What causes dry rot in Tacoma homes?

Dry rot in Tacoma homes is caused by a wood-decaying fungus (Serpula lacrymans and related species) that activates in wood with moisture content above 20%. Despite the name, dry rot requires moisture to start — it just continues spreading into drier wood once established. Tacoma's wet climate, aging housing stock, and older drainage and flashing details make conditions ideal for dry rot in crawl spaces, sill plates, exterior siding, porch framing, and window and door surrounds.

How do I know if I have dry rot vs regular wood damage?

Dry rot has specific visual indicators: the wood appears darkened, cracked in a cube-like pattern, and crumbles or falls apart easily when probed rather than splintering. It often has a musty, fungal smell. Surface paint may bubble or peel above affected areas. A screwdriver or awl pushed into suspect wood will penetrate easily if rot is present — structurally sound wood resists the probe. A forensic diagnostic is the only reliable way to map the full extent of infection.

Can you just paint over dry rot or treat it with a hardener?

No. Epoxy fillers and wood hardeners are cosmetic solutions that do not eliminate the fungal organism or the moisture condition that caused it. The rot continues spreading behind and beneath the repair. For any structural member — joist, sill plate, rim joist, post, beam — full physical excision of all infected material is required. For non-structural trim and fascia, epoxy consolidants are occasionally appropriate, but only after the moisture source is corrected and the affected area is fully dried.

Does dry rot spread to adjacent wood if not treated?

Yes. Dry rot fungus produces mycelium strands that actively conduct moisture from wet areas to dry ones, enabling spread into wood that would otherwise be too dry to support decay. This is what makes dry rot more aggressive than wet rot. An active dry rot colony in a sill plate will spread into rim joists, subfloor, and floor joists if the moisture source is not corrected and the infection is not fully excised. Early intervention is always the smaller and cheaper repair.

What do dry rot treatment companies actually do and what should I look for?

Dry rot treatment has two required components: physical removal of all infected wood fiber and fungicide treatment of the remaining substrate. Any contractor who applies a surface treatment without first excising the infected wood is concealing the problem, not fixing it. The fungal organism lives inside the wood fiber — surface treatments cannot reach it. A legitimate dry rot repair contractor will excise all infected material to clean, sound wood; apply borate or appropriate fungicide to adjacent surfaces; identify and correct the moisture source; and replace with appropriately specified structural material. That is the only treatment sequence that prevents recurrence.

Tacoma · Pierce County · Gig Harbor · Direct GC Work — #APCONL*825QO

Dry Rot Repair
Tacoma WA

Dry rot is a living organism. Painting over it, filling it with epoxy, or ignoring it does not stop it — it feeds it. As Tacoma's dry rot contractors, we excise all infected material, treat the substrate, rebuild structurally, and correct the moisture condition that caused the rot to start. That is the only repair that holds — and the reason homeowners searching for dry rot contractors Tacoma trust licensed general contractors over painters or cover-up patchwork.

Full rot excision — no partial cuts, no filler patches on structural members
Structural framing: sill plates, rim joists, floor joists, posts, beams
Exterior envelope: siding, trim, fascia, soffit, porch framing
Window & door surrounds — rot mapping before scope
Fungicide treatment of adjacent substrate after excision
Moisture source correction concurrent with every repair

Book a $350 Rot Diagnostic 📞 253-891-9622

Start Here

^$350

Forensic Rot Diagnostic

Full infection mapping — probe & assess
Moisture source identification
Written findings with photos
Fixed lump-sum repair proposal
Structural vs. cosmetic scope delineated

Book a $350 Diagnostic

$350 credited in full toward your repair when you move forward.

Direct Answer

Dry Rot Repair in Tacoma, WA — Direct Answer

Dry rot repair means cutting out wood-decay fungus damage back to sound material, replacing the structural members that were lost, and eliminating the moisture path that fed the decay. Coating or filling decayed wood is not a repair. Realty Repair Co. (APCON LLC, Washington General Contractor #APCONL*825QO) performs this work directly as the general contractor in Tacoma, Washington. Scope is confirmed on site with moisture meters and physical probing before any price is issued; the resulting repair contract is lump-sum fixed price, not hourly, and structural repairs carry a five-year written guarantee.

Work performed: full rot excision to sound wood, structural member replacement, moisture source correction, exterior and crawl space framing rebuild
How it starts: $350 forensic structural report — on-site, written, photographed. Credited 100% against the repair contract if you proceed.
Pricing method: Lump-sum fixed price issued after the failure boundary is confirmed. No hourly billing. No open-ended scope.
Guarantee: Five-year written guarantee on structural repairs.
Licensing: WA General Contractor #APCONL*825QO, bonded and insured. Work performed under the 2021 Washington State Residential Code (WAC 51-51, effective March 15, 2024).
Not offered: Crawl space encapsulation, waterproofing, basement finishing, painting, pressure washing, landscaping. Plumbing, electrical and mechanical are coordinated through separately licensed contractors per RCW 18.27.
Contact: 253-891-9622 · dispatch@realtyrepairco.com · 711 115th St S, Tacoma, WA 98444

Reviewed by Dindar Nasim, owner and Washington licensed general contractor (#APCONL*825QO) · Updated October 13, 2026

Understanding Dry Rot

Why Tacoma Homes
Are High Risk

The Pacific Northwest's wet climate, combined with Tacoma's aging housing stock and frequent deferred maintenance on flashing and drainage, creates near-ideal conditions for fungal decay. Understanding how rot works is why our repairs hold and patch jobs don't. As experienced dry rot contractors serving Pierce County, we've seen every failure pattern Tacoma's housing stock produces — and we know exactly how to stop it.

The Biology

Dry Rot Is a Living Fungus

Dry rot (primarily Serpula lacrymans and related species) is a wood-decaying fungus, not simple moisture damage. It produces mycelium strands that actively transport moisture from wet areas to dry ones — which is why it can spread into wood that appears dry. Killing the fungus requires physical removal of infected material and substrate treatment. You cannot paint or seal over an active colony.

The Trigger

Moisture Content Above 20%

Wood with moisture content below 20% will not sustain fungal decay. In Tacoma, moisture intrusion sources include failed flashing, clogged gutters, grade slope toward the foundation, crawl space condensation, and failed window or door caulking. Correcting the source is not optional — a repair without moisture correction is a temporary repair, regardless of how well the carpentry is executed.

The Risk

Rot Spreads Aggressively

A dry rot colony discovered in exterior siding is often already present in the sheathing beneath it. A colony in a rim joist is often tracking into the sill plate and adjacent floor joists. Surface-visible rot represents the minimum scope — actual infection extent is always determined by probe and is frequently larger than what's visible. This is why we map infection before we quote. Homeowners searching for dry rot treatment companies near me or dry rot remediation services in Tacoma will find we are the only licensed GC in this market who maps the full infection boundary before issuing a price — rather than discovering additional scope after work begins.

The Fix

Full Excision — No Exceptions

For any structural member, the only permanent repair is complete physical removal of all infected material — cutting past visibly affected wood until clean, sound fiber is reached — followed by fungicide application to the remaining substrate and rebuild with appropriate species and treatment level. We do not use epoxy consolidants on load-bearing members. Cosmetic applications are appropriate only for non-structural trim.

Warning Signs

How to Identify
Dry Rot

🠯

Cuboidal Cracking

Wood cracked in a distinctive cube-like or checkerboard pattern — different from splitting grain — is a signature of advanced dry rot fungal activity.

🎨

Paint Bubbling or Peeling

Paint lifting or bubbling on exterior siding, trim, or window surrounds — particularly on north-facing or shaded elevations — often indicates rot in the substrate beneath.

👃

Musty Fungal Odor

A persistent musty smell in the crawl space, near exterior walls, or around windows and doors is often active fungal decay, not just moisture. Source must be identified and stopped.

🏚

Soft Spots in Siding or Trim

Exterior wood that feels soft, spongy, or hollow when pressed — especially at the bottom of siding boards, fascia ends, or window sill nosings — is actively decayed.

🕳

Visible Discoloration in Crawl Space

Dark brown or black discoloration on floor joists, sill plates, or rim joists — especially near exterior walls and low-bearing points — indicates active or historical fungal decay.

🚶

Soft or Spongy Floor Areas

Floor soft spots near exterior walls — particularly in bathrooms, kitchens, and entry areas — often indicate rot in the subfloor or underlying floor joists from chronic moisture intrusion.

🌫️

White or Gray Fungal Growth

Visible white, gray, or silky fungal strands (mycelium) on wood surfaces in the crawl space or on structural framing. Active colony — requires immediate assessment.

🏠

Porch Post or Deck Post Failure

Porch posts that rock, lean, or feel soft at the base have almost certainly experienced post base or sill rot. The post is cosmetically intact but structurally failed.

Scope of Services

What We Repair —
Every Rot Location

Dry rot reaches every part of a wood-framed exterior. We repair all of it — from structural framing in the crawl space to trim details at the roofline. Our dry rot experts assess the full infection boundary before scoping any repair. Whether you need a dry rot specialist for a single window surround or a comprehensive structural rot rebuild, the entry point is the same $350 diagnostic.

🛡️

License Note: All carpentry, framing, and rot repair work is performed directly by APCON LLC under GC License #APCONL*825QO. If rot remediation exposes plumbing or electrical systems requiring licensed trade work, those scopes are GC-coordinated under RCW 18.106 and RCW 19.28 respectively.

Sill Plate & Rim Joist Rot

The most common structural rot location in Tacoma's housing stock. Where framing meets foundation — perpetually exposed to ground moisture and splash-back. Full excision required; no partial repairs on bearing members.

Full rot excision to clean, sound fiber
Fungicide treatment of foundation sill surface
Pressure-treated replacement sill installation
Rim/band joist replacement concurrent
Sill seal and moisture barrier restoration
Drainage correction recommendation

Floor Joist & Subfloor Rot

Crawl space moisture, failed vapor barriers, and standing water create conditions for joist rot. We map the full infection extent — which always exceeds what's visible from below — before scoping repair.

Full infection mapping via probe before scope
Rot excision and treated lumber installation
Joist sistering where infection is limited
Full replacement where depth exceeds 50%
Subfloor replacement concurrent as required
Vapor barrier repair or full replacement

Exterior Siding & Sheathing Rot

Failed caulking, inadequate flashing, and grade issues allow moisture behind siding. Sheathing rot frequently exists behind intact-looking surface material. We expose, map, and rebuild correctly.

Siding removal to expose sheathing
Full sheathing infection mapping
Sheathing replacement as required
Moisture barrier and flashing correction
New siding installation — species and treatment matched
Caulking and paint-ready finish

Porch & Deck Structural Rot

Post bases, beam ends, ledger connections, and decking are all high-risk rot locations. We assess the full structural condition before any cosmetic repair — a rotten post base under an intact-looking column is a safety issue, not an aesthetic one.

Post base assessment and full replacement
Beam end rot excision and sister or replace
Ledger board rot — full removal, new flashing, reinstall
Decking rot replacement with treated lumber
Post cap hardware — corrosion-resistant spec
Drainage slope correction

Fascia, Soffit & Trim Rot

Fascia and soffit rot is often the first visible indicator of a moisture problem that has already reached the framing behind it. We assess depth of infection before treating as cosmetic scope.

Rot depth assessment — cosmetic vs. structural
Full replacement for structural involvement
Epoxy consolidant for non-structural trim only
Gutter and downspout alignment correction
Paint-ready primed finish
Adjacent framing inspection concurrent

Window & Door Surround Rot

Failed window caulking and improper flashing allow water to track into the rough opening framing — invisible from outside until the rot is advanced. We assess headers, sill horns, and jack studs before scoping.

Surround removal and rough opening inspection
Header, jack stud, and sill horn assessment
Structural framing replacement if infected
Pan flashing installation at reinstall
New surround installation with proper caulk detail
Paint-ready finish throughout

Our Method

Map the Infection.
Cut It Out. Close It Right.

The most common dry rot repair failure is underscoped excision — cutting to the edge of visible rot rather than probing to find where the infection actually ends. We map first, every time.

Book a $350 Rot Diagnostic

Schedule online or call. We arrive with probes, moisture meters, and full crawl space access capability. The $350 diagnostic fee credits 100% toward your repair. Why we charge for diagnostics →

Full Infection Mapping

We probe systematically beyond the visible damage boundary to find where sound wood actually starts. Moisture readings taken at all suspect locations. We do not scope from a visual walkthrough.

Moisture Source Identified

We trace the moisture path that produced the rot condition — failed flashing, drainage grade, crawl space condensation, clogged gutters. The source is documented in your written report.

Written Findings + Fixed Lump-Sum

You receive a documented report with infection extent, moisture source, and a fixed lump-sum repair price. Structural vs. cosmetic scope is clearly delineated. One price — no surprises after the wall opens.

Full Excision + Moisture Correction

Infected material is physically removed to clean fiber. Substrate receives fungicide treatment. Moisture source correction is executed concurrent with structural rebuild — not deferred to a second visit.

5-Year Guarantee Issued

Because we correct the moisture source, the rot does not come back from that source. We back that with a written 5-year guarantee. Same rot location fails from our repair — we return, no charge, no paperwork.

Book Your Rot Diagnostic

^$350

Forensic Rot Diagnostic · Credited Toward Repair

Probe-based infection mapping
Moisture source identification
Written findings + photo documentation
Structural vs. cosmetic scope delineated
Fixed lump-sum repair proposal
$350 credited 100% toward repair

Book a $350 Diagnostic 📞 253-891-9622

✓ 5-Year Written Guarantee on All Rot Repairs

Fixed Once.
Fixed Right.
Fixed for Good.

Dry rot returns when moisture returns. A perfectly executed rot repair that leaves the moisture source unaddressed will fail again — typically within two to four wet seasons. This is the exact failure mode behind every "the contractor already fixed this" conversation we have with new clients.

Our process requires identifying and correcting the moisture source concurrent with the structural repair. We do not schedule the drainage correction for a future visit. We do not leave the moisture condition in place and rebuild over it. Both problems are solved in one scope.

When the moisture source is corrected and all infected material is fully excised, the fungal colony has no path to re-establish. We back that with a written guarantee: same rot location fails from our repair within five years, we come back at no charge. No paperwork. No runaround. One call.

5-Year Written Guarantee — All Dry Rot Repairs

Common Questions

Dry Rot Repair
FAQ

Dry rot is caused by wood-decaying fungi — primarily Serpula lacrymans — that activate when wood moisture content exceeds 20%. Tacoma's wet climate creates ideal conditions, but the specific triggers in local homes are usually failed flashing details, clogged or undersized gutters, negative grade sloping toward the foundation, inadequate crawl space ventilation or vapor barriers, and failed window and door caulking. Tacoma's aging housing stock — built before modern moisture management practices — makes these failures common and frequently compounding.

No — not on structural members. Epoxy hardeners and fillers are cosmetic solutions that do not kill the fungal organism or stop it from spreading. The colony continues beneath the surface repair. For load-bearing members — joists, sill plates, posts, beams — full physical excision is required. Epoxy consolidants are only appropriate on non-structural trim where the infection is confirmed to be surface-only, the moisture source has been corrected, and the wood has fully dried. We will tell you which category your situation falls into during the diagnostic.

Cost is entirely dependent on infection extent, location, and whether the affected members are structural or cosmetic. Trim and fascia items are bundled into the $4,000 minimum project. Structural dry rot — sill plates, rim joists, floor joists — typically runs $4,000–$12,000 depending on linear footage and concurrent moisture correction scope. Porch structural rot typically runs $4,000–$6,500 depending on post, beam, and ledger condition. Our $350 diagnostic maps the full infection and delivers a fixed lump-sum price — not a range that grows once we open the wall.

Yes — aggressively. Dry rot fungus produces mycelium strands that actively transport moisture from wet areas to dry ones, enabling spread into wood that would otherwise be too dry to decay. An active colony in an exterior sill plate will track into the rim joist and floor joists. A colony behind failing siding will spread into sheathing and framing. Early diagnosis is always the smaller and cheaper repair. The longer rot sits, the larger the structural scope becomes.

Book the $350 diagnostic immediately. We assess the flagged conditions, map the full infection extent (inspector reports routinely underestimate actual scope because inspectors do not probe), and deliver a written contractor document and fixed lump-sum repair price suitable for your agent and the transaction. For pre-listing and inspection findings, we typically turn written diagnostics around in about three days. Your closing timeline is manageable if you move quickly — it stops being manageable if you wait.

Standard homeowners insurance policies in Washington State generally exclude dry rot as a maintenance issue rather than a sudden-event loss. However, if the rot was caused by or concurrent with a covered water event — a pipe burst, storm damage — a portion of the structural repair scope may be claimable. We provide photo-documented repair reports that clearly identify causation — which is useful when presenting a mixed claim to your insurer. We are not a public adjuster and cannot advocate your claim, but our documentation gives you the strongest possible factual record.

Dry rot treatment has two components: physical removal of all infected material and fungicide treatment of the substrate that remains. Any company that applies a surface treatment without first excising the infected wood is not treating dry rot — they are concealing it. The fungal organism lives in the wood fiber. Surface treatments cannot reach it. What you should look for in a dry rot repair contractor: full physical excision to clean, sound wood fiber; borate or appropriate fungicide applied to all adjacent wood surfaces after excision; moisture source identified and corrected; and structural replacement with appropriately specified material. That is what we do on every dry rot repair — it is the only treatment that prevents recurrence.

Often Combined With

Related Services

Dry rot is rarely an isolated finding. These services are frequently scoped and executed concurrently.

Recognizing the Signs

Noticing Something Wrong
With Your Floors?

Dry rot in the crawl space and floor framing produces specific surface symptoms before most homeowners know there is a structural problem. These symptom guides explain what you are experiencing and why it traces back to this service.

Dry Rot Doesn't
Stop On Its Own.

Every wet season an untreated rot colony is active, it expands its footprint. The repair you defer today is a larger repair next year. If you're searching for a dry rot specialist near me, dry rot contractors near me, dry rot repair contractors near me, or wood rot repair near me in Tacoma or Pierce County, book a $350 diagnostic — our dry rot experts map the infection, find the moisture source, and give you a fixed price to solve it permanently.

253-891-9622

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