How to Get Rid of Mice in the Walls

For such small creatures, mice can do a huge amount of damage to your home and belongings. The chances are if you have mice anywhere else in your home, you also have mice in the walls and mice in the crawl space and attic. There are many things you can do to get rid of mice in walls, but keep in mind that you still may need to hire an exterminator if the mice persist.

Mice in the walls are very dangerous, causing extensive damage, health hazards, and a possible fire. Get rid of mice in the walls right away. Use traps outside the walls. Use poison with care. Seal up any entranceways. If all else fails, hire an exterminator.

Are mice in the walls dangerous?

Mice in your walls or ceiling are extremely dangerous. They mainly pose problems in three ways:

  • Damage – those incredibly little teeth can chew up just about anything, from drywall to dollar bills. They also ruin possessions and food through their droppings and urine.
  • Health hazards – mice spread many diseases and often carry parasites that can spread throughout your home to your pets or you.
  • Fire – mice chew on anything. This is how they find out whether something is good to eat or not. When they chew on live electric wires, they can set themselves on fire and cause the rest of your home to burn, too.

mice in walls

What do mice in the walls sound like?

You know the old saying, “Quiet as a mouse”? This is true for one mouse, even a mouse in walls. Unfortunately, when you have one mouse, many others will follow. Mice breed quickly and tend to be friendly towards each other.

Hearing squeaking or “EEEK” coming from the walls or ceiling is a dead giveaway that you have mice. Usually, that only happens when you have so many mice that they keep bumping into each other or baby mice are playing. They usually squeak when they play.

Before hearing the dreaded squeaking, you'll often hear other noises. You will hear them most often at night (usually when you're just about to fall asleep) because mice prefer the dark. These include:

  • Scampering a quick series of beats coming in sporadic bursts, reminiscent of the crinkling newspaper.
  • Nibbling or chewing.
  • Thumping or thudding, which may sound very un-mouselike and may make you wonder if you have raccoons and not a mouse in the walls.
  • Noises in spaces like walls, crawl spaces, air ducts, and attics tend to amplify.
mouse droppings
Elongated mouse droppings.

Are mice in the walls but not in the house?

It may seem like you have mice in walls but not in a house or apartment. That's only because you have not looked hard enough. You may not hear or see mice in the rest of your home, but they are there.

Look for:

  • Droppings – about a quarter of an inch long, black and thin.
  • Damage – check anything on the floor, on countertops, or near the walls. If they have holes of any size, you have mice. They go for people's food, pet food, clothes, newspapers, cardboard boxes, plastic, soap, and even steal tampons to make nest material.
  • Nests – roundish clumps of tightly packed soft materials like grasses, shredded newspaper, tampons orbits of your clothes. They can be found in drawers, closets, crawl spaces – anywhere dark and secluded.

snap straps for mice in walls

Getting rid of mice in walls: Set traps

Mice do not spend their whole time inside walls or air ducts. They come out when they think no one is looking to case the joint for food, water, and nesting material. This means they come out anywhere a lot of food is stored such as kitchens, basements, garages, pantries, and closets.

Just assume that anywhere food is stored, mice are prowling. Set mouse snap traps along the walls and behind dark places like the refrigerator. Bait them with peanut butter, which mice find irresistible. Check them every day and every time you hear a SNAP.

Also place traps wherever you find droppings, nests, or other signs of damage. If possible, place traps in crawl spaces or the attic.

Warnings about using poison bait to get rid of mice in walls

Poisoned bait stations are an effective way to kill mice. They are placed in the same areas where you place snap traps. You need to be VERY careful with this poison. Unless you are absolutely 100 percent sure your pets and your kids cannot get into the bait to eat it, DO NOT use poison unless it is secured in a bait box.

Related: How do you get rid of rats and mice without using poison?

Another problem with using poison is that you may see more mice than ever before. They tend to crawl into the middle of the floor or in other conspicuous areas to die. They will be bloated (so they look really fat or pregnant) and will be bleeding from the face. You need to check your home daily for these dead mice.

It is possible for a dog or cat that eats a poisoned mouse to also get poisoned. This is a medical emergency. Contact your vet immediately for an antidote, usually shots of Vitamin K. Signs of poisoning in pets include:

  • Vomiting
  • Diarrhea
  • Seizures or uncontrollable twitching
  • Loss of coordination.

Another way of getting rid of mice in your walls

Are you good with tools? If you want to be sure to trap mice where you know they are the walls follow these steps:

  • Drill a hole the size of a nickel into the bottom of a wall.
  • Cut the same-sized hole in a cardboard box.
  • Tape cellophane over the hole in the box to give you a peep-hole.
  • Place a peanut butter baited snap trap in the box.
  • Place the box in the hole in the wall.
  • Check every day for dead mice and remove corpses promptly. Dead mice start to smell after a while.

Tips for cleaning up your home

Mice love messy homes. They can live on crumbs in the carpet, stealing pet food right out of the pet's dish and snacking from your garbage. By cleaning up, you not only make it hard for your mice to find any food but also make the baited traps or poison bait look more desirable.

Be sure to:

  • Place all trash and garbage in sealed, chew-proof cans.
  • Clean up the mess under bird feeders once a day.
  • Pick up all pet food or pet food dishes off of the floor or porch.
  • Get rid of piles of newspaper, mounds of dirty laundry, or other clutter.
  • Keep the yard tidy by mowing regularly, trimming hedges or shrubs, and getting rid of the trash or junk in the yard. This reduces places where mice can hide, live and tunnel their way into your home.
  • If that seems like too much work, consider this snakes often eat mice. They follow mice wherever they go. So, if you do not want snakes surprising you in your home, make sure to clean up so that mice don't get in your home.
wood mouse
Image credit: Hans, Pixabay

Related: How to get rid of rats in your house fast

How to prevent mice from returning

Getting rid of the mice currently living in your home successfully is no guarantee that more mice won't find your home and move in. You must take steps to make your home as unattractive to mice as possible to prevent them from getting back in. How do mice get in walls? By finding any weakness they can exploit.

  • Fix all leaks – whether a leaky pipe, a loose window, or a damp attic, do not delay getting these fixed. These leaks give free water to mice. They also cause rotting and decay of walls and flooring, which makes it much easier for a home-hunting mouse to chew and tunnel through.
  • Block the bottom of doorways to any door leading outside. Mice only need a tiny crack in order to slip underneath.
  • Check your dryer ventsmouse-proof your dryer vent using a vent cover or mesh.
  • Go around your house carefully and check the foundations, especially ground floor windows and any pipes or cables leaving the home. Use caulk, steel wool, wire mesh-like to plug up any holes.
  • Only plug up all of the holes AFTER you are sure the mice are gone, or you may risk mice dying in the walls.

Advice for people in townhouses, condos, or other connected housing

If your home shares one or more walls with another home, then expect mice to come back. You can do all you can to get rid of mice and prevent them from coming back but you cannot guarantee that your neighbors will be so diligent. Mice can and will get to your home through the connecting wall or walls with your neighbors.

The good news is that you are not helpless. At the first sign of another mouse, do all you did before to get rid of them. This will work again until the next time. Keeping your home and yard free of trash and clutter, fixing leaks, and placing your belongings in mouse-proof containers will go a long way to make your home less attractive to mice.

In conclusion

Mice in crawl space, mice in walls, or mice in the air ducts need to be eliminated right away. They can cause incredible damage to your home, possessions, and health. Use snap traps, clean up and plug all holes into your home where you can so mice can't get back in.

If you are handy with tools, drill a hole in the wall and place a trap there. Make sure the yard is tidy and a messy yard full of food and hiding spaces attracts mice and snakes. If you still see mice or signs of mice after all of this, please hire an exterminator.