The High-Velocity Hurricane Zone: What FBC Chapter 16 and Miami-Dade Product Approval Mean for Your Project

The Short Version

The high velocity hurricane zone, or HVHZ, is the part of the Florida Building Code that applies only in Miami-Dade and Broward counties. It is the strictest wind standard in the state. Inside it, buildings are designed to wind loads under Section 1620 of Chapter 16, the building envelope has to resist windborne debris under Section 1626, and the windows, doors, shutters, roofing and other envelope products must carry a product approval that is valid for HVHZ use, most often a Miami-Dade Notice of Acceptance, or NOA.

For architects and contractors, the practical effect is that the structural design and the product approvals have to match each other. The engineer establishes the design pressures for every part of the building, the drawings show them, and each product specified or submitted has to be approved for at least those pressures, in that size, installed the way its approval describes. When those three things line up, permits and inspections move. When they do not, the job stops at plan review or at the final inspection, and the fix is usually expensive. The structural design and analysis work behind that match is where most HVHZ problems are prevented.

What the High Velocity Hurricane Zone Is

The HVHZ is a defined area, not a wind speed contour. The Florida Building Code applies its HVHZ provisions to Miami-Dade and Broward counties, and to every address within them, from the coast to the edge of the Everglades. Palm Beach County and the rest of the state are outside it, even where their design wind speeds are high. The provisions grew out of the South Florida Building Code, which the two counties strengthened after Hurricane Andrew in 1992, and they were carried into the statewide Florida Building Code when it took effect in 2002.

The HVHZ rules are not a single chapter. They are sections placed throughout the code, and a project in Miami-Dade or Broward has to meet the ones that apply to its structure and envelope. The main places they appear are these.

• Chapter 15, where the HVHZ roofing sections govern roof systems, underlayments, attachment and roofing application standards.
• Chapter 16, where Section 1620 sets HVHZ wind loads and Section 1626 sets the impact tests for windborne debris.
• Chapters 19, 21, 22 and 23, which carry HVHZ sections for concrete, masonry, steel and wood construction.
• The Test Protocols for HVHZ, a separate volume of the code containing the Testing Application Standards, such as TAS 201, TAS 202 and TAS 203, that products are tested against.
  

Section 1620 requires buildings and structures in the HVHZ, and every portion of them, to be designed and constructed to Chapters 26 through 31 of ASCE 7, the wind load chapters of the standard. The 8th Edition of the Florida Building Code, in effect since December 31, 2023, correlates its wind criteria with ASCE 7-22. One HVHZ rule has a large effect on the numbers: every building is treated as Exposure Category C unless Exposure D applies, so a site in a dense neighborhood does not get the lower pressures a suburban Exposure B site would get elsewhere.

Design wind speeds in the HVHZ are among the highest in the country. Miami-Dade County describes its product approvals as meeting HVHZ codes designed for winds up to 175 miles per hour, measured as a three-second gust, for typical buildings, and higher risk categories use higher values again. The speed for a specific project comes from the adopted map for its location and its risk category, and it drives both the main wind force resisting system and the components and cladding pressures that products are later matched against.

FBC Chapter 16 in the HVHZ

Section 1620: Wind Loads

Impact Tests for Windborne Debris

Section 1626 is why HVHZ envelope products are different. Assemblies used up to and including 30 feet above grade must pass the large missile impact test, run on three specimens under TAS 201 and TAS 203. The large missile is a 9 pound piece of nominal 2 by 4 lumber, fired at the specimen at 50 feet per second, and specimens that survive the impacts are then put through cyclic pressure loading. Above 30 feet, the small missile test applies, using small steel balls under TAS 201, except that Risk Category IV essential facilities follow the large missile test at every height.

Two details in Section 1626 matter on site. The test specimen is the entire assembled unit, including its frame and anchorage, with fasteners identical in size and spacing to those used in the field, so the installation is part of what was approved. And where shutters or other external devices protect glazing, they must resist the large missile without deforming far enough to touch the glass they protect. The code also lists assemblies deemed to comply without testing, such as 8 inch concrete masonry walls built to the HVHZ masonry provisions.

Miami-Dade Product Control and the NOA

A Notice of Acceptance is issued by Miami-Dade County's Product Control Section, part of the Board and Code Administration Division. The county states that all products making up a building envelope, such as doors, shutters, windows, prefabricated buildings and truss plates, require an approval before they can be used in construction in Miami-Dade. NOAs also cover items such as railings, screen enclosures, awnings and precast elements, and manufacturers holding one must maintain a quality assurance program.

An NOA is specific, and that is its value. It lists the tested configurations, the maximum sizes, the approved positive and negative design pressures, the substrates the product may be anchored into, the anchor type and spacing, and an expiration date. The statewide alternative is a Florida Product Approval issued through the Florida Building Commission. It can be used in Miami-Dade and Broward only where it lists the product as approved for use in the HVHZ, and a statewide approval that does not say so is not enough.

What It Means for Architects and Contractors

For the architect, the HVHZ changes what the drawings need to show. Building departments in Miami-Dade and Broward review product approvals against the design pressures on the permit set, so those pressures have to be there, zone by zone and opening by opening, not left for the window supplier to work out. Corner and edge zones of walls and roofs carry higher pressures than field zones, and a tall building has higher pressures at its upper floors, so one pressure value for the whole elevation is rarely right.

For the contractor, the product approval becomes a set of instructions. The unit that arrives on site has to be the tested unit, in a size the approval covers, fixed into the substrate the approval lists with the anchors and spacing it shows. Inspectors compare the installation with the approval, and a mismatch found at the final inspection is fixed by removing and reinstalling work that is already finished. That is the reason to resolve product selection during design, not during procurement. It matters just as much on existing buildings, where repair and replacement work after a milestone inspection or a recertification has to meet the same HVHZ approvals as new work.

How the Design and the Approvals Fit Together

On a well-run HVHZ project the structural engineering and the product approvals are coordinated in a fixed order, so each step has what it needs from the one before. The sequence below is how that usually works.

• Set the design criteria: risk category, design wind speed for the location, Exposure C or D, and the enclosure classification of the building.
• Calculate the main wind force resisting system loads and the components and cladding pressures for each zone of the walls and roof, and show those pressures on the drawings.
• Specify envelope products whose HVHZ approvals meet or exceed those pressures at the sizes shown, and confirm each approval is current.
• Detail the openings and substrates to match the approvals, including bucks, sills, mullions and embedment, and design any structure the approval relies on, such as the wall or beam receiving the anchors.
• Review the shop drawings and product submittals against the approvals and the design pressures before anything is ordered.
• Verify the installation in the field against the approved anchorage and configuration before the work is closed up.
  

The same order applies to roofs. A roof system approval is tied to the deck it was tested on and to its attachment pattern, so the deck and the uplift pressures in each roof zone have to be settled before the roofing approval can be confirmed. Independent structural plan review before permit submission can catch gaps in that sequence while they are still inexpensive to fix.

Mistakes That Stall HVHZ Permits and Inspections

Most HVHZ problems are not about whether a building can be designed for the loads. They come from gaps between the design, the approvals and the installation. These are the ones that come up most often.

• Drawings with no components and cladding pressures, which leaves the reviewer nothing to check the product approvals against.
• An expired approval, or one that has been superseded or revised, submitted from an old project file.
• A product used larger than its approval allows, or at a location whose design pressure is higher than its approved rating.
• Anchorage into a substrate the approval does not list, such as wood bucks where the approval covers only concrete or masonry.
• Mulled window assemblies installed without an approval covering the mullion itself.
• Roofing installed over a deck, or with a fastening pattern, different from the one the roof system approval was tested on.
  

The 9th Edition Change on December 31, 2026

The Florida Building Code updates every three years, and the next change is close. Miami-Dade's Product Control Section has announced that the 9th Edition of the code becomes effective on December 31, 2026, and that changes to the HVHZ sections of Chapter 15 and to the HVHZ test protocols will affect some current NOAs for roofing underlayments. Other product categories may see revisions as manufacturers update their approvals to the new edition.

For projects in design now, the practical step is to confirm with the building department which edition will govern the permit, based on when the application will be submitted, and to check the status of each specified approval shortly before submission rather than relying on the one in the specification. A roofing underlayment approval that was valid during design may need replacing if the permit falls under the 9th Edition.

How M&P Consulting Engineers Approaches HVHZ Design

Jonnatan R. Mendez, PE, SI, has more than 20 years of structural engineering in South Florida, beginning with structural design at Brindley Pieters & Associates in Miami and later as chief structural engineer at DLG Engineering. He is a Florida Threshold Building Special Inspector with qualified plans examiner experience under the Florida Building Code, and his work covers concrete, masonry, steel, aluminum, wood and post-tensioned systems, with wind and hurricane load analysis under ASCE 7.

Our HVHZ designs carry the design pressures on the drawings and are coordinated with the product approvals the architect and contractor intend to use, so the permit set, the submittals and the installation all point at the same numbers. We work from new construction and additions through repairs and retrofits of existing buildings in Miami-Dade and Broward, and our structural design projects range from new single family homes to repairs of fire-damaged high-rise condominiums.

Our forensic work informs the design side as well. Investigating how buildings perform in real storms, including the wind damage patterns described in our guide to hurricane damage claims, shows which connections and envelope details fail first, and those are the details we pay most attention to when the building is still on paper.

Common Questions About the High Velocity Hurricane Zone

Designing a Project in Miami-Dade or Broward?

M&P Consulting Engineers provides signed and sealed structural design, wind load analysis and HVHZ coordination for architects, contractors and owners across South Florida. Call 866-531-7621 early in design, while the pressures and the product approvals can still be matched on paper.

Sources

Florida Building Code, Building, 8th Edition (2023), Chapter 16, Sections 1620 (High-Velocity Hurricane Zones, Wind Loads) and 1626 (High-Velocity Hurricane Zones, Impact Tests for Wind-Borne Debris).

Florida Building Code, Test Protocols for High-Velocity Hurricane Zones, 8th Edition (2023): TAS 201, TAS 202, TAS 203.

Florida Building Commission, Wind Loads: Impacts From ASCE 7-22 (fact sheet, June 2024).

Miami-Dade County Board and Code Administration Division, Product Control Section: Ensuring Strict Standards for Construction Materials, and Product Approval Notices. Checked 24 September 2026.

ASCE/SEI 7-22, Minimum Design Loads and Associated Criteria for Buildings and Other Structures, Chapters 26 to 31.