Rats in Attics and Walls

As rats require easy access to food and consistent warmth, especially during winter months, they often invade homes and other buildings. Most manmade structures feature easy access points, such as unsecured windows and doors, air conditioning units, and openings around utility pipes, that offer entry to rats and other pests.

Once inside, rats hide in secluded locations, like attics and inside walls, and reproduce at an alarming rate. As they cause damage with their constant gnawing and can even start electrical fires by chewing through wiring, residents should pay close attention for signs of rat infestations.

Norway rats are usually found in the lower portions of homes, while roof rats typically infest walls near ceilings or attics.

Rats in Walls

norway rat
norway rat in wall


These rodents are capable of squeezing through holes or cracks as small as half an inch in diameter, and they may leave easily detected signs of their presence outside these holes.


Sounds of gnawing, scuttling, clawing, small squeaking, or fighting, especially at night, are good indications of rat activity in walls.


The stench of dead rats, urine, and feces is also a warning sign. Such signs can include droppings or urine stains near baseboards, tracks along dusty or dirty corners of floors, freshly accumulated wood shavings or bits of insulation, and even smudge marks on walls from oily rat fur.

Since mice and rats behave similarly, it can be hard to tell which rodent is causing the infestation based on sounds and smells alone. Droppings larger than a grain of rice paired with smudging on walls left by oily fur coats generally point to the presence of rats over mice.

What Damage Can Rats Do in Walls?

If rats find their way inside a wall, they can cause considerable damage. Their teeth grow rapidly, which causes the rodents to continually chew on things to keep their teeth at reasonable lengths. When rats chew up insulation or use it as nesting material, it can become contaminated with urine and dropping leading to a potentially serious health hazard. Rats also have a tendency to chew through electrical wires, utility cables, and pipes. Damage such as power outages, water leaks, and even electrical fires can all stem from having rats in the walls. Humans and pets are also placed at higher risk of illness when rats are present, as they carry numerous transmissible diseases such as E. Coli and Salmonella.

Since rats an squeeze inside homes through the smallest of openings, making it essential to seal holes and cracks in foundations, roofs, doors, and windows. Setting out store-bought rat traps can be effective but is also costly and not always efficient.

Rats in the Attic

Hearing Rats in the Attic

Few things are more unnerving for homeowners than hearing strange noises coming from the attic. Hard to reach for humans, attics are easily infiltrated by rats. The filthy pests need only a gap as small as a half inch to squeeze inside, where they quickly find the warm, undisturbed area ideal for breeding. While many animals can get into this space, the worst possible scenario might be rats in the attic.

Roof Rats

Roof rats, also called black rats, are especially likely to be found in attics because they are excellent climbers and prefer to nest in high places off the ground.  One of the signs that there’s a roof rat in the attic is actually spotting the pest. Therefore, it’s important that residents are able to identify them.

Norway Rats

It is somewhat rare to find Norway rats in attics. Unlike roof rats, a similar species, they aren’t particularly agile creatures fit for climbing and jumping. However, if the lower level of a building already has too many rats nesting, or if something frightens them, Norway rats will move upstairs to live in the attic.

Problems with Rats in Attics

Homeowners with a rat in the attic start hearing scurrying and rubbing sounds around dusk, as the animals are more active at night. Residents may hear gnawing sounds as well, since the behavior is necessary to wear down a rat’s ever-growing teeth. Paired with the wood dust they leave behind when gnawing on joints and beams, the pests can cause fire hazards when they strip or short wires. Since they also carry numerous diseases, have parasites in their fur, and cause illness with their urine and droppings, rats in the attic can negatively impact resident health.

Control & Prevention

It’s a good idea to make sure the rodents cannot get inside in the first place. Any cracks and openings along the foundation and roofline should be sealed. Pay close attention to areas around exhaust pipes, vents, and cables as small openings are common in these areas.

How to get rid of rat infestations.