Subterranean termites damage homes without being detected because they almost never feed in the open. They live in the soil, reach a house through underground tunnels or mud tubes, and eat structural wood from the inside while the surface stays intact. The University of California’s integrated pest management guide to subterranean termites notes that most homeowners don’t know they have a problem until something significant turns up, such as damaged wood found during a remodel or a swarm of winged termites indoors. Knowing how termites stay hidden, and where they leave traces, is the most practical way to find them sooner.
Saela Pest Control, a residential and commercial pest control company based in Orem, Utah, inspects and treats homes for termites. Below, Saela explains how termites hide inside wood, why a colony can stay out of sight for years, which parts of a house they damage most often, and what an inspection looks for.
Termites Eat Wood from the Inside Out
The main reason termite damage goes unseen is the way subterranean termites feed. They are soft-bodied insects that dry out quickly, so they need moist, enclosed spaces and rarely come into open air. Inside a board, they generally follow the grain, eating the softer springwood and leaving the harder summerwood. The tunnels they leave behind are hollow, completely enclosed cavities, so the outside of a beam, baseboard or window frame can look normal.
Because the outer layer stays in place, damage often turns up by accident. UC IPM describes damaged wood as typically thin at the surface and easily punctured with a knife or screwdriver, and it may look darkened or blistered. You might first notice a baseboard that gives way when a vacuum bumps it, paint that bubbles, or a door frame that sounds hollow when tapped. Knowing the early signs of termite damage to look for helps you catch these clues before the wood beneath is badly weakened.
Why Colonies Stay Hidden for Years
A subterranean termite colony grows slowly at first, and Utah State University Extension’s subterranean termite fact sheet notes that an infestation can go unnoticed for one to eight years. A fully developed colony can have well over 1 million members, yet the workers rarely come into the open; they travel through the soil or inside mud tubes. Homeowners generally don’t notice the feeding itself. What they see instead are winged swarmers in spring, mud tubes crossing concrete or other surfaces that aren’t wood, or frass on or near wood.
Mud tubes are how termites cross foundations and other gaps without drying out. Workers build them from a mix of saliva, wood and soil over concrete, brick, plaster and even metal, and working tubes are about a quarter inch to an inch across and stay moist inside while in use. Because they are usually built along foundations, in crawl spaces, behind walls and under slab floors where few people look, a colony can feed for a long time before anyone spots a tube. Saela’s 50+ point property inspection covers structural gaps and basements, so the lower parts of a house get checked even if you rarely go there.
Structural Areas Termites Most Often Damage
Subterranean termites go where wood is close to the soil or stays damp. According to Utah State University Extension, any wood in direct contact with the soil is a point of infestation, and that areas with extra moisture are particularly attractive. If you’re shopping for a house, these are the spots to ask about; see what every homeowner should know before buying an older home. These are the places where hidden damage most often builds up:
- Sill Plates and Floor Joists: These sit closest to the foundation, so foraging termites often reach them first. They also carry the weight of the floors above, which is why activity here deserves prompt attention.
- Wall Studs Behind Drywall: Termites can travel up from the foundation into wall framing through mud tubes or tunnels in the wood. With drywall on both sides, the damage stays hidden until paint blisters or the wall is opened during a remodel.
- Subflooring: Plumbing leaks, condensation and poor ventilation keep subfloors damp, which makes them more attractive to termites. Soft or sagging spots in a floor can mean the wood underneath has been damaged.
- Crawl Spaces and Basements: These dark, humid areas are rarely visited, so termites can work there undisturbed. UC IPM recommends that, ideally, wood beneath a building sit at least 12 inches above the soil, with foundation areas kept well ventilated and dry.
Why Regular Inspections Matter
Because subterranean termites stay out of sight, waiting for visible damage usually means a colony has already been feeding for some time. Utah State University Extension calls regular inspection the first step to minimizing feeding damage, and a schedule only helps if the visits actually happen. In a February 2024 Google review, Terry Sotta wrote that the technician “checks to determine if we have any issues & addresses them.” Between inspections, you can make your home less attractive to termites by removing wood-to-soil contact, fixing plumbing and roof leaks, keeping gutters clean, and keeping crawl spaces dry and ventilated.
A trained inspector knows where termites tend to hide and what traces to look for: mud tubes along foundations, piers, sill plates and joists; swarming termites or their shed wings near windows; frass; and wood that is blistered, thin at the surface or hollowed out along the grain. UC IPM points out that these signs often sit in dark and sometimes hazardous places, such as attics and tight crawl spaces, which is one reason it recommends a licensed professional for the inspection. Saela’s technicians are trained by Dennis Weiss, Saela’s entomologist, who also develops its pest-control protocols, audits service quality and holds the Entomological Society of America’s Board Certified Entomologist credential in urban and industrial entomology.
How Saela Treats Hidden Termite Activity
If an inspection turns up termite activity, Saela’s termite control packages use Trelona bait stations, and the upgraded package adds a Termidor perimeter treatment. Inspection schedules and re-treatment coverage depend on the plan you choose, and Saela prices each property individually based on pest type, location, property size, visit frequency and treatment products.
If you’ve found mud tubes, blistered paint or wood that sounds hollow, book a call to schedule a termite inspection. On Google, Saela’s Lakewood, Washington location is rated 4.8 out of 5 from 1,164 reviews as of October 2026.
Who wrote this article?
Devin Hutchings (Marketing Director at Saela Pest Control) wrote this article.
Devin leads Saela’s marketing and growth strategy. He brings more than 15 years of marketing experience across Uber, C.R. England, Lugg, and Neighbor. His background spans customer acquisition, retention, and developing marketing channels for service businesses and consumer marketplaces.
