Mold Inspection & Remediation in Washington

No state mold license. Washington does not license or certify mold inspectors, assessors, or remediators, and no state agency sets standards for how residential mold cleanup must be done. The checking falls to you.

Contractor registration. Contractors in Washington must register with the Department of Labor & Industries under chapter 18.27 RCW. Use L&I's "Verify a contractor" lookup to confirm that the company is registered, bonded, and insured before it starts work, especially if the job includes rebuilding drywall, flooring, or framing.

What to ask for. Ask for the crew's training or industry certifications, a certificate of general liability insurance, and a written scope listing rooms, materials, and how the result will be checked. Many companies follow the ANSI/IICRC S520 standard. Washington does not stop one company from both testing and remediating; an independent inspection before work and a separate final check give you a second opinion.

Western Washington's rain comes slowly and for a long time. NOAA's 1991–2020 normals put Seattle's Sand Point station at about 38 inches of precipitation a year, and roughly 70% of it falls from October through March, with July close to dry. The wet months are also cool and cloudy, so materials that get damp dry slowly, and warm, moist indoor air condenses on cold windows, exterior walls, and the underside of roofs. Eastern Washington is far drier, and mold there usually points to a specific leak.

The EPA recommends drying wet materials within 24 to 48 hours and keeping indoor humidity below 60%, ideally 30% to 50%. Bathroom and kitchen fans, and a dehumidifier in basements and crawl spaces during the wet season, do a lot of the work in a Puget Sound house.

Washington homeowners policies usually separate sudden water from slow moisture. A burst pipe, a failed water heater, or a supply line that splits is the case a homeowners policy is most likely to cover, often with a separate limit for mold. Mold from condensation, a damp crawl space, or a slow roof leak through a long wet season is commonly treated as gradual or maintenance and excluded.

Water that backs up through a drain needs a backup endorsement, and flood water, including river flooding, needs a flood policy. Photograph damage before cleanup and report promptly. The Washington Office of the Insurance Commissioner helps consumers with claim questions and complaints. See does insurance cover mold.

Our phone line is for homeowners. If you rent in Washington, the Residential Landlord-Tenant Act gives you some protection. Under RCW 59.18.060, landlords must keep the unit reasonably weathertight and must give tenants information from the Department of Health about mold and how to limit it.

Give your landlord written notice of the leak or moisture problem and keep a copy, along with dated photos. RCW 59.18.070 sets time limits for the landlord to start repairs after written notice, and the remedies that follow are specific, so read them or talk to a tenant organization or legal aid office before withholding rent or making repairs yourself. For your belongings, see renters insurance and mold.