A painted baseboard can look perfectly sound until a screwdriver passes through it with almost no pressure. That is often how homeowners first learn how to diagnose termite damage: not from a dramatic collapse, but from a small soft spot around a window, door jamb, fascia board, or exterior trim.
On older homes across Mar Vista, Santa Monica, Venice, and the Westside, termite damage is frequently hidden under paint, patching, or layers of prior repair. The goal is not to poke holes in every piece of wood. It is to recognize the signs, understand how far the damage may extend, and avoid covering up a condition that will continue to weaken the house.
Start by separating termite evidence from wood rot
Termites and moisture damage often appear in the same places, and they can exist together. A leaking gutter, failed window seal, or unprotected exterior joint softens wood and creates favorable conditions for termites. But the repair approach changes depending on what is active and what is old damage.
Drywood termites are common in Los Angeles. They live inside the wood they consume and may leave small, hard pellets called frass below a wall, window, door, or ceiling area. These pellets resemble tiny grains of sand or pepper. They are not sawdust. If fresh pellets keep appearing after you clean them up, there may be an active infestation nearby.
Subterranean termites usually travel from the ground through sheltered mud tubes. Look along the foundation, crawl-space walls, garage edges, plumbing penetrations, and lower exterior framing. A pencil-width mud tube is a reason to call a licensed pest-control inspector, even if the wood itself still feels solid.
Rot, on the other hand, is usually tied to repeated moisture exposure. The wood may be dark, soft, cracked, or fibrous, especially at the bottom of door jambs, beneath window sills, on fascia boards, and where stucco or soil meets wood. Rot does not produce termite pellets or mud tubes. Still, a carpenter should treat both conditions seriously because weakened wood cannot reliably hold fasteners, weather seals, or door hardware.
How to diagnose termite damage without causing more damage
I begin with the pattern, not a random probe. Termite damage rarely respects the visible edge of a board. A small blister in paint can be connected to hollow framing or trim several inches away.
Look for paint that no longer matches the wood beneath it
Paint that bubbles, lifts, or develops an unusual rippled texture can mean moisture, but it can also mean termites have eaten channels just beneath the surface. Termites often leave a thin painted skin intact while removing much of the wood behind it. Press lightly with a finger or the handle of a screwdriver. Sound wood feels firm. Damaged wood may flex, crush, or sound hollow.
Pay particular attention to exterior trim where the bottom edge meets a horizontal sill or stucco. That joint holds water if it was not properly sloped, caulked, or painted. On a wood window, inspect the sill ends, stool, casing bottoms, and the lower portions of the jamb. On doors, check the jamb legs, threshold area, brick molding, and the lower corners of the door itself.
Check for small holes, galleries, and pellets
A few small holes do not prove termite activity. Old nail holes, insect exit holes, and previous repairs can look similar. What matters is the combination of signs: small openings, hollow-sounding wood, loose paint, fresh frass, and visible channels inside exposed wood.
Termite galleries are irregular tunnels. The wood may look layered or honeycombed, with thin sections left behind. Rot tends to break down more uniformly, becoming soft and crumbly. If you expose suspicious wood during a repair, photograph it before removing it. A pest inspector may need to see the condition, particularly when there is a question about active termites.
Test trim and framing carefully
A thin awl or screwdriver can help, but use it selectively. Probe the least visible edge first, such as the underside of a sill or back edge of exterior trim. The tool should resist firm hand pressure in sound wood. If it sinks deeply, pulls out dry damaged fibers, or enters an empty void, the condition needs further evaluation.
Do not use this test on every painted surface. Excess probing creates unnecessary finish damage and can open a path for water. I would rather remove one compromised piece of trim cleanly and inspect the framing behind it than leave a row of exploratory holes across an original door casing.
Inspect the places termites exploit first
Termites do not need a whole house to be neglected. One leaking joint or unpainted cut edge can be enough to start a localized repair that grows larger than expected.
On the exterior, inspect fascia boards behind gutters, rafter tails, eaves, window trim, garage-door trim, wood siding, deck connections, fence attachments, and any wood close to soil. Gutter overflow is a common culprit. Water repeatedly running behind a gutter can damage fascia from the back, leaving the painted front looking acceptable until the board no longer has strength.
Inside, look at baseboards near exterior walls, window and door casings, areas below bathrooms or kitchens, hardwood flooring near plumbing, and ceilings beneath roof penetrations. A sticking door can be a simple hinge issue, seasonal movement, or swollen paint. But if the jamb feels soft, the hinges pull loose, or the strike plate no longer holds because the wood has failed, termite or moisture damage should be considered.
Older solid-wood doors deserve a careful diagnosis. Replacing a door because the jamb has termite damage is often unnecessary. If the door is sound, I can preserve it while rebuilding the damaged jamb section, restoring weather protection, and fitting the door correctly. The hidden work matters: framing needs to be solid, the jamb needs to be plumb, the threshold needs the right slope, and the exterior joints need to shed water rather than trap it.
Determine whether the damage is active before repairing it
A handyman or carpenter can identify failed wood and repair it, but a licensed termite professional is the right person to determine whether termites are active and recommend treatment. That order matters. Installing new trim over an active infestation may improve the appearance while leaving the underlying problem untouched.
If you see fresh frass, mud tubes, live insects, or damage spreading in more than one area, schedule a termite inspection before opening up and rebuilding the affected work. Ask the inspector to identify the termite type, whether activity is current, and the treatment area. Keep the report. It gives the repair work a clear starting point.
Sometimes the inspection confirms old termite damage with no active infestation. In that case, repair decisions depend on structural importance and the condition of surrounding wood. A lightly tunneled piece of decorative trim may be removable and replaceable without much disruption. A damaged header, wall stud, floor joist, or door framing member requires a more deliberate repair plan. The goal is to remove wood that has lost its strength, preserve what remains sound, and reconnect the assembly so doors, windows, siding, and finishes work as intended.
Do not let a cosmetic patch hide a water problem
Termite repair is also weatherproofing repair. If the original failure was a leaking sill, missing flashing, cracked caulk, overflowing gutter, or paint breakdown, replacing damaged wood alone will not hold up.
Before I install replacement wood, I look for the source of moisture. That may mean correcting a gutter pitch, rebuilding a sill with a drip edge, sealing end grain, improving a threshold transition, or removing failed caulk and applying the right sealant to a properly prepared surface. Exterior repairs need paintable, compatible materials and drainage details that match the location. Bathroom or wet-area repairs have different needs.
This is where a quick patch can become expensive. Wood filler is useful for small, stable defects after the cause is corrected. It is not a substitute for a missing section of structural jamb, a hollow fascia board, or framing that no longer holds screws. If a repair needs backing, fastening, flashing, sealing, priming, and finish coats, skipping one step usually shows up later as a cracked joint or recurring soft spot.
When to call for help
Call a pest professional promptly when you find fresh pellets, mud tubes, live termites, or widespread suspicious damage. Call a qualified repair professional after treatment is complete, or when an inspection confirms inactive damage that needs rebuilding. If a door opening, window frame, roof edge, or floor feels loose or unsafe, do not wait for the next repaint.
For Westside homes, I often find that the best repair is not wholesale replacement. Original wood windows, detailed casing, and solid doors can often be saved when the damage is isolated and the moisture path is corrected. The useful next step is simple: document what you see, get active termites ruled out, and repair the wood in a way that keeps water and insects from finding the same opening again.


