Design Wind Speed Is Not One Number Statewide

The Florida Building Code incorporates ASCE 7 wind speed maps, which assign a design wind speed by geographic location. Coastal areas generally carry higher design wind speeds than inland locations even within the same county, because the maps reflect actual historical and modeled storm exposure. A structure designed for one address in a county is not automatically adequate for a different address closer to open water in the same county — the site-specific design wind speed has to be pulled for the actual parcel, not assumed from the county name.

Exposure Category Changes the Load, Too

Beyond raw wind speed, ASCE 7 assigns an exposure category (most relevantly B, C, or D) based on the surrounding terrain roughness. Open coastal terrain and large open water exposure (Exposure D) or flat open terrain (Exposure C) generate higher effective wind pressures on a structure than a site sheltered by dense surrounding construction (Exposure B), even at the identical design wind speed. Sarasota, Manatee, and Charlotte counties include a wide range of exposure conditions, from open Gulf-front lots to interior, tree-sheltered subdivisions — and the correct exposure category for the specific site materially changes the calculated load.

HVHZ vs. Non-HVHZ: What Actually Applies Here

Florida’s High-Velocity Hurricane Zone (HVHZ) provisions apply specifically to Miami-Dade and Broward counties. Sarasota, Manatee, and Charlotte counties are governed by the Florida Building Code’s standard (non-HVHZ) wind provisions, which use a different testing and product-approval framework than HVHZ. That distinction affects which product approvals and installation methods are applicable — a product tested and approved under HVHZ protocols is not automatically the correct (or most cost-effective) choice outside the HVHZ, and a non-HVHZ product approval is not valid for an HVHZ jurisdiction. We specify products and connection details against the standard that actually governs the installation address.

Uplift vs. Lateral Load

Wind generates both an uplift component (perpendicular to the roof surface, effectively trying to lift the roof off the structure) and a lateral component (pushing the structure horizontally). Open-sided structures like carports and screen enclosures are particularly sensitive to uplift because they lack walls to help resist and redistribute lateral forces the way an enclosed building does. Roof geometry — slope, overhang length, and eave detailing — directly affects how much uplift pressure the roof surface actually experiences, which is why the same footprint can require meaningfully different connection detailing depending on roof design.