Most San Antonio homeowners discover termites by accident. They're patching a wall, selling the house, or doing a remodel and a screwdriver sinks into wood that should be solid. By then, termites have often been working for months or years. The good news is that subterranean termites, which are the species most common in Bexar County, do leave clues. Knowing what to look for gives you a real chance to catch an infestation early, before the repair bills get serious.
Quick answer
The most common signs of a termite infestation are mud tubes along your foundation or walls, wood that sounds hollow when you tap it, unexplained cracks in drywall, discarded wings near windows, and visible swarmers in spring. Subterranean termites are the dominant species in San Antonio and eat wood from the inside out, so damage is often well underway before homeowners notice anything.
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Spotted something that looks like termite damage? Schedule an inspection with Bob Jenkins Pest & Lawn Services. We've long protected San Antonio homes from termites and we'll tell you exactly what you're dealing with.
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Mud Tubes on the Foundation
Subterranean termites build pencil-width mud tubes to travel between the soil and the wood they're eating. The tubes keep them moist and protected from predators. You'll usually find them running up the exterior foundation, along piers in a crawl space, or up interior walls in a garage or utility room.
If you find a mud tube, break off a short section in the middle and check back in a few days. If termites have rebuilt it, the colony is still active. A dead tube doesn't mean you're in the clear, though. Colonies move and abandon tubes while continuing to eat elsewhere.
Hollow or Damaged Wood
Subterranean termites eat along the grain and leave a thin veneer of paint or wood on the surface while hollowing out the inside. Tap across baseboards, door frames, and structural wood. A dull, papery sound where you'd expect solid resistance is a warning sign worth investigating.
You may also notice doors and windows that suddenly stick, floors that feel slightly springy, or drywall that buckles in a small area. These can have other causes, but in a Texas home that hasn't had a recent termite inspection, each one deserves a closer look.
- Tap baseboards and wall studs and listen for a hollow sound
- Check around window and door frames where wood meets masonry
- Look at the underside of floors, especially near bathrooms or laundry rooms
- Probe any visually damaged or discolored wood with a screwdriver
Swarmers and Discarded Wings
Once a termite colony matures, it sends out swarmers, which are winged reproductive termites that fly out to start new colonies. In San Antonio, swarming typically happens in spring, often after rain, and you may see a cloud of them near a light fixture or window. They look similar to flying ants but have straight antennae, equal-length wings, and a thick waist.
Swarmers don't eat wood. Their job is to mate and nest. But seeing them inside your home almost always means the source colony is inside too. After mating, they shed their wings, so a pile of small wings near a windowsill, door, or vent is just as significant as seeing the swarmers themselves.
Frass and Other Smaller Clues
Drywood termites, which are less common in San Antonio but do occur, push their droppings out of small holes in the wood. The droppings look like tiny pellets or granules, roughly the color of the wood they're eating, and collect in small piles on surfaces below infested wood.
Subterranean termites don't produce frass piles in the same way, but you may notice small piles of soil inside walls, which is material they've brought up while tunneling, or unexplained staining on walls that looks like water damage but has no obvious plumbing source.
Where to Check in a San Antonio Home
Termites follow moisture and wood, so the highest-risk spots in a typical San Antonio home are the exterior foundation perimeter, the garage where wood often contacts concrete, the attic where roof leaks can create damp conditions, and any area with previous water damage. Homes with pier-and-beam construction are inspected from the crawl space, where mud tubes are easy to spot.
Stucco exteriors deserve extra attention. Termites can enter behind stucco with no visible exterior sign, which is one reason San Antonio homes benefit from a professional inspection rather than a DIY walk-around. A trained eye knows where to probe and what to rule out.
What to Do When You Find a Warning Sign
Don't poke aggressively at a suspected area. Disturbing the colony can cause termites to scatter into other parts of the structure. Photograph what you found, note the location, and call a licensed inspector who can assess the full scope.
Bob Jenkins Pest & Lawn Services brings experienced termite specialists to every job. A thorough inspection covers the spots most homeowners miss, and if treatment is needed, we match the method to your home's construction. Catching termites in year one of an infestation versus year four is a significant difference in repair costs.