Where rot shows up
Rot starts where water sits: horizontal surfaces, end grain and joints that lost their caulk. Walk the house with a screwdriver and press gently. Sound wood resists; rotted wood is soft, spongy or crumbles.
- Window sills and the bottom corners of window trim
- Fascia boards, especially at ends and behind gutters
- Bottoms of door casings and garage door jambs near the ground
- Siding bottoms close to soil, sprinklers or roof runoff
- Deck ledgers, railings and posts where they meet the house
Epoxy vs. replacing the wood
| Consolidate + epoxy | Cut out + replace | |
|---|---|---|
| Best for | Small, shallow damage in otherwise sound trim | Deep, widespread or structural rot |
| How it works | Remove punky wood, harden what remains with consolidant, fill and shape with epoxy | Cut back to sound wood, splice or replace the piece, prime all sides |
| Upside | Saves trim with a profile that is hard to match | Removes the problem completely |
| Watch for | Used over deep rot, it hides a problem that keeps growing | Costs more; profile and joints have to be matched |
Why paint fails over rot
Decay fungi need moisture. Once wood is soft, it absorbs water, swells and shrinks, and pushes paint off from behind. A coat of paint over it looks fine for a season, then peels at the same spot. That's why a good exterior quote lists repairs separately, with locations, before the painting scope.
Termite reports: Section 1 and Section 2
A wood-destroying pests and organisms report, common when a home is sold, separates findings into Section 1 (active infestation or infection, such as fungus damage, or damage resulting from it) and Section 2 (conditions likely to lead to infestation or infection, like excess moisture). Buyers and sellers often negotiate who pays for which.
Who does the repair?
Many painting contractors handle routine trim and sill repairs as part of prep; others bring in a carpenter. Either way, the repair should be described in the written quote: location, method (epoxy or replacement), and how it will be primed. Check the contractor's license on the CSLB site and confirm it covers the work in the contract.
Next: exterior painting · what it costs · choosing a painter
Questions homeowners ask
Can you just paint over dry rot?
No. Paint can't hold soft, decayed wood together, and the rot keeps spreading under the new coat. Damaged wood has to be consolidated and filled, or cut out and replaced, then primed before painting.
Is epoxy repair as good as replacing the wood?
For small, shallow damage at sill corners and trim ends, a consolidant plus epoxy filler can be a durable repair and saves removing trim. When rot is deep, widespread or structural, replacing the section is the better fix.
My pest report lists dry rot. Who should repair it?
Talk to the company that wrote the report first. It can tell you what it needs to see to clear the item, and whether it will re-inspect someone else's repair. Then decide who does the carpentry.
Sources
- California Structural Pest Control Board state
- CSLB: check a license state
- Barbour Painting (Concord): Bay Area painting prices contractor pricing
Contractor price pages are published pricing from individual painting companies, not quotes. Your price can land below or above these ranges.