A Tacoma waterfront property with years of undetected moisture intrusion. By the time the owner called, dry rot had consumed the south-facing mudsill, 28 linear feet of rim joist, and compromised subfloor framing in two rooms. This is what a complete dry rot repair in Tacoma looks like — from forensic diagnostic to permanent structural rebuild.
The owner had noticed soft flooring near the south wall of the living room and a persistent musty smell in the crawl space. A home inspector flagged "possible wood damage at foundation" but could not quantify scope. The owner's concern: a deal was pending and the buyer's agent was asking for a contractor letter within five days.
Waterfront properties in Tacoma face an accelerated dry rot exposure pattern. Grade-level splash-back from hard surfaces, combined with the narrow drying window the PNW winter provides, keeps mudsill and rim joist moisture content elevated for months at a time. On this property, failed kick-out flashing at a roofline above the south wall had been directing roof runoff directly onto the foundation siding for several seasons. The moisture source was not visible from grade — it required a crawl space entry and moisture meter survey to locate.
Full crawl space access with moisture meter readings at 6-inch intervals along all foundation walls. South wall readings came in at 28–34% MC — well above the 19% threshold where fungal activity sustains. North and east walls were dry. This told us immediately: one concentrated moisture source, not a systemic drainage problem.
Exterior inspection from a ladder confirmed the source. A kick-out flashing at the south roofline junction had separated from the wall, allowing roof runoff to track behind the siding and pool at the mudsill for an estimated 3–5 seasons. Rot was not random — it mapped exactly to the moisture delivery zone.
Full excision mapping completed in the crawl space: 28 linear feet of rim joist with active decay, the full south-wall mudsill run (22 LF), and two floor joist bays where subfloor sheathing had delaminated. Written findings delivered to the owner and their agent within 24 hours of the diagnostic visit.
Dry rot repair in Tacoma is not patch work. Fungi travel through wood fiber well beyond the visibly discolored zone. Our standard is to excise to clean wood confirmed by probe and moisture meter, treat all adjacent framing with a borate-based fungicide, and rebuild with pressure-treated lumber where ongoing moisture exposure is possible.
Repair completed in 7 working days from diagnostic. Contractor letter delivered to the listing agent on day 2 after scope confirmation — the buyer's lender required it and the deal stayed on track. Post-repair moisture readings on the south wall came in at 11–13% MC — well within safe range.
The owner received a 5-year written structural guarantee covering all replaced framing. The moisture source — the kick-out flashing failure — was corrected as part of the repair scope. The rot cannot return unless a new moisture source develops, and the owner now knows what to watch for.
Total project value: $11,400 lump sum, all-in. The $350 diagnostic fee was credited in full toward the repair.
Every wet season it advances further into your framing. A $350 diagnostic tells you exactly what you have, exactly what it costs to fix, and whether it's urgent. No free estimates. No guessing.
253-891-9622