Window Climate Specs for Simi Valley, CA

Simi Valley sits in IECC climate zone 3C, which sets the energy-performance bar for any window installed here. Below that, a short list of Simi Valley's longest-licensed window contractors can turn a spec into an actual installed window.

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

3CIECC climate zone · ENERGY STAR South-Central zone

Simi Valley's climate zone, in plain terms

Ventura County's normal precipitation runs about 17.4 inches a year, with 0.0 inches of snow, which is a separate question from energy performance but still shapes which window details matter in Simi Valley.

Moisture and glass performance are handled by different parts of a window's spec sheet, and a Simi Valley buyer benefits from checking both instead of assuming one implies the other.

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 9.6 mi away.

What FEMA's risk data says about Simi Valley

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 Simi Valley home.

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

Strong wind: Relatively Low
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 Simi Valley 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.

Simi Valley's longest-licensed window installers

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

I M G Glass & MirrorWindow and glass contractor · licensed 43 years · 93065Verify license
Nu-Star Glass & MirrorWindow and glass contractor · licensed 36 years · 93065Verify license
Lockhart Construction & DesignWindow and glass contractor · licensed 33 years · 93065Verify license
Modern Shower DoorWindow and glass contractor · licensed 33 years · 93065Verify license
Community Glass & Mirror CorpWindow and glass contractor · licensed 32 years · 93065Verify license
Preferred Glass And WindowsWindow and glass contractor · licensed 30 years · 93065Verify license
All Roof & Window SystemsWindow and glass contractor · licensed 28 years · 93065Verify license
Paradise Glass RestorationWindow and glass contractor · licensed 27 years · 93065Verify license
Bucks Look N GlassWindow and glass contractor · licensed 27 years · 93065Verify license
Apollo Glazing Contractors INCWindow and glass contractor · licensed 26 years · 93065Verify license
Simi Valley Glass And MirrorWindow and glass contractor · licensed 25 years · 93063Verify license
C G S Custom Glass SpecialistsWindow and glass contractor · licensed 25 years · 93063Verify license

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