In short: Washington sellers of most homes must give buyers the Form 17 seller disclosure statement under RCW 64.06, and known mold or past mold remediation belongs on it. Fixing the problem properly before listing, with photos, moisture readings and an independent clearance report, usually costs less than the credit a buyer will ask for once an inspector finds it.
This page is general information for Washington homeowners, not legal advice. Talk to your real estate broker or attorney about your specific sale.
What Form 17 means for mold
- Most residential sellers must complete it. RCW 64.06 requires sellers of most one-to-four-unit residential property to deliver the Seller Disclosure Statement, usually Form 17.
- It's due within 5 business days of mutual acceptance unless the buyer waives it in writing.
- It's based on what you actually know. You're not required to inspect, but you must disclose known problems.
- Buyers can rescind. After receiving the disclosure, buyers have a short window, three business days under the statute, to back out.
- Mold fits several questions on the form: past leaks, water intrusion, and environmental conditions. Known mold and past mold remediation should be disclosed.
Selling "as-is" doesn't remove the duty to disclose what you know.
Fix it first, or disclose and negotiate?
Fixing before you list
- You control the scope, the contractor and the price
- You hand buyers a clearance report instead of a question mark
- The home inspection has less to find
- Usually best for crawl space, attic and bathroom mold with a clear cause
Disclosing and negotiating
- Faster to market if time is tight
- Buyers price in worst-case numbers and a margin for the hassle
- Risk of a renegotiation or a cancelled deal at inspection
- Makes sense when the work is large and a buyer may want to choose their own contractor
What buyers and their inspectors look for
In Bothell, the usual findings are stained attic sheathing (often from bath fans venting into the attic), growth on crawl space joists with a torn vapor barrier, and old leak stains under bathrooms and around windows. A buyer's inspector will often write "microbial growth" and recommend further evaluation, which can stall a deal.
What settles a buyer's nerves:
- The written scope: the cause, the areas and what was done
- Before-and-after photos
- Moisture readings showing materials are dry
- An independent clearance report
- Proof the moisture source was fixed (fan ducting, new vapor barrier, plumbing invoice)
Timeline: fitting mold work into a sale
Pre-listing inspection
Ideally 3–6 weeks before you list, so there's time to fix things. Book an inspection.
Remediation
Most crawl space, attic and bathroom jobs take 1 to 5 days on site.
Clearance testing
Independent post-remediation verification, with results commonly in a few business days. How it works.
Disclosure packet
Disclose on Form 17, and attach or reference the scope, photos and clearance report.
Already under contract and the buyer's inspector found it? Call right away with your inspection-response deadline. A written scope and range can turn an open-ended credit request into a specific number.
Common Bothell scenarios
Stained attic sheathing
Usually condensation from bath fans or poor ventilation. Clean the sheathing, duct the fans outside, and clear the eave vents. Attic mold remediation.
Crawl space growth
Common under 1970s–90s homes. Clean the framing, remove wet insulation, and install a proper vapor barrier. Crawl space remediation.
Sources
- RCW 64.06 – Real property transfer disclosures (Washington State Legislature)
- Washington seller disclosure requirements – study guide
- Washington seller disclosure requirements – AskDoss