Signs of Termites in Your House: How to Spot an Infestation

Termites cause billions of dollars in damage to U.S. homes each year, and most of that damage starts quietly. The insects spend their lives inside wood, soil, and the hidden spaces behind walls, so an infestation is usually well established before a homeowner notices anything at all. That is why the signs worth learning are the subtle ones.

This guide walks through the evidence termites leave behind — mud tubes, discarded wings, damaged wood, and swarming insects — how to check your home for them, and when the situation calls for a licensed professional. PestXpertz does not perform pest control; we connect homeowners with independent providers serving their area, subject to availability.

Mud Tubes

Subterranean termites — the most widespread type in the United States — live in the soil and need constant moisture. To travel between their underground colonies and the wood in your home, they build narrow tunnels out of soil, wood particles, and saliva, roughly the width of a pencil. These mud tubes protect them from open air and predators as they cross foundations, piers, crawl space walls, and other exposed surfaces.

• Where to look

  Check the concrete foundation, inside the crawl space, around pipe entrances, and wherever wooden parts of the house sit close to the ground.

• What they look like

  Dry, brown, pencil-width lines running up or across a surface. Break a small section in the middle: a live tube is often repaired within days, while an abandoned one stays open.

• What it means

  Any tube — active or old — is evidence termites have been present. An active tube means the colony is working now and deserves prompt attention.

Swarmers and Discarded Wings

A termite colony is mostly workers and soldiers that never leave the nest. Once or twice a year, usually on a warm day after rain, a mature colony releases winged reproductives called alates, or swarmers. They fly out, mate, and try to start new colonies. Seeing them indoors is one of the clearest signs that a colony is active inside or directly beneath the structure.

• When swarming happens

  Most subterranean termites swarm in spring during daylight hours; drywood termites often swarm in late summer or fall, and some species swarm at night and are drawn to lights.

• Discarded wings

  Swarmer termites shed their wings within minutes of landing, so piles or scattered bits of translucent, equal-length wings on windowsills, in spider webs, or near doors and vents are a strong clue.

• Swarmers versus flying ants

  Termites have straight antennae, a thick waist, and two pairs of wings the same length. Flying ants have bent antennae, a pinched waist, and front wings noticeably longer than the back pair.

A single swarmer found outside near the porch light may simply have flown in from a neighboring property, but swarmers or wings found indoors should be treated as a warning sign and checked promptly.

Damaged and Hollow-Sounding Wood

Subterranean termites eat along the grain, hollowing out the soft springwood and leaving the harder grain in thin layers. From the outside, a board can look intact while its interior is honeycombed with galleries. Common indicators include:

• Hollow sound

  Tap baseboards, door frames, and window sills with a screwdriver handle. Wood that sounds papery or hollow may have galleries behind the surface.

• Blistering or darkening

  Paint or veneer that blisters, dimples, or looks water-stained can mean termites are feeding just beneath it, close to the surface.

• Soft, easily damaged wood

  Wood that gives way under light pressure, or a baseboard that breaks with a crumbly, layered edge, suggests extensive feeding.

• Pinpoint holes

  Small round holes in drywall or wood trim can be exit holes where swarmers left the colony.

Resist the urge to poke at suspected damage repeatedly or tear open walls on your own. Exposing termites can drive them deeper into the structure, and a licensed professional can confirm the extent of activity with far less guesswork.

Conditions That Invite Termites

Termites follow moisture and wood contact, so many infestations trace back to conditions around the house. While walking the exterior, note whether you see:

• Soil, mulch, or dense landscaping touching wooden siding or door frames.
• Wooden porch steps, fence posts, or deck supports in direct ground contact.
• Downspouts, sprinklers, or dripping faucets keeping the foundation or crawl space damp.
• Firewood, lumber, or cardboard stored against or under the house.
• Clogged gutters or poor grading that lets water pool near the foundation.

None of these proves termites are present, but each one raises the odds — and fixing them is worthwhile regardless.

How to Do a Safe Visual Check

You can gather useful evidence without any special equipment:

1. Walk the exterior and look for mud tubes on the foundation, brick, and stucco, and around pipe and utility penetrations.
2. If you have a crawl space, inspect the sill plates, piers, and joists with a bright flashlight where it is safe to do so.
3. Check windowsills, door thresholds, and light fixtures for discarded wings or dead swarmers.
4. Gently tap trim and baseboards along their length and listen for hollow spots.
5. Take photos of anything suspicious — tubes, wings, blistered paint — so a provider can review the conditions before visiting.

Avoid climbing ladders into tight attic or roof spaces on your own, and never break open tubes, walls, or trim to look for live insects. Document what you can see and leave the invasive inspection to a professional.

When to Call a Licensed Pest Professional

Consider professional help if any of the following apply:

• You find a mud tube, especially one that appears repaired after being broken open.
• Swarmers or piles of discarded wings show up inside the home.
• Wood sounds hollow, blisters, or crumbles under light pressure.
• You are buying or selling the home and need a documented termite inspection.
• Your home has known risk factors — wood-soil contact or persistent moisture — and has not been inspected in several years.

Termite treatment is not a do-it-yourself project in most cases: effective treatment depends on correctly identifying the termite species and the full extent of the infestation, and the products involved are generally restricted to licensed applicators. A licensed provider can confirm whether activity is present, recommend an appropriate treatment, and explain monitoring options. Pest control licensing rules vary by state, so it is reasonable to ask a provider for their license details. Learn more about what termite service typically involves on our termite control page.

Sources

• EPA — Termites: How to Identify and Control Them
• UC IPM — Termites Pest Notes
• Texas A&M AgriLife Extension — Termites
• NC State Extension — Termites