Fullerton, CA: Climate Zone, Risk and Window Requirements

Local risk and climate data for Fullerton, CA are below, translated into plain terms for a window buyer rather than left as raw codes. Use it to check a proposed spec before you sign, not just to browse.

Licenses checked September 30, 2026 · California Contractors State License Board

3BIECC climate zone · ENERGY STAR South-Central zone

What zone 3B means for a Fullerton window

Los Angeles-Long Beach-Anaheim, CA runs a January average near 58°F and climbs to about 75°F by July, a swing that adds up to roughly 1,051 heating degree days most winters, with 1,507 on the summer cooling side of the ledger.

That load is the actual argument for paying up for a better U-factor in Fullerton, separate from anything a brochure claims.

Zone 3B's requirement is the floor; Fullerton's specific load is what tells you whether beating that floor is worth the extra cost.

Data: U.S. EPA / DOE, ENERGY STAR, ENERGY STAR Version 7.0 Climate Zones by County/ZIP (Windows, Doors, and Skylights) (V7.0); Pacific Northwest National Laboratory (DOE Building America), Guide to Determining Climate Zone by County: Building America and IECC 2021 Updates (PNNL-33270) (2021 IECC), from the nearest NOAA station 3.1 mi away.

Storm and weather risk around Fullerton

Neither rating changes a window's energy label, but both are exactly what impact-resistance and design-pressure ratings are built to answer for a Fullerton home.

Ask specifically about design pressure and impact rating for Fullerton, not just energy performance, if either risk rating comes back on the high side.

Strong wind: Relatively Moderate
Winter weather: Very Low

Data: FEMA, National Risk Index for Natural Hazards - County-level table, v1.20 (v1.20, December 2025).

Guides to finish before Fullerton window bids come in

How to Read an NFRC Window Label Four numbers on one sticker decide most of a window's real-world performance. Here's what each one means.
ENERGY STAR Window Criteria by Climate Zone ENERGY STAR splits the country into four zones, each with its own numbers. Here they are, and why the Northern zone works backward from the other three.
Impact Windows vs. Shutters in Florida's Hurricane Zones Florida gives homeowners two paths to a protected opening. Here's how each one is tested, and where the HVHZ raises the bar further.

Window installers with the longest license records in Fullerton

Oldest license first, newest last, pulled directly from the state's file. This list isn't for sale.

Fullerton Glass COWindow and glass contractor · licensed 38 years · 92831Verify license
A A A Glass Tech U S AWindow and glass contractor · licensed 29 years · 92631Verify license
S P S Construction ServicesWindow and glass contractor · licensed 21 years · 92831Verify license
Rainbow Glazing INCWindow and glass contractor · licensed 21 years · 92831Verify license
Richelieu Glass COWindow and glass contractor · licensed 19 years · 92835Verify license
T - Glass INCWindow and glass contractor · licensed 16 years · 92831Verify license
Onyx Glass & AluminumWindow and glass contractor · licensed 5 years · 92833Verify license
Interior Glass CreationsWindow and glass contractor · licensed 4 years · 92833Verify license
Orange Coast Windows INCWindow and glass contractor · licensed 3 years · 92831Verify license
Golden Glass INCWindow and glass contractor · licensed under a year · 92831Verify license
Quality Glass O C CorpWindow and glass contractor · licensed under a year · 92832Verify license
Top Tier Windows & Glass DoorsWindow and glass contractor · licensed under a year · 92833Verify license

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