FLORIDA · DUVAL COUNTY
Where the St. Johns River meets the First Coast Atlantic wind
Jacksonville sits on Northeast Florida's Atlantic shoulder — hurricane-exposed, river-cut, and well north of the HVHZ. Standard Florida Building Code rules apply here, not Miami-Dade's high-velocity regime.
FIRST COAST GEOGRAPHY
Ocean swell, river bend, and a city that spans both
From the Atlantic beaches to wooded interior tracts, terrain shifts the exposure category across one of the largest cities by land area in the lower 48.
Exposure C — the beaches
Jacksonville Beach, Atlantic Beach, Neptune Beach and Ponte Vedra face open Atlantic flow. Direct ocean exposure pushes the upper 135–140 mph band.
COASTALExposure B — wooded interior
Unlike Miami-Dade's blanket Exposure C, Duval lets inland, built-up and forested tracts west of the river qualify for Exposure B where terrain supports it.
INLANDExposure D — rare beachfront
Reserved for structures directly on the sand with unobstructed open-water fetch for a long distance — a narrow slice of the oceanfront.
SITE-SPECIFICNORTH OF THE LINE
Coastal exposure, but standard FBC — not HVHZ
Jacksonville carries real Atlantic hurricane risk, yet the High-Velocity Hurricane Zone stops far to the south. Duval uses Florida Product Approval, not Miami-Dade NOA.
| Topic | Jacksonville (Duval, NOT HVHZ) | Miami-Dade / Broward (HVHZ) |
|---|---|---|
| Design wind (Risk II) | 130–140 mph | Typically ~170–180 mph |
| Product approval | Florida Product Approval | Miami-Dade NOA |
| Impact testing | Standard FBC provisions | Mandatory TAS protocols |
| Exposure rule | C coastal · B allowed inland | Exposure C effectively mandated |
| Method | ASCE 7-22 per FBC 8th Ed. | ASCE 7-22 + HVHZ overlay |
Why the First Coast reads lower than South Florida
Jacksonville's more northern latitude and the curve of the Atlantic shoreline reduce sustained design velocities versus the Southeast Florida coast. The exact figure still varies by site — beaches near Mayport and the oceanfront sit at the top of the range; inland tracts west of the St. Johns River sit toward the bottom.
RISK CATEGORY · ASCE 7-22 TABLE 1.5-1
Heavier occupancies read a longer-return wind map
Risk category does not multiply your speed — it points you at a different basic wind speed map with a longer mean recurrence interval. Higher category, longer return period, higher load.
| Risk Category | Map (MRI) | Typical Jacksonville Buildings |
|---|---|---|
| I | 300-year | Agricultural, minor storage, low-occupancy structures |
| II | 700-year | Homes, retail, offices — most standard occupancy |
| III | 1,700-year | Schools, assembly over 300, substantial-hazard facilities |
| IV | 3,000-year | Hospitals, fire/police, EOCs, hurricane shelters |
DUVAL COUNTY COMPLIANCE
What a Jacksonville permit set has to carry
Every sealed wind calculation in Duval County hangs on the same four pillars.
Site wind speed
Pull V from the ASCE 7-22 map for the exact address — 130–140 mph for Risk II, set by distance from the coast.
130–140 MPHExposure call
C for oceanfront and open beach terrain; B for built-up, wooded inland blocks — justified with surrounding-roughness notes.
C / BProduct approval
Windows, doors, roofing, cladding and shutters must carry valid Florida Product Approval numbers — verified at the state database.
FL-PAFlorida PE seal
Calculations must be sealed by a Florida-licensed PE or architect, with full ASCE 7-22 methodology plus C&C and MWFRS pressures.
SEALEDOFFICIAL REFERENCES
Verify it at the source
Duval County and state portals for permit, product approval and licensing checks.
Jacksonville Building Inspection
City of Jacksonville Building Inspection Division.
COJ.NETFlorida Building Commission
Search and verify Florida Product Approval numbers.
FL-PA DBFlorida PE Licensing (DBPR)
Confirm engineer and architect licensure status.
DBPRFirst Coast mistakes to dodge
Don't borrow Miami's 175 mph or its NOA path — Jacksonville is standard FBC. Don't force Exposure C on a sheltered inland lot, don't apply HVHZ TAS testing where it isn't required, and don't run an older ASCE edition: FBC 8th Edition mandates ASCE 7-22.
EXPLORE FLORIDA
Compare across the Sunshine State
From the First Coast standard zone down to the South Florida HVHZ.
RUN THE NUMBERS
Get a Jacksonville-compliant wind load calculation
Enter a Duval County address and the calculator applies the 130–140 mph map band, exposure guidance, risk category and full ASCE 7-22 pressures — PE-ready for permit submission.