Spokane County Washington Energy Code Compliance
WSEC-R 2021 compliance information for builders and contractors in Spokane 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 1
High radon potential — passive sub-slab depressurization system required under WAC 51-51-60101 (Appendix AF).
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)
Spokane County Building & Planning Department
- Phone
- (509) 477-3675
- Address
- 1026 W Broadway Avenue, 1st Floor, Spokane, WA 99260
- Hours
- M-Th 7:30am-4pm F 7:30am-noon
Last verified: 2026-04-19
Submittal notes
- Spokane City + Spokane County: Spokane City and Spokane County both require 2021 Duct Leakage Affidavits for new construction AND existing-home remodels before final occupancy — note in the submittal package that the affidavit will be provided at final.
Cities with their own building department
These cities have an independent permit office. If your project is inside city limits, contact the city — not the county — for permits.
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 Spokane County
Coming soon as we gather receipt data from local contractors.
Information on this page may be out of date. Report outdated info →