5 animals that may be burrowing in your wall
Nighttime scratching, rustling, or gnawing in the wall rarely goes unnoticed for long. But before you set out a trap, poison, or a repellent, it is worth finding out what has moved in. After all, the next step is not the same if it is a mouse, rat, dormouse, stone marten, or bat.
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Mouse
The prime suspect. A mouse can easily get behind drywall, into the ceiling structure, or into the cavities behind kitchen cabinets: even a gap about the width of a pencil may be enough for it.
Tiny, dark droppings, gnawed food packaging, and openings around pipes or cables most often signal its presence. If the noise is coming from inside the wall, also look for the point where it comes out into the room, attic, or basement in search of food.
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Rat
A rat’s movement and gnawing are usually more forceful, and the droppings it leaves behind are much larger than a mouse’s. It often gets in from the basement, the foundation, drains, or around utility lines, but it can also reach other parts of the building along walls and service shafts.
If you find fresh signs in several places, see the animal during the day, or the problem returns after a short time, it is worth calling a pest control professional. A full rat infestation is rarely solved by a single device placed once.
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Dormouse
A dormouse may mainly appear in houses close to forests, gardens, or orchards. It likes to use attics, roof structures, and other sheltered cavities, and can make surprisingly loud noises for its size. Fruit or seed remains, as well as more forceful nighttime movement than a mouse’s, may point to it.
It is important to know that local dormouse species are protected. If you suspect a dormouse is present, do not poison it, do not trap it yourself, and do not seal it inside the cavity. Ask for help from the relevant national park authority or a wildlife conservation specialist.
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Marten
The stone marten usually does not live in a narrow wall cavity, but rather moves around in the attic, ceiling structure, or larger spaces behind cladding. Because of this, the sound can easily seem as if it is coming directly from inside the wall.
Heavier thumping, pulled-apart insulation, an animal that regularly defecates in the same place, and an unpleasant smell may indicate its presence. If the noise mainly comes from the roof, first check the eaves, roof junctions, and attic entry points.
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Bat
Several bat species use roosts formed in gaps in buildings, under cladding, or in roof structures. Their presence may be indicated by tiny droppings collecting below the entrance, the emergence of bats at dusk, and the faint scratching or chirping heard from the gap.
In Europe, all bats are protected, and their roosts cannot be sealed off at random. If you find a bat, do not use poison or a rodent trap against it; instead, contact the relevant national park authority or wildlife conservation office.
What should you do if you’ve found the culprit?
If it is a mouse or rat, find the route it is using, cut off access to food and water, deal with the animals already inside, and only seal the gaps after the activity has stopped.
If the rodent is moving behind drywall, read this: how do you handle a rodent that has moved behind drywall?
If it is rather the attic or an open loft that is affected, you can find a detailed guide here: what should you do if something is scratching in the attic?
An ultrasonic repellent is only worth placing in an open space where there is no wall, ceiling structure, or insulation between the device and the animal. If the identified rodent route can be covered this way, you can find the Vadalarm ultrasonic rodent repellent here.
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