What do termites look like?
A worker termite is pale cream to white, soft-bodied, and small — a subterranean worker is about 1/8 inch (3mm), and drywood workers run larger, up to around 3/8 inch. The body runs straight from head to tail with no pinch in the middle, and the antennae come straight out of the head in a string of tiny beads.
Most people never see a worker. They avoid light and stay inside wood or soil, which is the whole reason termite damage is usually found long after it started. The termite you are most likely to actually see is a swarmer — darker, winged, and out in the open because it is looking for somewhere to start a new colony.
The six signs of an infestation
These are the six things worth looking for, in roughly the order people tend to notice them.
| Sign | What it looks like | What it points to |
|---|---|---|
| Mud tubes | Pencil-width earth tunnels running up foundations, piers or joists | Strongly suggests subterranean termites |
| Discarded wings | Small piles of identical translucent wings on sills and near lights | A swarm has happened, often indoors |
| Frass | Gritty pellets like coarse sand or pepper, below pen-tip holes | Drywood termites |
| Hollow wood | Timber that sounds papery when tapped, sound surface | Feeding inside, any type |
| Sticking doors | Doors and windows suddenly tight or out of square | Damaged frames, or the moisture behind it |
| Blistered paint | Bubbling or peeling that looks like water damage | Galleries just under the surface |
The first three are close to diagnostic on their own. The last two are not — sticking doors and blistered paint each have a dozen innocent explanations, and they only mean much alongside something from the top of the list.
Two signs together make an infestation very likely, and the pairing narrows down which kind you have — see drywood versus subterranean.
Where to look
Termites work in the dark, in damp, undisturbed places. Searching those first finds them far more often than walking the yard in daylight.
Start low and outside, then move in and up:
| Where | What to look for |
|---|---|
| Foundation walls | Mud tubes, especially on the shaded side. Take a flashlight — tubes on bare concrete are close to the same color as the wall |
| Crawl space or basement | Tubes on piers and the underside of floor joists; soft spots in the subfloor |
| Window and door frames | Discarded wings on sills, blistered paint, frames that have gone out of square |
| Baseboards and floors | A papery sound when tapped; floors that feel spongy underfoot |
| Attic and roof timbers | Pellets on the floor below beams — drywood territory, since no soil is needed up there |
| Outside the house | Fence posts, deck framing, old stumps, and any firewood stacked against a wall |
Termites or flying ants?
This is the question people ask most, and there is a reliable answer: look at the waist, the antennae and the wings. All three differ, and none of them requires an expert eye.
A termite has no waist — the body is one continuous width. An ant is pinched sharply in the middle. Termite antennae run straight out in small beads; ant antennae bend at an elbow. And a termite's four wings are all the same length and clearly longer than its body, where an ant's front wings are noticeably longer than the rear pair.
The full comparison, including when each one swarms and what the discarded wings tell you, is on the termite swarmers page.
Mud tubes, and why they matter most
Of all six signs, mud tubes are the most conclusive. Nothing else builds them: they are tunnels of soil, saliva and droppings that subterranean termites construct so they can travel between the ground and the wood they are eating without ever being exposed to open air.
They are about the width of a pencil, brown, and usually run vertically up a foundation wall, a pier, or the inside of a crawl space. Finding one means termites have already built a route into the structure.
There is a simple test for whether it is still in use. Break a short section out of the middle of one tube, leave the rest alone, and look again in two or three days. Sealed over with fresh soil means the colony is using that route now.
Break one section only. Knocking down every tube scatters the colony and destroys the trail an inspector would follow back to the entry point. There is more on reading them — including what they are not — on the mud tubes page.
What termite damage actually looks like
Termites eat wood from the inside out, following the softer growth rings and leaving a thin outer shell intact. That is why damage is so often described as sudden — the surface looks normal until the moment it gives way.
Tap suspect timber with the handle of a screwdriver. Sound wood answers with a solid knock; hollowed wood sounds papery and slightly dull. If the tool breaks through, you have found galleries rather than made them.
The galleries themselves differ by species. Subterranean termites line theirs with soil and leave them dirty; drywood termites keep theirs clean and smooth and push their droppings out of the wood entirely.
What brings them to a house
Moisture and wood touching soil, more than anything else. The conditions that invite termites are ordinary maintenance problems:
Water where it should not be
Leaking pipes and taps, blocked gutters discharging against the wall, air-conditioning condensate, and damp crawl spaces with no ventilation. Subterranean termites need moisture constantly and will follow it.
A bridge from soil to timber
Firewood stacked against the house, timber form boards left in place after construction, fence posts touching siding, and mulch or garden beds banked up over the foundation line.
Wood already softened
Decayed sills, water-damaged subfloor and old stumps left in the ground. Fungal decay makes timber easier to eat and often precedes the termites rather than following them.
What to do if you find them
Confirm first, then leave them alone, then call someone. In that order, and the middle step matters more than it sounds.
Do not spray, disturb or break open anything else beyond that single tube test. Subterranean colonies respond to disturbance by abandoning the area and re-routing, which does not remove them — it removes your evidence and makes the infestation harder to trace.
Photograph what you found. A clear picture of a mud tube, a wing pile or frass is worth more to whoever inspects than a description, and it records what the site looked like before anything moved.
What an inspection and treatment involve
Being told to call a professional is easier to act on when you know roughly what you are calling for.
An inspection is mostly looking, and it takes an hour or two on an average house. The inspector goes through the crawl space or basement, sounds accessible timber, works around the outside at ground level, and checks the attic. Some use a moisture meter, since termites and damp travel together. What you should get at the end is a written report saying what was found, where, and what type.
Treatment then depends entirely on which type it is, which is why the distinction on this page matters:
| Approach | What it does | Used for |
|---|---|---|
| Liquid barrier | Treated soil around and under the structure, so termites cannot cross it | Subterranean |
| Baiting | Stations in the ground that workers carry back, aimed at the colony rather than the individuals | Subterranean |
| Localized wood treatment | Applied into the infested timber itself | Drywood, where the infestation is contained |
| Fumigation | The whole structure tented and gassed | Drywood that has spread beyond a few pieces |
Which of these is appropriate is a judgement about your building, not something this page can make for you. The point of listing them is so the recommendation you get is one you can ask questions about.
When it stops being a DIY job
Identification is something you can do yourself, and this page plus a photo will usually get you to the right answer. Treatment generally is not.
The reason is structural: a subterranean colony lives in the soil and can reach well beyond the walls of the house, so the termites in your wall are a fraction of the problem. Surface treatment kills what it touches and leaves the colony feeding. That is why DIY treatment so reliably appears to work and then does not.
Drywood infestations are sometimes more contained, and a single infested piece of furniture can genuinely be dealt with by replacing it. A drywood colony inside structural timber is not in that category.