
- Go past 25% within 12 months and the replaced openings need impact protection. A phased project can cross that line without you noticing, so track the total.
Building departments apply these rules a little differently, so check with yours before ordering windows. Impact windows and shutters can also earn wind mitigation insurance credits. See 4-point and wind mitigation inspections and the My Safe Florida Home program.
A related roof rule
A similar question comes up with roofs. Under Florida Statute 553.844(5), if an existing roof was built, repaired, or replaced under the 2007 Florida Building Code or later, then even when 25% or more of it is repaired or replaced, only the repaired portion has to meet the current code. Older roofs can still trigger a larger replacement. See Florida roof lifespan and replacement.
The 9th Edition (2026)
The 9th Edition Florida Building Code takes effect December 31, 2026, and applications submitted on or after that date must follow it. Wind-borne debris rules were among the topics under review, as described above. Permits applied for before the effective date are generally reviewed under the 8th Edition. If you’re timing a project around the changeover, confirm the details with your building department rather than relying on contractor marketing about what’s changing. See Florida building permits for how the process works.
How to check your address
- Your building department: the final word on which wind speed and WBDR status apply to your permit.
- ASCE Hazard Tool: the American Society of Civil Engineers’ tool returns ASCE 7 design wind speeds for a specific address. Engineers use it, but Florida’s adopted maps and amendments govern.
- UF GeoPlan Center wind speed maps: the statewide and county-level wind speed line maps and WBDR map prepared for the Florida Building Code.
Frequently Asked Questions
Only Miami-Dade and Broward. It’s the one wind tier defined by county. The rest of Florida’s wind rules follow mapped wind speeds and distance from the water.
Generally not. Most of inland Central Florida is in the 130 to 139 mph band and outside the Wind-Borne Debris Region. Areas near large lakes have been debated, so check your address with the building department.
A mapped design wind speed of 140 mph or more, or a location within one mile of the coastal mean high water line where the wind speed is 130 mph or more. It’s based on location, not county.
In the Wind-Borne Debris Region, generally yes. Homes built before the Florida Building Code took effect can replace up to 25% of their glazed area in a 12-month period without impact protection. Beyond that, the replaced openings need it.
Your local building department has the final word. The ASCE Hazard Tool returns design wind speeds for an address, and the UF GeoPlan Center publishes the wind speed and debris region maps used for the Florida Building Code.
Sources
- Florida Building Commission: Investigation of the Wind-borne Debris Regions in ASCE 7-22, Final Report (University of Florida)
- Florida Building Commission: Wind-borne Debris Regions in ASCE 7-22, Interim Report
- Florida Roofing and Sheet Metal Contractors Association: Where is the Windborne Debris Region? Is it going to change? (2025)
- Florida Building Commission: Replacement window and door exception, FBC Existing Building 707.4 (code development document)
- City of Cape Coral: Residential window and door replacement guidelines
- Florida Statutes, Section 553.844: Windstorm loss mitigation; roofs
- Miami-Dade County: 9th Edition (2026) Florida Building Code effective date notice
- University of Florida GeoPlan Center: Wind speed line maps for the Florida Building Code
- American Society of Civil Engineers: ASCE Hazard Tool
This article is for general informational purposes only and isn’t financial, legal, insurance, or tax advice – for guidance specific to your situation, talk to a licensed professional.