Identify
Signs of termites in walls
Signs of termites in a finished wall are a hollow tap on the baseboard or window casing, paint that blisters with no plumbing leak, and a small pile of sand-like pellets under a pin-hole in the trim.
Leave the drywall closed. Opening a wall first can wipe the evidence an inspector needs.
Key takeaways
- Tap trim and casings. Hollow or papery sound is a reason to look, not a reason to demo.
- Paint that bubbles on a lower wall with no leak can sit over feeding in the stud.
- A sand pile under a hole smaller than 2 mm is drywood frass. Six-sided pellets confirm.
- Bits of soil around a tiny hole in plaster point to subterranean work, not a nail pop.
- Do not spray into a wall void and call it a treatment.
You will not see a pencil tube on painted drywall. The colony is in the dark. What you get is sound, paint, and a little debris at the base of the trim.
Tap the trim. Leave the wall.
Walk the first-floor baseboards and window casings with a knuckle or a screwdriver handle. Solid wood thuds. Infested wood sounds empty. Kentucky notes that the outer face often stays intact while the inside is mined, which is why a vacuum head once went through a baseboard that still looked painted.
A blister of paint with no dripping pipe is worth a closer look. Water from a leak spreads from a source. Termite blistering often follows a stud line. Kentucky also flags tiny holes through drywall or plaster with bits of soil at the edge.
Do not tear out finished walls to “see.” You can destroy the map and still miss the colony.
Sand under a pin-hole
UC IPM puts drywood termites inside the lumber, not in the soil. They push pellets out through a kick-out hole smaller than 2 mm. The pellets have six sides. Sweep the pile, wait a few days, and look again. New pellets mean the gallery is still in use. Building vibration can shake a few old ones loose, so one pile is a clue, not a close.
A coarse, stringy dump with insect parts in it is carpenter-ant frass, not drywood sand.
Mud tubes belong on the foundation and in the crawl. If you find one indoors along a baseboard, photograph it and leave it. Consumer spray in a tube does not reach the colony in the soil.
Log the room and a photo in the sighting log before anyone patches paint. Read termite treatment cost after a licensed look. Contact for a referral path. Typical US ranges, not a bid.