Columbia County Washington Energy Code Compliance
WSEC-R 2021 compliance information for builders and contractors in Columbia County.
Code environment
Climate Zone
CZ5
Eastern Washington — stricter insulation and air-sealing minimums apply.
Wall min R-20 or R-13+5ci · Ceiling min R-49 · Window max U-0.28 (WAC 51-11R-40202)
Radon Zone
Zone 2
Moderate radon potential — radon-resistant construction recommended but not mandated by state code.
Learn more →County building department
The county building department handles permits for unincorporated areas. Cities within the county may have their own permit offices — see below.
Authority Having Jurisdiction (AHJ)
Columbia County Planning & Building
- Phone
- (509) 382-4676
- Address
- 114 S 2nd St, Dayton, WA 99328
- Hours
- M-F 8:30am-4:30pm
- Notes
- Dayton and Starbuck defer to county
Last verified: 2026-04-19
Ready to check your compliance?
Answer a few questions about your project and get a complete R406 credit summary you can submit with your permit application.
Start your WSEC compliance check →Typical project costs in Columbia County
Coming soon as we gather receipt data from local contractors.
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