CALIFORNIA · SANTA CLARA COUNTY

San Jose sits in a wind-sheltered Silicon Valley basin, where the fault—not the gust—drives the design

Ringed by the Santa Cruz Mountains and the Diablo Range, the South Bay floor sees modest wind while seismic loads run the show. CBC Title 24 points you to ASCE 7-22.

95–105MPH WIND RANGE · RISK II · VARIES BY SITE
Santa ClaraCOUNTY JURISDICTION
ASCE 7-22VIA CBC TITLE 24
BTYPICAL EXPOSURE · URBAN

The orange seam marks what really governs here: active Bay Area faults.

SOUTH BAY WIND CLIMATE

Why the gusts stay gentle on the valley floor

No hurricanes, near-zero tornado history, and a topographic bowl that bleeds energy out of incoming storms before they reach the Silicon Valley grid.

Hills break the flow

The Santa Cruz Mountains and Diablo Range shelter the basin, so the design range stays a modest 95–105 mph for Risk II — site-specific, never one fixed mph.

95–105 MPH

Built-up terrain = Exposure B

Dense downtown, suburban tracts, and tree cover across Willow Glen, Almaden, and Berryessa put nearly all sites in Exposure Category B.

EXPOSURE B

Bayfront edges shift to C

Only the open salt-pond and waterfront strips along south San Francisco Bay step up to Exposure C. Coastal Exposure D does not apply inland.

C AT BAY EDGE

The South Bay reality: seismic leads, wind follows

With the San Andreas, Hayward, and Calaveras faults framing the county, the lateral system, foundations, and connections are almost always sized by earthquake demand. Wind still has the final word on lightweight pieces — roof panels, glazing, and rooftop equipment — where component & cladding pressures can spike well above the main-frame loads.

SANTA CLARA COUNTY · COMPLIANCE CHECKLIST

What a San Jose permit set actually needs to clear plan check

Six pieces every reviewer at the City of San Jose Building Division expects to see for wind, even on a seismic-driven job.

Code basis on the cover

State California Building Code (Title 24) adopting ASCE 7-22 as the wind standard.

CBC · ASCE 7-22

Site wind speed

Pull V from the ASCE 7 hazard tool for the exact address — expect the 95–105 mph band for Risk II.

VARIES BY SITE

Exposure call

Document Exposure B for built-up sites; justify C only near open bay frontage.

B (TYPICAL)

Risk category

Set I–IV per ASCE 7-22 Table 1.5-1; schools, hospitals, and data centers read a higher-speed map.

TABLE 1.5-1

C&C pressures

Run component & cladding for glazing, parapets, roof panels, and equipment — the loads that govern here.

C&C CRITICAL

California PE / SE seal

Commercial structural calcs need a CA-licensed CE or SE seal for permit approval.

SEALED CALCS

INLAND VALLEY VS OPEN COAST

How the South Bay basin reads differently from the California shoreline

Same statewide code, very different wind environment once you leave the sheltered valley floor.

FactorSan Jose — inland valleyCalifornia open coast
Design wind range95–105 mph (varies by site)110–130 mph
Typical exposureB (urban / suburban)C or D (open / coastal)
Wind risk levelLow — hill-shelteredModerate
Governing loadSeismic governsSeismic governs, wind more significant
Salt-spray corrosionNot applicableProtection required
Building codeCBC Title 24CBC Title 24

RUN THE NUMBERS

Get a San Jose-ready wind calculation in minutes

Drop in a Santa Clara County address and the calculator pulls the site wind speed, sets Exposure B, applies your Risk Category, and returns PE-ready MWFRS and C&C pressures for permit submission.