San Antonio's soil is a big part of its termite story. Expansive clay swells with rain and shrinks in drought, and over time those cycles crack slabs and open hairline paths to the wood above. Combined with warm weather that lasts most of the year, that makes subterranean termites a steady concern for San Antonio homeowners.
What lives in the soil here
Native subterranean termites are the primary species across Bexar County. They live in colonies underground, send out mud tubes along foundation walls and enter through cracks, plumbing penetrations and the expansion joints in slabs. Drywood termites occur in smaller numbers and may show up in older wooden elements such as fascia and furniture. Formosan termites have been reported in other parts of Texas, so a proper identification by an inspector is worthwhile if you find unusually large swarms.
Which houses are most exposed
Most San Antonio houses were built on slabs, so there is no crawl space to check. Brick veneer, popular across neighborhoods like Alamo Heights, Olmos Park and Castle Hills, hides the foundation line where termites often enter. Older homes in Monte Vista, Tobin Hill and Dignowity Hill sometimes have pier-and-beam foundations, which give termites a crawl space and shaded wood to work with. Newer homes in the northern suburbs and near Helotes may have landscaping beds and sprinkler systems that keep soil moist at the slab edge.
Warning signs
- Swarms of winged termites around windows or lights after warm, humid weather.
- Mud tubes on foundation walls, in the garage, or running along piers.
- Doors or windows that begin to stick for no clear reason.
- Blistering or bubbling paint, and floors that feel slightly soft.
- Discarded wings on sills.
How treatment works
A licensed inspector examines the garage, attic, slab edges, plumbing penetrations, and areas under porches and decks. Subterranean termites are generally treated with a liquid barrier around the foundation or a baiting system. On slab homes, technicians may drill through patios or garage floors where soil is covered. Texas regulates structural pest work, so providers must be licensed and are expected to follow state requirements for documentation.
After treatment, follow-up inspections help catch new activity. Moisture control is part of the solution, because a leak that wets wood can invite a fresh colony.
Prevention
- Keep soil, mulch and flower beds below the slab edge and away from siding.
- Repair leaking plumbing, AC drain lines and irrigation heads near the foundation.
- Direct gutters and downspouts away from the house.
- Remove tree stumps, old fence posts and buried scrap wood near the home.
- Keep firewood stacked off the ground and away from walls.
Who to call
PestMinistry is a referral service, not a termite company. Call (844) 725-1661 and we will connect you with an independent licensed provider in our network who handles termite control in San Antonio. The provider inspects and treats, and explains the plan to you directly.
Termite questions in San Antonio
Does drought stop termites?
Not entirely. They go deeper for moisture and are drawn to irrigated beds and leaks.
Can a brick home get termites?
Yes. Termites travel behind brick veneer and enter wood framing through slab gaps.
When do swarms occur?
Often in spring and again after fall rains, usually on warm, humid days.
How often should I have an inspection?
Annual checks are common in Texas. Your provider can recommend a schedule.