The most common insects making noise inside your house at night are crickets, but they’re far from the only possibility. Depending on the sound you’re hearing, the source could be anything from a single cricket trapped in a corner to a colony of carpenter ants tunneling through your walls. The type of noise, its volume, and where it’s coming from are the best clues to figuring out what you’re dealing with.
Crickets: The Most Likely Culprit
If you’re hearing a repetitive, rhythmic chirping, a cricket has almost certainly found its way inside. House crickets and field crickets are both attracted to warmth, light, and moisture, which makes basements, garages, kitchens, and bathrooms prime real estate. Males chirp by rubbing their front wings together to attract females, and they do it almost exclusively at night. A single cricket can produce a surprisingly loud sound that carries through an otherwise quiet house.
Cricket chirping actually speeds up or slows down with temperature. This relationship is consistent enough that NOAA references a formula from 1897 called Dolbear’s law: count the number of chirps in 15 seconds, add 40, and you get a rough estimate of the temperature in Fahrenheit. So if the chirping sounds frantic, your house is probably warm. If it’s slow and lazy, the room is cooler.
A lone cricket is harmless and will usually die within a few weeks indoors. If you’re hearing multiple crickets, though, they may be breeding in a damp area like a crawl space or basement.
Carpenter Ants: Rustling Inside Walls
If the sound is less of a chirp and more of a soft, continuous rustling, like crinkling cellophane, you may be hearing carpenter ants. A large colony chewing through wood and moving inside wall cavities produces a faint but audible noise, especially at night when background sounds drop away. You might also hear tiny clicking or tapping sounds. Carpenter ant soldiers communicate by tapping their bodies against tunnel walls, and workers rub body parts together in a behavior called stridulation that creates faint squeaks.
These sounds tend to come from a specific spot in a wall, floor, or ceiling. Press your ear against the surface or hold a glass to the wall to amplify it. Unlike crickets, carpenter ants signal an active structural problem. They don’t eat wood, but they excavate it to build nests, and over time they can cause real damage. If you’re hearing rustling inside your walls paired with small piles of sawdust-like shavings (called frass) near baseboards, carpenter ants are the likely source.
Termites: Slow, Rhythmic Chewing
Termite noise is subtler than carpenter ants and harder to detect. Drywood termites produce a slow, rhythmic chewing sound as they eat through wood from the inside out. You’re most likely to hear it in a quiet room at night, pressed close to a wall or wooden beam. Tapping on wood that sounds hollow is another sign, since termites consume the interior while leaving the surface intact.
Soldier termites also headbang against tunnel walls to warn the colony of threats, producing faint clicking. But in general, termite sounds are so quiet that by the time you can hear them without pressing your ear to the wall, the infestation is likely large.
Deathwatch Beetles: Ticking in Old Timber
A mysterious tapping or ticking sound coming from wooden beams, rafters, or old furniture could be a deathwatch beetle. These wood-boring insects communicate by literally banging their heads against the wood surface in rapid bursts of six to eight taps. Males tap first, and females respond within about two seconds. The male then taps again anywhere from 2 to 30 seconds later, creating an eerie, irregular ticking pattern.
Deathwatch beetles are most common in older homes with structural timber, and you’re most likely to hear them on quiet summer nights. The larvae bore through wood over several years before emerging as adults, so the tapping you hear means the beetles are mature and mating. That also means larvae have been feeding on your wood for a while. Look for tiny round exit holes in beams or furniture as confirmation.
Katydids and Other Accidental Invaders
Sometimes the noise maker isn’t a permanent resident. Katydids, close relatives of crickets and grasshoppers, are primarily nocturnal and occasionally wander inside through open doors or windows, especially in late summer. Their calls range from the classic “Katy-did, Katy-didn’t” rasping of the common true katydid to continuous trills, clicks, and buzzes, all produced by scraping specialized structures on their front wings together. Indoors, a katydid’s call is startlingly loud for the size of the insect. Their long antennae, often longer than their body, help them navigate in darkness.
Wasps can also create unexpected nighttime sounds. A dormant wasp nest in a wall void can sometimes reactivate when warmed by indoor heat, producing a low, dull humming or buzzing from a specific spot on the wall. This one is worth addressing quickly, since disturbed wasps in an enclosed space present a sting risk.
How to Identify the Sound
Narrowing down the insect starts with characterizing what you hear:
- Rhythmic chirping that speeds up in warmth: cricket, likely in an open room or behind an appliance.
- Soft, continuous rustling or faint scratching from inside a wall: carpenter ants moving through tunnels or chewing wood.
- Slow, faint chewing audible only when you press your ear to wood: termites.
- Ticking or tapping in bursts of six to eight from wooden beams or furniture: deathwatch beetle.
- Loud rasping, buzzing, or trilling from a single location in a room: a katydid or other outdoor insect that got inside.
- Low, steady humming from one spot on a wall: a wasp nest in the wall cavity.
Time of year matters too. Crickets and katydids are most active in late summer through fall. Deathwatch beetles tap in summer. Carpenter ants and termites are year-round problems, though their sounds may be more noticeable in winter when houses are quieter.
How to Stop the Noise
For a single cricket or katydid, the fix is simple: find it and relocate it outside, or wait it out. Crickets are attracted to light, so turning off unnecessary lights near entry points reduces the chance more will follow. Sticky traps placed along baseboards in basements and garages catch crickets effectively.
For carpenter ants, termites, or deathwatch beetles, the sounds indicate a problem that goes beyond nuisance. These insects cause structural damage over time, and the noise means a colony or infestation is already established. A professional inspection is the fastest way to assess the scope. Inspectors typically check foundation walls, sill plates, and areas around plumbing for signs of activity, using moisture meters to find the damp conditions these pests prefer.
Preventing noise-making insects from settling in starts with moisture control. Keep indoor humidity below 50 to 55 percent using a dehumidifier, especially in basements. Fix plumbing leaks immediately and insulate cold-water pipes to prevent condensation. Outside, make sure gutters and downspouts discharge water 5 to 10 feet from your foundation. Seal cracks in foundation walls and around pipe penetrations, and store basement items in sealed plastic bins rather than cardboard boxes, which absorb moisture and attract insects looking for shelter.