Portland, OR: Climate Zone, Risk and Window Requirements

Portland sits in IECC climate zone 4C, which sets the energy-performance bar for any window installed here. Below that, a short list of Portland's longest-licensed window contractors can turn a spec into an actual installed window.

Licenses checked September 30, 2026 · Oregon Construction Contractors Board

4CIECC climate zone · ENERGY STAR Northern zone

What zone 4C means for a Portland window

Multnomah County's normal precipitation runs about 44.1 inches a year, with 3.6 inches of snow, which is a separate question from energy performance but still shapes which window details matter in Portland.

Moisture and glass performance are handled by different parts of a window's spec sheet, and a Portland 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 2.3 mi away.

Storm and weather risk around Portland

Multnomah 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 Portland; 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 Portland installer before you settle on a product line.

Strong wind: Relatively Moderate
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 Portland 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 Portland

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

All Season Windows LLCWindow and glass contractor · licensed 22 years · 97228Verify license
Glacier Window & Door INCWindow and glass contractor · licensed 18 years · 97293Verify license
Viridian Window Restoration LLCWindow and glass contractor · licensed 16 years · 97212Verify license
Rose City Windows & Doors LLCWindow and glass contractor · licensed 16 years · 97210Verify license
Window Finishing INCWindow and glass contractor · licensed 15 years · 97206Verify license
Bridgetown Window & Door INCWindow and glass contractor · licensed 13 years · 97220Verify license
Dr Windows And Glass LLCWindow and glass contractor · licensed 10 years · 97218Verify license
Brightside Windows LLCWindow and glass contractor · licensed 6 years · 97223Verify license
Suncatcher Windows LLCWindow and glass contractor · licensed 6 years · 97214Verify license
Sash & Cord Window Restoration LLCWindow and glass contractor · licensed 4 years · 97218Verify license

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