Florida Wind Load Calculator: ASCE 7-22, FBC 2023 & HVHZ

Results basis

Show wind loads as ASCE §2.3.1 · §2.4.1

Applies to every pressure, force and moment shown, including the diagrams and PDF. Velocity pressures q_z/q_h and the calc log stay at strength level. Product approvals (NOA / FL#) are usually rated in ASD.

1 · Site

Ultimate design wind speed V ASCE §26.5.1 · FBC §1609.3

mph

Look up V for the site and its Risk Category in the ASCE 7 Hazard Tool or FBC Figures 1609.3(1)–(4), and confirm it with the building department.

Risk Category FBC Table 1604.5 · ASCE Table 1.5-1

Recorded in the report. Use the wind speed V for this Risk Category.

High-Velocity Hurricane Zone FBC §202 · §1620

Glazed openings are impact-protected / impact-rated ASCE §26.12.3 · FBC §1609.1.2 Within 1 mi of a mean high-water line with Exposure D upwind ASCE §26.12.3.1

2 · Wind parameters

Exposure category ASCE §26.7

K_zt §26.8

K_d Tbl 26.6-1

K_e Tbl 26.9-1

K_zt = 1.0 unless the site is on an isolated hill, ridge or escarpment (§26.8.1); rare in Florida, but check bluffs and dunes. K_d = 0.85 for building MWFRS and C&C. In ASCE 7-22, K_d sits in the pressure equations, not in q_z. K_e = 1.0 is always permitted, and at Florida elevations it is ≈ 1.0.

Ground elevation above sea level z_e Tbl 26.9-1

Enclosure classification ASCE §26.12 · Tbl 26.13-1

3 · Building

Length L ∥ ridge

Width W ⊥ ridge

Mean roof height h ASCE §26.2

For θ ≤ 10° ASCE uses the eave height as h (§26.2), and the calculator applies this automatically.

Roof type Fig. 27.3-1

Roof slope θ

Parapet height above roof (0 = none) §27.3.4 · §30.6

Number of stories story forces

Stories are taken as equal height (eave height ÷ number of stories).

Regular-shaped building with no unusual geometry or response (Directional Procedure limits) §26.2 · §27.1.2–27.1.3

4 · Gust effect & rigidity

Gust effect factor G ASCE §26.11

G (user value)

Approx. natural frequency n_a §26.11.3

n₁ (Hz)

5 · Components & cladding

EWA walls §26.2

ft²

EWA roof §26.2

ft²

Effective wind area = span × tributary width, where the width need not be less than span/3 (§26.2). Use the smallest element you are designing, such as a fastener, panel or joist.

Flat roofs: design Zone 1′ with Zone 1 values (conservative) Fig. 30.3-2A

How the Florida wind load calculator works

This free calculator determines design wind pressures for buildings in Florida using ASCE 7-22 and the Florida Building Code, 8th Edition (2023). Enter the ultimate design wind speed V for the site and its Risk Category, from the ASCE 7 Hazard Tool or the FBC wind maps. Then enter the exposure category, enclosure classification, building dimensions, roof type and slope. All calculations run in your browser.

What it calculates

Velocity pressure q_z = 0.00256K_zK_ztK_eV² at each height, and q_h at the mean roof height
Main wind force resisting system (MWFRS) pressures by the Directional Procedure of Chapter 27 for windward, leeward and side walls and the roof, with +GC_pi and −GC_pi cases
Story forces, story shears and overturning moments in both directions, with the 16 psf minimum load check
Components and cladding (C&C) pressures from Chapter 30 for wall Zones 4 and 5 and roof Zones 1, 2 and 3 at your effective wind area, plus parapets
Wind-borne debris region and HVHZ flags, with results at strength level (LRFD, 1.0W) or ASD (0.6W)

Florida and the HVHZ

Miami-Dade and Broward counties are in the High-Velocity Hurricane Zone (HVHZ). There, the Florida Building Code adds requirements such as impact-resistant openings and product approval for envelope components, and the calculator lists these items with the results when you mark the site as HVHZ. Use the wind speed the FBC and your building department require for the site.

Assumptions and limitations

Rigid buildings only. Flexible buildings with a natural frequency below 1 Hz need the gust effect factor G_f of §26.11.5.
Enclosed, partially enclosed and partially open buildings. Open buildings, roof overhangs, rooftop equipment and the Envelope Procedure are not included.
MWFRS Load Case 1 only. The torsional and quartering load cases of Figure 27.3-8 are not generated.
Every coefficient is listed on the Verify tab with its source and confidence level. Some sloped-roof C&C values are placeholders to confirm against ASCE 7-22.

Frequently asked questions

Is Kd included in the velocity pressure?

No. ASCE 7-22 moved the directionality factor Kd out of the velocity pressure equation and into the pressure equations, so qz = 0.00256 Kz Kzt Ke V² and Kd appears when pressures are calculated.

Are the wind pressures ASD or LRFD?

ASCE 7-22 wind loads are strength level, which is what the calculator shows by default for LRFD. Choose ASD (0.6W) under Results basis to see ASD pressures, the basis most product approvals use.

What effective wind area should I use for components and cladding?

Use the span times the tributary width of the element you are designing, where the width need not be less than one-third of the span. Smaller areas, such as fasteners and panels, give higher pressures.

Can I check the calculations?

Yes. The Calc log tab shows every formula with values substituted, the Tests tab runs hand-calculation cases, and the Verify list tab shows every code coefficient the calculator uses.

Related calculators

For educational and preliminary design purposes only. Always verify results with a licensed PE.