Building Information and Resources

COVID-19 Update

Columbia County is currently operating in Phase 3 of Safe Start Washington. All construction, including those activities for which social distancing may not be maintained and the start of new construction projects, is authorized to resume. ALL construction must adhere to Phase 2 Construction COVID-19 Job Site Requirements (PDF) issued May 12 and updated July 2, 2020.

The Home Builders Association of the Tri-Cities website has additional information as well as templates for the required job site postings, including a safety plan, visitors log and a toolbox training and sign-in sheet.

Please contact us directly at:
Clint - (509) 382-3941/Email Clint Atteberry
Dena - (509) 382-3938/Email Dena Martin


Pay for your permit online with a debit or credit card via our Permit Payment page.

*Minimum $2 or 2.5% convenience fee applies.

We can also accept checks made out to Columbia County Treasurer or exact cash mailed or delivered to our office located at:
Columbia County Planning and Building
114 S 2nd Street
Dayton, WA 99328



Please call (509) 382-3941 or email Clint Atteberry to request a building, mechanical or plumbing inspection. Please allow 24-hour notice.

Required inspections* include, but are not limited to:

  • footings
  • foundation walls
  • underground plumbing installation and pressure test
  • gas piping installation and pressure test
  • rough plumbing installation and water line pressure test
  • rough-in mechanical installation
  • weatherproofing and framing
  • insulation
  • drywall attachment
  • final

*Not all inspections are required for all permit types. Issued permits will list the required inspections.

Electrical inspections are performed by the Washington State Department of Labor and Industries and may be requested by visiting the Department of Labor and Industries website.

For water/septic inspections contact Andrew Maycumber by email or by calling (509) 524-2669.

Residential Design Requirements

Snow Load: 30 pounds per square foot below 2,500 feet above mean sea level; call (509) 382-4676 for requirements greater than 2,500 feet above mean sea level as determined by Snow Load Analysis for Washington.

Wind speed: 110 miles per hour

Seismic Category: C

Weathering Probability for Concrete: Severe

Frost Line Depth: 18 inches

Termite Potential: slight to moderate

Winter Design Temperature: 6 degrees

Ice Barrier: Not required, but recommended

Flood Hazard: FIRM, adopted 1988

Air Freezing Index: 800

Climate Zone: 5b

Insulation: Ceiling - R49; Wood Frame Wall - R 21 or R13 + R10; Floor R30; Basement Wall and Crawl Space - R15/19

Adopted Building Codes

International Building Code, Standards and amendments 2018 - WAC 51-50
International Residential Code, Standards and amendments 2018 - WAC 51-51
International Mechanical Code, Standards and amendments 2018 - WAC 51-52
International Fire Code, Standards and amendments 2018 - WAC 51-54A
Uniform Plumbing Code, Standards and amendments 2018 - WAC 51-56