San Rafael, CA: Climate Zone, Risk and Window Requirements
ENERGY STAR groups Marin County into its South-Central zone, which is the U-factor and SHGC target worth checking against any quote you get in San Rafael. The longest-licensed window contractors based in San Rafael are listed below the climate data.
Licenses checked · California Contractors State License Board
3CIECC climate zone · ENERGY STAR South-Central zone
San Rafael's climate zone, in plain terms
San Rafael falls in IECC climate zone 3C, and ENERGY STAR separately groups Marin County into its South-Central zone for window certification.
Those two numbers, not the brand on the box, set the U-factor and SHGC worth checking on any quote you get in San Rafael.
A San Francisco-Oakland-Fremont, CA contractor who can't name either one on request is worth a second question before you sign.
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 2 mi away.
What FEMA's risk data says about San Rafael
FEMA scores Marin County's winter-weather risk as Very Low and its flood risk as Relatively High.
Winter risk in San Rafael weighs on U-factor and condensation resistance; flood risk weighs more on sill height and drainage detailing than on the glass package.
Treat these as two separate conversations with a San Rafael contractor, not one.
- Strong wind
- Very 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 San Rafael 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.
San Rafael's longest-licensed window installers
Oldest license first, newest last, pulled directly from the state's file. This list isn't for sale.
- Solarium & Skylight SystemsVerify license
- Dotto Glass INCVerify license
- Metropolitan Glass CorporationVerify license
- Window WorxVerify license
- SMF Glass INCVerify license
- North Bay Shower Door INCVerify license
- Leo's Glass Windows And DoorsVerify license