Push on the trim around a window or door and your finger sinks in. That soft spot is rot, and it gets worse every time it rains. Wood rot repair is a common fix on homes of every age, and catching it early keeps a small patch from turning into a new window sill, door frame or wall framing. This guide shows you how to spot rotted wood, when epoxy works and when the wood must be replaced, what a good bid includes, and how to keep the rot from coming back.
How to spot wood rot before it spreads
Rot hides under paint until you touch it. Press a screwdriver or your thumb into the low points of the wood: the bottom of window sills, the bottom few inches of door frames, and the ends of trim boards. Healthy wood is hard. Rotted wood is soft, spongy or crumbles.
- Paint that bubbles, cracks or peels in the same spot every year
- Dark stains, or swollen and split wood
- Gaps where caulk has pulled away from the joints
- Fungus, a musty smell, or stains on the inside wall under a window
Where rot starts: sills, door frames, fascia and trim
- Window sills and the bottom of window trim, where rain sits and runs.
- Door frames and thresholds, especially the bottom of the jamb where rain splashes.
- Fascia and soffit behind clogged or overflowing gutters.
- Siding and trim near the ground, mulch or sprinklers.
- Porch posts, railings, deck boards and stairs, where water sits on flat surfaces and end grain.
- Garage door trim, which gets splashed from the driveway.
Why wood rots, and why the water source matters
Wood rot is caused by fungi that feed on wood that stays damp. It starts where water gets in and cannot dry out: failed caulk, cracked paint, unsealed cut ends, overflowing gutters, sprinklers that hit the house, wood touching soil, or a slow leak inside the wall. "Dry rot" is a misleading name, because it needs moisture too; the wood just looks dry once the damage is done.
That is why every good rotted wood repair starts with one question: where is the water coming from? If the leak, the gutter or the missing caulk is not fixed, the new wood will rot too.
Wood rot repair: epoxy vs replace
Epoxy repair: the pro digs out the soft wood, soaks the area with a liquid that hardens the remaining fibers, fills it with an epoxy filler, then shapes, sands, primes and paints it. It works well for small spots in wood that is otherwise sound, and for shaped pieces that are hard to match, like old sills and molded trim.
Replacement: the rotted part is cut out and a new piece is fitted in, or the whole board is replaced. It is the right call when rot is deep, runs along the board, or reaches the framing. New pieces can be primed wood, a rot-resistant wood like cedar, or PVC or composite trim that does not rot.
| What the pro finds | Usual fix |
|---|---|
| A small soft spot, firm wood around it | Harden and fill with epoxy, then prime and paint. |
| Rot at the end of a sill or the bottom of a jamb | Cut out that section and splice in new wood or PVC. |
| Rot through a whole board, sill or jamb | Replace the piece, seal the joints and paint. |
| Soft framing or sheathing behind the trim | Open the wall, repair the framing and stop the leak first. |
Window sill repair and door frame rot repair
Window sills slope outward so water runs off, but paint wears first on that flat surface. Small rot is a good fit for epoxy. Longer rot means a new sill section or a whole new sill. If the window frame or sash is soft too, ask whether repairing or replacing the window makes more sense. Water stains on the inside wall under the window mean water may have gone further.
Door frames rot from the bottom up. A common fix is to cut off the rotted bottom of the jamb and the outside trim and splice in new pieces, often in PVC, while the door stays in place. Ask the pro to check the threshold and the floor just inside the door: a soft floor means the repair is bigger. New weatherstripping, a door sweep and fresh caulk help keep the water out.
Fascia board repair and other roofline rot
The fascia is the board along the roof edge that holds your gutters, and the soffit is the panel under it. They rot when gutters clog and overflow, when the roof edge has no drip edge, or when the roof leaks at the eaves. A typical fascia board repair takes the gutters down, cuts out the rotted boards, checks the rafter ends behind them, puts in new primed boards, paints them and hangs the gutters back.
Some pros cover fascia with metal wrap. That is fine over new, solid wood, but wrapping over rot only hides it. If the roof itself is old or leaking at the edges, read our guide to roof replacement vs repair, and for rotted boards on the walls, see siding repair bids.
What a good wood rot repair bid includes
- Every spot listed, with photos or a marked list
- The method for each spot: epoxy, a section replaced or the whole piece
- The material for new pieces: primed wood, cedar, treated lumber or PVC
- How hidden damage will be handled: if more rot shows up, the price is agreed with you in writing before work continues
- Priming, caulking and painting, and whether the paint will match
- Fixing the water source: caulk, flashing, drip caps or gutter changes
- Lead-safe work if your home was built before 1978 and may have lead paint
- Cleanup, haul-away, the timeline and the workmanship warranty in writing
Ask each pro how far the rot goes, what caused it, and why they chose epoxy or replacement. Ask for proof of insurance and any license your city or state requires, and check it.
Keep wood rot from coming back
- Repaint when paint starts to fail, and re-caulk joints around windows and doors.
- Keep gutters clean and downspouts sending water away from the house.
- Keep mulch and soil a few inches below siding and trim, and trim back plants.
- Point sprinklers away from the walls.
- Check sills, door bottoms, porch posts and fascia once a year, and after big storms.
Paint in good shape is wood's first line of defense, so see our painting bids page if the whole house is due.
Get wood rot repair bids on BidHandyman
Take a few photos up close and from a step back, describe where the rot is and how soft it feels, and post it free. Only pros approved by BidHandyman can bid, and each one has a profile with reviews. Local pros bid to cut out the rot, put in new wood and paint it, and you compare, message and hire the one you like, with no obligation. Post your wood rot repair.