Riverside, CA: Climate Zone, Risk and Window Requirements
ENERGY STAR groups Riverside County into its South-Central zone, which is the U-factor and SHGC target worth checking against any quote you get in Riverside. The longest-licensed window contractors based in Riverside are listed below the climate data.
Licenses checked · California Contractors State License Board
3BIECC climate zone · ENERGY STAR South-Central zone
What zone 3B means for a Riverside window
Riverside-San Bernardino-Ontario, CA runs a January average near 56°F and climbs to about 80°F by July, a swing that adds up to roughly 1,258 heating degree days most winters, with 1,977 on the summer cooling side of the ledger.
That load is the actual argument for paying up for a better U-factor in Riverside, separate from anything a brochure claims.
Zone 3B's requirement is the floor; Riverside'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 0.9 mi away.
Storm and weather risk around Riverside
Riverside County's hail risk sits at Relatively Moderate and its wildfire risk at Very High, according to FEMA's National Risk Index.
Hail risk matters for glass and screen durability in Riverside; wildfire risk matters more for the frame material and nearby vegetation than for the glass itself.
Either way, it's a reasonable question to bring to a Riverside installer before you settle on a product line.
- Hurricane
- Very Low
- Strong wind
- Relatively Moderate
- Winter weather
- Relatively Moderate
Data: FEMA, National Risk Index for Natural Hazards - County-level table, v1.20 (v1.20, December 2025).
Guides to finish before Riverside 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 Riverside
Oldest license first, newest last, pulled directly from the state's file. This list isn't for sale.
- Aluminex IncorporatedVerify license
- Roy E Whitehead INCVerify license
- Riverside Glass & MirrorVerify license
- All About Glass And Screens INCVerify license
- Schwartz ConstructionVerify license
- Precision Glass & MirrorVerify license
- Lakeshore Glass And Metal INCVerify license
- Fred's Glass & Mirror INCVerify license
- M S B ConstructionVerify license
- Prime BuildersVerify license
- Majestic WindowsVerify license
- M - Tech Glass INCVerify license