Termites can and do damage drywall, but not in the way most people expect. They don’t eat the gypsum core of the panel. Instead, they feed on the thin cardboard paper that covers both sides of the sheet, often without disturbing the paint on the surface. This makes termite damage in drywall surprisingly hard to spot until it’s well advanced.
What Termites Actually Eat in Drywall
Drywall (also called sheetrock) is a sandwich: a gypsum plaster core wrapped in paper. That paper is cellulose, the same material found in wood, and cellulose is what termites are after. They’ll consume the cardboard covering while leaving the brittle gypsum and even the surface paint largely intact. The result is a wall that looks fine from a few feet away but has been hollowed out from behind.
This is why termite damage in drywall often goes unnoticed for months or longer. The painted surface acts as a shell over feeding activity happening just beneath it. By the time visible signs appear on the wall’s surface, termites have typically been active inside the wall cavity for some time, also targeting the wooden studs, plates, and other framing behind the drywall.
How to Spot Termite Damage in Drywall
The signs are subtle, and you need to know what to look for. Here are the most reliable indicators:
- Pinholes with mud spots. Tiny, BB-sized dots of dried mud on a wall or ceiling are one of the clearest signs. These appear when termites accidentally chew through to the surface and then seal the hole with mud to block airflow. Pest control professionals call these “pinholes,” and even one or two on an interior wall warrant investigation.
- Sunken or winding lines beneath paint. Narrow, depressed trails visible under the paint surface suggest termites have eaten the paper layer underneath. These may look like faint, wandering grooves or slightly sunken tracks running across the wall.
- Mud tubes on walls or foundations. Pencil-width tubes made of soil and saliva running up foundation walls, along interior walls, or across ceilings are a hallmark of subterranean termites. These tubes protect the colony as it travels between its underground nest and your walls.
- Bubbling or blistering paint. Paint that looks warped or lightly blistered, especially near the base of a wall, can indicate termite feeding beneath the surface.
- A hollow sound when tapped. If you knock on a section of drywall and it sounds noticeably more hollow than surrounding areas, the paper backing or the wood framing behind it may have been consumed.
Subterranean vs. Drywood Termites
Both major termite types can damage drywall, but they leave different calling cards. Subterranean termites are the more common culprits across most of the United States. They live in underground colonies and build mud tubes to reach above-ground food sources. If you see mud tubes along your foundation or inside wall cavities, you’re dealing with subterranean termites. Their damage tends to follow a path from the ground up, starting at the lowest points of the wall.
Drywood termites don’t need soil contact at all. They nest directly inside the wood or wall material they’re consuming, which means they can show up anywhere in the home, including upper floors and attic spaces. Instead of mud tubes, drywood termites leave behind frass: tiny pellets that look like coarse sand or coffee grounds, often found in small piles below scattered kick-out holes in the wall. You might also notice small, clean holes in the drywall surface where they’ve pushed waste out of their galleries.
Termite Damage vs. Water Damage
Bubbling paint and warped-looking drywall can be caused by either termites or moisture, and the two get confused regularly. A few differences help you tell them apart.
Water damage typically leaves discoloration: brownish or yellowish stains, often with ring-like patterns that spread outward. The drywall underneath feels soggy or spongy, and you may notice a musty smell from mold growing in the damp material. Peeling wallpaper paired with that musty odor strongly points to water.
Termite damage rarely produces stains or odor. Instead, look for those telltale mud spots, the faint grooves or sunken trails beneath paint, or any sign of frass or discarded wings near the wall. Wood damaged by termites tends to look blistered or wavy rather than wet. If you press on it, it may crumble or feel papery thin rather than soft and damp. Finding mud tubes anywhere nearby settles the question.
How Treatment Works
Treating termites in drywall depends on the species and the extent of the infestation. For subterranean termites, the priority is breaking the connection between the colony underground and the structure above. This typically involves treating the soil around and beneath the foundation with a liquid barrier, or installing bait stations that the workers carry back to the colony. The mud tubes are a roadmap to where they’re entering.
For drywood termites with a localized infestation, a common approach is the drill-and-fill method. Small holes (1/8 to 1/4 inch) are drilled into the drywall, usually about 18 inches up from the floor and between each wall stud in the infested area. A foam or gel product is then injected through those holes into the wall cavity. The products used are non-repellent, meaning termites can’t detect them. They pick up the treatment on their bodies and spread it to other colony members through normal contact. This transfer effect is what eventually eliminates the colony, but it takes time. Expect up to 90 days for a non-repellent treatment to fully work through the population.
Widespread drywood infestations, especially in multiple walls or floors, may require whole-structure fumigation, where the entire home is tented and treated with gas. This is more disruptive and expensive but reaches termites in every hidden void at once.
Assessing and Repairing the Damage
Drywall itself is relatively cheap to replace. The bigger concern is what’s behind it. Once you remove damaged drywall panels, you can see the condition of the wooden framing: studs, top and bottom plates, headers above doors and windows. If termites have been feeding long enough, structural wood may be significantly weakened.
Minor surface damage to drywall paper, where the gypsum core and framing are still solid, can be patched and repainted. But if the paper has been consumed over large areas, the drywall becomes fragile and crumbly and needs to be cut out and replaced. Any compromised framing lumber should be sistered (reinforced with new wood alongside it) or fully replaced before new drywall goes up.
The key step people skip is confirming the infestation is fully eliminated before closing the wall back up. Repairing drywall over an active colony just hides the problem again. A follow-up inspection after treatment, ideally by a licensed pest professional, confirms the termites are gone before you start repairs.
Why Early Detection Matters
A mature subterranean termite colony can contain hundreds of thousands of workers feeding around the clock. The damage accumulates slowly at first but accelerates as the colony grows. Most homeowners don’t notice anything until the cosmetic signs, like pinholes or sunken paint lines, finally break through to the visible surface. By that point, the framing behind the wall has often sustained more damage than the drywall itself.
Annual termite inspections catch activity before it reaches that stage. If you live in a region where termites are common (most of the southern and southeastern U.S., coastal areas, and anywhere with warm, humid conditions), a yearly check of your foundation, crawl space, and interior walls is one of the most cost-effective things you can do to protect your home. Catching a mud tube on a foundation wall early can save you from discovering hollowed-out studs later.