Signs of Termites: What to Look For and Where to Check

Termites rarely show themselves. They stay inside soil, wood and the mud tunnels they build, so most people find out from a swarm, a line of mud on the foundation or damage uncovered during a repair. This guide covers each sign, how to inspect your own home and what to do if you find something. For an overview of termite types and prevention, start with the main termites guide.

Swarmers and discarded wings

Swarmers are the winged adults that leave a mature colony to start new ones. They are often the first sign people notice.

• What you see: dark, winged insects about the size of a small ant, flying out of walls, floors or window frames, or crawling toward light. Afterward, you find small piles of shed wings on windowsills, in spider webs or near doors and light fixtures.
• What it means: swarmers inside the house almost always point to an active infestation that needs treatment. Swarmers seen around a stump or woodpile in the yard do not necessarily mean the house is infested, but swarms next to the foundation or a porch are more concerning.
• Are they harmful? No. Swarmers cannot damage wood and live only about a day. Vacuum them up.

Timing depends on the species and where you live:

A heated basement can trigger a swarm indoors in winter. Swarming ants often appear at the same time of year, so check the insect before you assume termites. The termites vs flying ants table shows the differences.

Mud tubes

Subterranean termites need to stay protected and moist, so they build mud shelter tubes to cross anything that is not soil or wood: concrete, brick, block, metal and pipes. You find them on foundation walls, piers, sill plates, joists, crawl space supports and around utility openings.

To check if a tube is active, break a small section and look for creamy white worker termites. An empty tube does not prove the colony is gone. Termites often abandon one section and keep feeding somewhere else. Mark the spot and check again in a week or two to see if they rebuilt it.

Damaged wood

Termite damage is often hidden behind paint, drywall or flooring. Signs to watch for:

• Layered, hollowed wood. Subterranean termites eat along the grain and leave the harder growth rings, so damaged wood looks layered.
• Galleries lined with soil. Subterranean termite tunnels are lined or packed with mud and soil. Moisture damage and carpenter ant damage do not look like this.
• Hollow-sounding wood. Tap or probe wood with a screwdriver or the handle of a hammer. Damaged wood sounds dull and gives way easily.
• Blistering or rippled surfaces. Paint that bubbles, wood that looks darkened or blistered, and rippled wall coverings can mean termites are feeding just below the surface.
• Small holes in drywall or plaster. Tiny holes can show up where termites are feeding behind the surface.

Drywood termite pellets

Drywood termites do not build mud tubes and do not need soil. Their clearest sign is their droppings. They push dry fecal pellets out of small kickout holes, which builds into piles on floors, windowsills or furniture below.

• Pellets are tiny, hard and have six flattened sides. You can see the shape with a hand lens.
• Kickout holes are very small, under 2 mm (less than 1/16 inch) across.

A pile of pellets alone does not prove the termites are still active, because vibration can shake old pellets loose. Sweep the pile up and check the spot again over the next few days. New pellets mean an active colony.

How to inspect your home

For a first look on your own, you need a strong flashlight, a flathead screwdriver, a hand lens or phone camera and old clothes for the crawl space.

1. Walk the outside. Look at the foundation from soil level up for mud tubes, especially behind shrubs, under porches and steps, near air conditioning units and where pipes enter.
2. Check wood near the ground. Probe sill plates, door frames, deck posts, fence posts and trim near soil or mulch with the screwdriver.
3. Look for moisture problems. Note leaky gutters, downspouts dumping water at the foundation and soil sloping toward the house. Termites follow moisture.
4. Check the crawl space or basement. Shine the light along foundation walls, piers, joists, sill plates and around plumbing and heating units. Look for tubes, soft wood and shed wings.
5. Check inside. Look at windowsills and floors near doors for wings or pellets. Look at baseboards and window frames, and pay extra attention to bathrooms, kitchens and laundry rooms where leaks happen.
6. Check the garage and attached structures. Garages, porches and slab additions often have expansion joints and wood close to soil.
7. Write it down. Photograph anything suspicious and note where you found it.

Your own inspection cannot rule out termites. Many infestations sit inside walls, under slabs or under flooring where you cannot see. A licensed inspector knows where to look and how to read the signs.

What to do if you find signs

Do not tear up the evidence. Leave mud tubes and damaged wood mostly in place and do not spray them. An inspector uses them to confirm the type of termite, judge how active they are and decide where to treat.

1. Collect a sample. Put a few insects or wings in a small jar or zipper bag. Save some pellets in a bag if you suspect drywood termites.
2. Take photos of tubes, damage and pellets, with something in the frame for scale.
3. Get it identified. Your local cooperative extension office or a licensed pest control company can confirm what you found.
4. Get more than one inspection. Two or three inspections help confirm the problem and let you compare treatment plans and warranties. Termites damage wood slowly, so a few extra days rarely matter. See how to choose a pest control company.
5. Fix moisture problems now. Repairs to leaks and drainage help no matter which treatment you pick.

Once termites are confirmed, the termite treatment options guide explains how soil treatments, baits, spot treatments and fumigation compare.

What is not termites

Several other wood pests get mistaken for termites. Here is how to tell them apart.

If you think you have carpenter ants or another ant, the ant control guide covers what to do. Look-alike beetles are common too, so a definite ID for powderpost beetles usually takes an entomologist or a pest control professional.

Termite sign questions

I found wings but no termites. Is that a problem? It can be. Swarmers shed their wings within minutes of flying. A pile of wings indoors, especially near a window or door, is a reason to schedule an inspection.

How long can termites go unnoticed? Subterranean colonies grow slowly at first, and an infestation can go unnoticed for anywhere from one to eight years. That is why regular inspections help.

Does a past treatment mean I am protected? Not forever. Liquid soil treatments are meant to last at least five years when applied by the label, not indefinitely. Keep looking for new signs, and keep any service contract renewed if you have one.