What Renton Homes Need From a Replacement Window
Renton sits in IECC climate zone 4C, which sets the energy-performance bar for any window installed here. Below that, a short list of Renton's longest-licensed window contractors can turn a spec into an actual installed window.
Licenses checked · Washington State Department of Labor & Industries
4CIECC climate zone · ENERGY STAR Northern zone
Renton's climate zone, in plain terms
Moisture and glass performance are handled by different parts of a window's spec sheet, and a Renton 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 1.3 mi away.
What FEMA's risk data says about Renton
King County's hail risk sits at Very Low and its wildfire risk at Relatively Low, according to FEMA's National Risk Index.
Hail risk matters for glass and screen durability in Renton; 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 Renton installer before you settle on a product line.
- Strong wind
- Very Low
- Winter weather
- Relatively High
Data: FEMA, National Risk Index for Natural Hazards - County-level table, v1.20 (v1.20, December 2025).
Guides to finish before Renton 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.
Renton's longest-licensed window installers
Oldest license first, newest last, pulled directly from the state's file. This list isn't for sale.
- Metro Glass CO INCVerify license
- Sound Window & Door INCVerify license
- U Factor Window & Door SalesVerify license
- Badger's Gutter/Window CLNGVerify license
- Advanced Tint LLCVerify license
- NW Window & GutterVerify license
- Cecily Westall GlassVerify license
- Acinstalls LLCVerify license
- Savage Securities INCVerify license