Termites in Walls: Signs, Sounds, and How They Are Treated
Most termite work happens where you cannot see it, inside the wall. Here is what shows through, what you might hear, and what treatment through a wall actually involves.
Termites in a wall show up on the surface before you ever see a termite: tiny kickout holes with pellets piling up below them (drywood), small dried-mud spots or a mud tube climbing out of the baseboard (subterranean), paint that blisters or ripples, wood or drywall that sounds hollow or gives when pressed, and swarmers coming out of a crack. Termites do make sounds, but faint ones: soldiers bang their heads against the gallery walls to raise an alarm, and workers chewing make a soft rustle. Most people never hear them, and anything loud enough to wake you is almost always rodents. Termites are active around the clock inside the wood. Treatment through a wall usually means small drilled holes and foam or liquid placed into the galleries for drywood termites, bait stations and a targeted soil treatment for subterranean termites, and fumigation when drywood activity is widespread or hidden.
Local help: Found pellets, mud or wings? Text a photo to (626) 409-1584 and we will tell you what it is and whether it needs an inspection. Quotes from photos are free.
On this page
- Signs of termites in walls, at a glance
- Drywood termites in walls: pellets and pinholes
- Subterranean termites in walls: mud where mud should not be
- Can you hear termites in the walls?
- Are termites nocturnal?
- What not to do when you find termites in a wall
- How to get rid of termites in walls
- Sources
- Quick answers
Signs of termites in walls, at a glance
| What you notice | What it usually means | Which termite |
|---|---|---|
| Tiny round holes (smaller than 2 mm) with hard, six-sided pellets piling up below | An active drywood colony pushing pellets out of the wood behind the wall | Drywood |
| Small spots of dried mud on the wall or trim | Termites sealed a hole they cut to the surface; a sign of activity inside | Subterranean (sometimes drywood) |
| A pencil-width mud tube climbing out of a baseboard, slab edge or foundation | Subterranean termites traveling from the soil into the wall | Subterranean |
| Paint that blisters, bubbles or ripples; faint sunken, winding lines under paint or wallpaper | Galleries just beneath the surface; sometimes moisture instead | Either |
| Trim, framing or drywall that sounds hollow when tapped or gives under a screwdriver | Wood eaten from the inside, thin at the surface | Either |
| Swarmers or piles of identical shed wings coming out of a crack, frame or outlet | A mature colony inside the structure | Either |
| Faint clicking or rustling in a quiet room | Possibly soldiers or feeding workers; confirm with the signs above | Either |
| Scratching, scurrying or thumping, mostly at night | Rodents, not termites | Not termites |
Drywood termites in walls: pellets and pinholes
Drywood termites live entirely inside the wood, so a colony in a wall is in the studs, the plate, the window and door framing or the trim, and it stays there. What reaches the room is its housekeeping: the termites push their fecal pellets out through tiny kickout holes, smaller than 2 millimeters, and the pellets pile up on the sill, the floor or the baseboard below. The University of California calls the six-sided pellets diagnostic for drywood termites. Fresh piles that reappear a few days after you clean them up mean the colony is active; a few grains can just be building vibration.
Because colonies are small and widely dispersed, a house can have several in different walls, and the University of California notes that wall coverings make it hard to judge how far an infestation extends. That uncertainty is why an inspector sounds and probes the wood rather than guessing from one hole, and why widespread activity sometimes calls for fumigation. More on the termite itself: the western drywood termite.
Subterranean termites in walls: mud where mud should not be
Subterranean termites come up from the soil, so their sign in a wall is dirt. They travel in pencil-width mud tubes that climb the foundation, a pier or the edge of a slab and run up behind the baseboard, and when they accidentally cut through to the room they plug the hole with mud, leaving a small dried spot on the wall. Galleries that run just under paint or wallpaper can show as faint sunken, winding lines. The University of California notes that damaged wood is often thin at the surface and easily punctured with a knife or screwdriver, and that damaged areas can darken or blister.
Stucco deserves a special note: where stucco runs down into the soil, termites can travel between the stucco and the foundation unseen, which is why inspectors pay attention to that line and why we pull soil back from it. Our subterranean termite treatment page covers what a mud tube means.
Can you hear termites in the walls?
Rarely, and this is the question we get asked most about walls. Termites do make sounds. Soldiers bang their heads against the gallery walls to raise an alarm, a behavior researchers at the University of Mississippi filmed with high-speed cameras; the colony feels the vibration through organs on its legs rather than hearing it. Feeding workers make a faint rustle or click. Both are very quiet, and hearing them through a finished wall usually takes a very quiet room and some luck. Pipes, settling wood and other insects make similar faint noises.
What people actually hear at night, scratching, scurrying, thumping, is rodents. If that is your sound, start with scratching noises in the walls at night. If it is faint clicking and you are not sure, look for the visible signs above; they are far more reliable than your ears.
Are termites nocturnal?
Termites are not nocturnal the way rats are. They live sealed inside wood or soil and work around the clock, year-round, which is how a colony can feed on a wall for years without being noticed. The termites you do see in daylight are swarmers, the winged reproductives that fly on warm days; our flying termites guide covers when a few matter.
What not to do when you find termites in a wall
- Don’t spray into the hole. Store products don’t reach the galleries, and spraying swarmers destroys the evidence an inspector needs (what DIY can and can’t do).
- Don’t scrape off the mud. The tubes and spots are a map of where the colony enters. Photograph them.
- Don’t open the wall yet. Treatment rarely needs it, and tearing out drywall before an inspection can scatter the evidence.
- Do the pellet test. Clean up the pellets, mark the spot, and look again in a few days. A fresh pile means active termites.
How to get rid of termites in walls
Drywood termites in a wall are usually handled with localized treatment: small holes drilled into the infested wood or the wall void, foam or liquid placed directly into the galleries, and the holes patched afterward. One visit, you stay home, and the work carries a two-year written warranty. The University of California notes that localized treatment works well when the colony is located and the treatment reaches it, and that no one can be sure a localized treatment caught every colony in a house, which is why we inspect the whole structure first and say honestly when activity is too widespread or hidden for anything but fumigation.
Subterranean termites in a wall are not treated in the wall. The colony is in the soil, so the work is in-ground bait stations around the house plus a targeted non-repellent treatment at the confirmed entry point, and fixing the moisture that fed it. The tube in the wall stops being rebuilt once the colony is dealt with.
Either way, the first step is a termite inspection that sounds and probes the wood, checks the attic and crawlspace, and puts the findings in writing. Text a photo of the hole, the mud or the pellets to (626) 409-1584 for a free read.
Sources
Common Questions
Quick Answers.
What are the signs of termites in walls?
Tiny holes with pellets piling up below them, small dried-mud spots on the wall, a mud tube coming up from the baseboard, paint that blisters or ripples, drywall or trim that sounds hollow or gives when pressed, and swarmers or shed wings coming out of a crack in the wall or frame.
Can you hear termites in the walls?
Rarely. Soldier termites bang their heads against the gallery walls to alarm the colony, and workers chewing make a faint rustle, but both are very quiet. Scratching, scurrying or thumping loud enough to notice at night is almost always rats or mice.
Do termites make noise?
Yes, but faintly. Researchers have filmed soldier termites head-banging to send vibration alarms through the colony, and feeding workers make a soft clicking or rustling. Hearing it through a finished wall is unusual; the visible signs are far more reliable.
Are termites nocturnal?
Not in the way rodents are. Termites live inside wood or soil and work around the clock; they are not out at night and hiding by day. The termites you see in daylight are swarmers, which fly on warm days.
What does termite damage in drywall look like?
Drywall itself is not food, but termites tunnel through its paper facing and the wood behind it. From the room you may see tiny pinholes, small spots of dried mud, faint sunken or winding lines under the paint, blistering, and pellets or mud at the base of the wall.
How do you treat termites inside a wall?
For drywood termites, small holes are drilled into the infested wood or wall void and foam or liquid is placed directly into the galleries; the holes are patched afterward. For subterranean termites, the colony is treated in the soil with bait stations plus targeted treatment at the point of entry. Widespread or hidden drywood activity may call for fumigation.
Do I need to open the wall to get rid of termites?
Usually not. Localized treatment reaches the galleries through small drilled holes, and an inspector can tell a lot from the surface signs and by sounding and probing the wood. Opening the wall is sometimes needed to judge or repair damage, not to treat.
Can termites be in a stucco or plaster wall?
Yes. Termites eat the wood framing and lath behind stucco or plaster, not the plaster itself. Subterranean termites can also travel unseen between stucco and the foundation where the stucco runs down into the soil, which is one reason inspectors look at that line.
Should I spray termites coming out of a wall?
No. Spraying kills a few swarmers and destroys the evidence that tells an inspector which termite you have and where the colony is. Bag a few, photograph the spot, and get an inspection.
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About the Author
Joshua A. Westad is the owner and licensed operator of ExterMetro Termite and Pest Control in Arcadia, CA. He holds California SPCB Company Registration #8828 (Branch 2 & 3), is a licensed WDO inspector, and has worked San Gabriel Valley homes and businesses for over twelve years — hands-on in the field on every kind of job the valley throws at him.
Think you just found termite evidence?
Bag a few wings or pellets, snap a photo, and text it to (626) 409-1584 — quotes from photos are free, and your job stays under licensed ExterMetro oversight from inspection through follow-up.