Dry Rot Repair Cost in Portland and Vancouver WA: 2026 Pricing Guide
Real 2026 dry rot repair cost ranges for siding, decks, windows, and structural framing in Portland and Vancouver WA.
In the Pacific Northwest, dry rot is less an occasional repair and more a fact of life. The combination of long wet winters, mild summers, and homes built largely with western softwoods creates ideal conditions for the fungi that cause it. By the time you spot dry rot, it has usually been working on the wood for a year or longer.
This is a 2026 pricing guide for the Portland and Vancouver WA markets. It walks through what drives the cost of dry rot repair, real ranges by area of the home, how a proper repair is actually done (and where cheap fixes go wrong), and how to know when to stop researching and call a pro.
If you want a free dry rot inspection in the Portland or Vancouver WA metro, NW Reliable Home Services can be reached at (360) 713-8022.
What Drives Dry Rot Repair Cost
Cost is set by four things: how far the rot has spread, where it is (cosmetic trim vs structural framing), how hard it is to access, and whether the moisture source needs to be addressed as part of the repair.
Extent of damage
A two foot section of rotted fascia is a one day repair. A full siding wall with rot that has reached the sheathing and studs is a multi week project. The single biggest variable is what is hidden behind the visible damage.
Location
Trim, fascia, and exterior molding are the cheapest to repair. Window frames, door jambs, and decking are mid range. Roof rafters, structural beams, and ledger boards are the most expensive because of access and load.
Accessibility
Second story siding, hard to reach window sills, and rot under decking that requires lifting boards all add labor. A one story rambler is cheaper to repair than a three story Hawthorne foursquare.
Moisture source
A real repair includes fixing the source. That can be as simple as recaulking a window or as involved as new flashing, gutter repair, or grading. Skipping this step is the most common reason repairs come back.
Average Dry Rot Repair Cost by Area (2026)
These are typical 2026 Portland and Vancouver WA ranges. Each one assumes the moisture source is addressed and the surrounding wood is treated to prevent recurrence.
| Area of the home | Typical cost range |
|---|---|
| Small trim or fascia section | $300 to $1,200 |
| Window frame or sill | $400 to $1,500 |
| Exterior door jamb | $400 to $1,000 |
| Siding (single area, including replacement) | $1,000 to $5,000 |
| Deck framing repair or post replacement | $1,500 to $8,000 |
| Deck ledger board replacement | $2,500 to $6,500 |
| Roof rafter or sheathing repair | $1,500 to $10,000 |
| Major structural rot project | $8,000 to $25,000 plus |
Insurance does not usually cover dry rot because it is classified as a maintenance issue. The exception is when dry rot was caused by a sudden covered event such as a burst pipe.
How Dry Rot Repair Actually Works (And Where Cheap Fixes Fail)
1. Probe the full extent of damage
We use an awl or screwdriver to probe past the obviously rotted wood until we hit sound, dense wood. The damage is almost always larger than the visible area. Rule of thumb: extend the cut at least 18 inches past the last point of probe penetration.
2. Cut back to sound wood
We remove all soft, fibrous, and discolored wood. Half measures here are the number one reason dry rot returns. If a board has been carrying a fungal colony, leaving even a section behind reseeds the same area.
3. Treat surrounding wood with a borate fungicide
Borate based wood preservatives penetrate and remain active for decades. We treat the cut edges and any sound but adjacent wood. This step is invisible after paint goes on, which is part of why cheap repairs skip it.
4. Replace with the right material
Structural framing is replaced with kiln dried pressure treated lumber. Trim and siding is replaced with the same material to match (cedar, fiber cement, LP, T1-11), primed on all six sides before install.
5. Address the moisture source
Almost every dry rot repair we do includes some moisture remediation: new flashing, fresh caulk, gutter repair, drainage correction, or in some cases improved ventilation. Without this, the repair has a one to three year shelf life.
6. Prime and finish
New wood gets sealed on all sides before install, primed after install with an exterior bonding primer, and finished with a quality acrylic exterior paint. PNW UV and rain are merciless on raw or single coat finishes.
Cheap Patch vs. Permanent Repair: Why the Difference Matters
There is a category of repair that uses epoxy filler troweled over rotted wood and sanded smooth. It looks great for six months. It fails by the second wet season because the underlying fungus is still active and the moisture source has not been addressed. The cheap repair almost always costs more than the right one within three years.
How to Compare Dry Rot Repair Quotes Fairly
When you collect two or three estimates for the same job, the prices often vary by 30 to 60 percent. That is not because contractors are pricing arbitrarily. It is because they are quoting different scopes. Make sure each estimate answers the same questions before you compare line totals.
- How far past the visible damage does the contractor plan to cut back? The right answer is at least 18 inches past the last point of probe penetration.
- Will the surrounding wood be treated with a borate fungicide? Cheap quotes often skip this.
- What material will be used for replacement, and how will it be primed? Pressure treated lumber for framing; primed on all six sides before install for trim and siding.
- How will the moisture source be addressed? A real scope names the specific moisture issue (flashing, caulk, gutters, ventilation) and includes a fix.
- What is the warranty on the repair? Reputable contractors warranty their work for at least one year, and often longer when the moisture source is also corrected.
Real World Cost Examples From Portland and Vancouver Homes
These are anonymized examples of real PNW dry rot projects. They are useful as a sanity check when you are comparing your estimate to industry averages.
Example 1: 1962 Vancouver ranch, two window sills and adjacent siding
Single elevation, both bedroom windows on the north wall showed soft sills and bubbling paint at the bottom corners. The damage had reached the bottom of the siding course below each window. Total scope included sill replacement, siding section replacement, sheathing repair on one window, borate treatment, new flashing, paint match. Total cost was $3,250.
Example 2: 1996 Beaverton two story, deck framing
A 12 by 14 elevated deck with rotted ledger, two failed posts at ground level, and three soft joists at the house side. Scope included full deck removal, ledger replacement with through bolts and Z flashing, two new posts with new concrete piers, sister and replace joists, reinstall composite decking. Total cost was $9,800.
Example 3: 1925 Northeast Portland bungalow, exterior trim and porch posts
Front porch with rotted base on three columns and rotted trim around the porch roof beam. Scope included support and remove columns, cast new concrete bases, install new pressure treated columns wrapped in primed cedar to match, replace rotted trim, prime and paint. Total cost was $6,400.
How NW Reliable Home Services Approaches Dry Rot in PNW Homes
We start with a free inspection. We probe, photograph, and write a clear scope that explains exactly what we found and how we will fix it, including the moisture source. We use borate treatment on adjacent wood, replace with the right materials, and finish so the repair blends. We are licensed in both states (OR CCB# 255838 and WA NWRELRH777) and serve Portland, Beaverton, Hillsboro, Gresham, Tigard, Lake Oswego, West Linn, Oregon City, Milwaukie, and Tualatin, and Vancouver, Camas, Washougal, Battle Ground, Ridgefield, La Center, Brush Prairie, and Hazel Dell.
To schedule a free dry rot inspection, call (360) 713-8022 or visit nwreliablehomeservices.com.
Frequently Asked Questions
How much does dry rot repair cost?
Small repairs (trim, fascia, single window sill) run $300 to $1,500. Mid sized repairs (siding sections, deck framing, multiple window frames) run $1,500 to $8,000. Large structural projects can run $10,000 to $25,000 or more.
Is dry rot covered by homeowners insurance?
Almost never. Insurance treats dry rot as the result of long term moisture exposure and excludes it as a maintenance issue. The exception is when the rot was caused by a sudden covered event such as a burst pipe, and you reported it promptly.
Can dry rot be treated without replacing the wood?
Only in the earliest stages, where the wood is still structurally sound. Once wood has lost density and fibrous structure, it has lost its strength and needs to be replaced. Borate treatment alone does not restore lost wood.
How long does dry rot repair take?
Small repairs are a one to two day job. Mid sized siding or deck work runs three to seven days. Large structural projects run two to four weeks plus permitting time.
How do I prevent dry rot from coming back?
Address the moisture source, keep paint and caulk in good condition, clear gutters and downspouts, ensure good attic and crawlspace ventilation, and keep landscaping plants and irrigation away from siding and trim.
If you have soft wood you can poke a screwdriver into, call NW Reliable Home Services at (360) 713-8022 for a free inspection in the Portland or Vancouver WA metro.
