Most Portland-area dry rot repairs on trim, sills and fascia land between $500 and $4,000, materials included, and $1,500 is the typical bill (local market figures, November 2026). A rotted window sill by itself is typically about $600 and a door frame about $800, both labour only . How deep the rot goes, what's soft behind it and the leak that caused it decide the rest.
To have someone put an awl in yours instead, see how our rot and siding repair visits go. Slava has spent 7 years doing this work hands-on, and this is his take on what rot jobs run and why they climb.
What does dry rot repair cost in the Portland area?
Here's the market picture by where the rot sits: Portland-area data from November 2026, a yardstick, not our quote. Mind the basis column: a few rows carry materials and a few are labour alone, so don't add one kind to the other.
| Where the rot is | Basis | Usual spread | Typical job |
|---|---|---|---|
| A window sill or frame | labour only | $300-$1,200 | $600 |
| Door jamb, brickmold or threshold | labour only | $400-$1,600 | $800 |
| Trim, fascia or sill pieces | with materials | $500-$4,000 | $1,500 |
| Fascia plus soffit boards | with materials | $600-$6,000 | $1,800 |
| Rotted siding boards | with materials | $900-$6,500 | $1,800 |
| Deck joists, stairs or railings | with materials | $949-$3,605 | $2,251 |
| Subfloor below a leak | labour only | $500-$3,000 | $1,200 |
Each line is a whole job. Folks look for a square-foot rate, yet a two-inch soft patch can hide a foot of mush under the paint, and the bill tracks what must come apart to reach firm wood. The sill, door and subfloor lines come from hours multiplied by local labour rates, not a published survey, so treat them as the roughest. National and UK sites print other numbers because their wages and weather differ from ours.
Around Cedar Mill, plenty of houses were put up in the 60s and 70s beneath big firs, and that's where trim, fascia and sills tend to go first.
How much does it cost to replace rotted wood trim on a house?
Trim, fascia and sill work spans $500 to $4,000 on the market, materials counted, with $1,500 a typical figure (November 2026) . A lone corner board or one window casing sits near the bottom. Long runs of trim and fascia across two floors sit near the top.
Inside that spread, these move the number:
- piece count and length;
- profile: plain 1x4 or 1x6 goes fast, a milled shape that's out of production doesn't;
- height, ladder or staging;
- missing flashing over the board, which must be fixed or the new wood rots too;
- primer on every side and on the end grain, then paint to match.
Paint is often billed apart. Painting the new trim and fascia runs anywhere between $400 and $2,000 for the labour, around $900 typically, per the same November data . One board still means driving over, setting up and cleaning, so tiny jobs carry a minimum; here's how hourly rates and minimums work .
What does a rotted window sill or door frame cost to fix?
Sill or window frame rot: typically $600, spread $300 to $1,200, labour only (market range, November 2026) . If the sash or the glass seal has gone too, it's a window job; see our window repair page.
Jamb, brickmold or threshold rot: typically $800, spread $400 to $1,600, again for labour alone (same market range) . See our door frame rot service; patching a jamb against fitting a whole new frame has its own guide.
Labour only means the epoxy, fresh wood, primer and any new threshold get added . Doors and windows on the weather side of a west-side house take wind-driven rain, and the low corners of sills and the feet of jambs dry out last.
Why does the price grow once the rotted wood comes off?
Rot is invisible until it's open. It runs with the grain and sits under paint that looks fine, so a first look almost always comes in short. The table below adds no figures; it shows which price line takes over:
| What's soft | What the job becomes | Priced from |
|---|---|---|
| Only the trim, sill or jamb face | carpentry, usually a day or less | sill, door and trim rows |
| Siding boards around it | siding repair | siding row |
| Sheathing or house wrap behind | wall opened, new wrap and flashing | top of the siding row, plus Slava |
| Rim joist, sill plate, studs, posts | framing repair, possibly a permit | not in our data |
| Floor under a leak | subfloor repair | subfloor row (labour only) |
A fair quote fixes a price for what can be seen and names a price for every extra board, foot of trim or framing member found later. Get that line in writing before anyone cuts .
There's no framing figure here because we hold no market row for it . West-side crawl-space houses from the 60s to the 80s can rot at the rim joist under a leaky door or deck ledger, unnoticed until a floor goes spongy.
Can dry rot wood be repaired instead of replaced?
Often, yes. Three routes, each priced differently:
- Harden and fill. Epoxy soaks into a small soft spot, then filler rebuilds the shape. Fits a sill or trim board that's firm everywhere else.
- Splice. Cut out the bad section and glue and fasten a matching piece in, the old Dutchman repair. Common on jambs, sills and corner boards.
- Swap the piece. When rot runs most of the length, or the profile is a stock size, a new board is quicker and lasts longer.
The trim row's own description, "cut out rot, epoxy or replace wood, prime", spans all three, which is part of why it's so wide. Store-bought wood hardener and filler handle small spots that stay dry. Over wood that keeps getting wet they look fine for a season and then let go .
What kills dry rot, and can it go away on its own?
It's all water. Wood rots because it stays damp; take the moisture away and the rot stops spreading, though soft wood never regains its strength . Despite the name, "dry" rot started out wet.
A rot repair that ignores the water gets paid for twice. Usual water fixes, labour only, from the November 2026 market figures:
- caulking and sealing siding gaps and trim joints: about $700, spread $300 to $1,500;
- gutter repair for leaks, sag or hangers: about $350, spread $150 to $800.
Under Cedar Mill's tall trees, fir needles pack gutters and hold water against the fascia. If yours spill over, start with gutter repair. On West Slope's sloped lots, watch where runoff meets the bottom of the walls.
How do you spot dry rot before it gets expensive?
Rot is cheapest while it's a soft corner. Four checks:
- paint bubbling or peeling again and again in one place;
- a screwdriver that sinks in at the foot of a sill, jamb or corner board;
- dark wood cracking across the grain into little cubes;
- caulk lines that have split open.
A walk around the house late in the rainy season, when the wood is wettest, shows the weak spots plainest.
Is a permit required for dry rot repair in Oregon?
Usually not, so most rot jobs carry no permit cost. Oregon's BCD (Building Codes Division) lists repairs with like materials as permit-free unless the work cuts away walls, removes or cuts into a structural beam or something load-bearing, or affects required exits. R105.2.2 in Oregon's 2026 Residential Specialty Code treats ordinary repairs the same way. Portland asks for no permit to fix or replace siding that isn't required to be fire-resistant, though the job must still satisfy the building and zoning rules.
For your budget: trim, sills, jambs and siding boards normally add nothing. A new load-bearing post, beam or framing can add drawings, fees and inspection days. Unsure? Ask the local building department.
Does a pre-1978 house change the price?
It can. The trigger is disturbing more than six square feet of paint in a room, or twenty square feet outside; smaller jobs count as minor repair and maintenance. On a bigger rot job, containment, cleanup and verification add hours and money.
Cedar Hills' 50s-and-60s tracts and much of Cedar Mill predate 1978; Beaverton straddles the line and Bethany is newer. Disturbing lead-based paint is on the list of work we turn down, and how the state's lead rules work has the details .
Who fixes dry rot, and what should a quote show?
Trim, sills, jambs and siding boards are carpentry. Rotted roof sheathing or rafter tails go with the roof work, so if a roofer is on the house, ask whether the bid covers bad sheathing and fascia and at what unit price .
Insurance coverage is for your policy or agent to answer. Insurers often ask what caused the damage and when, so photos help .
Laying two bids side by side, make sure they price the same scope:
- which pieces, by count or linear feet, and how deep each bidder probed;
- a unit price for extra rot found once it's open;
- who deals with the water source;
- whether primer and paint are included;
- the old wood .
Once residential work tops $2,000, Oregon requires the deal in writing, and if a cheaper job climbs over that figure the owner must get a written contract within five days. Siding, soffit and deck-framing repairs often pass that mark once a wall is open; what goes into an Oregon repair contract explains the rest .
If rot showed up on a home inspection or WDO report ahead of a sale, that repair list typically comes to about $2,000, spread $600 to $5,000, labour only (market range, November 2026) .