If you have mice in your walls, this can be a problem for several reasons. Mice can cause damage to your home by gnawing on wires and chewing through drywall. They can also spread diseases such as hantavirus and salmonella. Mouse droppings can contaminate food and surfaces, and if that isn't enough, mice in the walls are a serious nuisance with all their scurrying and noise.
If you suspect you have mice in your walls, it's important to take action to prevent them from causing further damage or spreading illness. You can contact a pest control company to have the mice removed, or you can try some do-it-yourself methods. Either way, it's important to address the problem as soon as possible.
Not only can mice spread disease, but if they are chewing on wires inside your walls, this could create a fire risk. If you have mice (or something else) in your walls, it's important that you deal with it quickly, and don't be afraid to call in professional help if you feel in over your head.
What Do Mice Look Like?
Mice are small rodents that typically have grey or brown fur. They have pointy noses, long tails and large ears. Mice typically live in fields and forests, but they can also be found in homes and other buildings. Mice usually enter homes through small openings, such as gaps in the walls or cracks in the floor. Once inside, they may build nests out of insulation or other materials they find in the walls, crawlspace, attic or garage.
Mice are attracted to food sources both inside and outside. These food sources might include:
- Areas where the mice can access garbage
- Spaces where mice are getting into the pantry or cabinets
- Pet food left out for easy mouse access
Mice also chew on wires or other parts of the home, which can cause damage. Mice can be a serious nuisance, but don't worry! There are several ways to go about getting rid of them.
5 Ways to Get Rid of Mice in Walls
Mice in walls can be a real bother, and getting rid of them isn't easy. Luckily, there are a few things you can do to mouse-proof your home and get rid of mice in the walls.
Seal Mice Out of Your Walls
Mice are notoriously difficult to keep out of homes and other structures. They are able to squeeze through incredibly small spaces. An adult mouse can squeeze through a hole the size of a dime, and once mice gain access to a building, they can quickly build a nest and start breeding.
One of the most common ways mice get into homes is by crawling through gaps in the walls, under the siding, and around the foundation. To prevent mice from getting into your home, it's important to seal any cracks or holes around the exterior of your home. If mice are getting into your walls, conduct an inspection of the vents around your home, especially the crawlspace and attic vents. Use a flashlight to clearly illuminate any damage to the vents. Are the mice accessing your garage? Make sure your garage door sweeps are free of gaps and holes and that they seals tightly against the ground.
What is an Entry Point?
An entry point is anywhere the rodent is able to gain access to the inside of your home. These spaces may naturally occur on their own, or mice may find small gaps and chew them out to make them larger for easier access.
While spray foam is a popular choice for sealing homes against mice, it is not a good option for rodent control of any kind. Spray foam will not keep the mice out of your walls, as rodents can chew right through spray foam like popcorn. Instead, opt for filling holes tightly with steel wool or fastening wire mesh patches over entry points using screws. Just make sure the holes in your mesh are small enough that mice can't fit through—1/4" hardware cloth should do the trick.
Don't Attract Mice to Your Home
Mice are attracted to a wide array of food sources. The are considered opportunistic feeders, which mean they will eat just about anything they can find.
Outdoors, mice eat:
- Fruits and vegetables
- Carcasses of dead animals and birds (yuck!!)
If mice find their way into your home, they will likely eat any food that's out, such as:
- Pet food
Even crumbs are enough to attract mice, so make sure your indoor and outdoor spaces stay free of food debris if you're wanting to avoid attracting mice.
Also keep in mind possible water sources that could draw mice into your home. After all, if you're attracting mice from the landscape, they could end up accessing your inside spaces through the walls, crawlspace and other areas. Possible water sources include:
- Yard water fixtures such as ponds
- A leaky garden hose (or even an irrigation hose)
- Damaged or leaking pipes
- Animal water dishes
Reduce Yard Debris and Surrounding Vegetation
To avoid a mouse infestation, it is important to remove potential nesting sites from around the home. Outdoors, mice will often build nests in locations like:
- Hollowed stumps
- Dense bushes
- Among rocks
- Piles of leaves
- Wood piles
In regards to the woodpile, you may not be able to get rid of it, but consider moving it away from home. If it's right up against the foundation, mice could access inside the walls, especially if there are any gaps under the siding.
Mice can also access homes using the surrounding vegetation. Mice can commonly be found in landscaping where they like to hide in dense vegetation and can use overgrown plants to climb up for access to your home.
Before proceeding with this step, it is absolutely essential that you know you're dealing with mice and not rats. If you choose to use snap traps and you place mouse snaps when it is actually rats that you're dealing with, the traps will not be big enough to deliver a lethal blow to the rats, but it will scare them plenty and teach them that traps are dangerous. They will then become wary of all traps and eliminating them will be harder.
If you are dealing with a severe mouse issue. consider using glue traps. These are considered not as humane as other traps, but other traps must be emptied and reset each time they catch something. Glue traps can be very helpful when placed once to catch multiple mice before they need to be switched out.
If you're not sure if they're rats or mice, consider calling a local pest control company for a second opinion.
Call the Pros
If your mouse situation is especially puzzling, or if you believe poison or other chemical controls might be necessary, it's best to call a pest control company. When baits are improperly placed, it comes with threats to the local animal populations. Baits should be kept in locking, anchored stations in order to keep children, pets and other animals from accessing them.
When shopping for pest control, look for a local company that specializes in Integrated Pest Management (IPM).
Signs of a Mouse Infestation in Your Walls
When it comes to mice in the walls of your home, the most telltale sign of their presence will be the sounds of running or scurrying inside your walls. If you are also finding tiny little droppings the size of a grain of rice or smaller, this very well could be mice.
Mice and rats are nocturnal. If you're hearing scurrying sounds around dark, it very well could be rodents. If the sounds you're hearing are during the day time, you could be hearing a bird, squirrels, or even a yellow jacket nest depending on the time of year.
Understand that if you're hearing sounds in your walls, this warrants further investigation. Don't jump straight into mouse control measures. Inspect further and get a positive identification on the pest in question before carrying out any attempts to control them.
What Causes Mice in Walls?
There are a number of factors that can contribute to a problem with mice in the walls.
First, make sure you're actually dealing with mice and not something else. Then, ask yourself the following questions:
- Where could the mice be accessing the walls of your house?
- Are they able to find food and water nearby?
- Could the mice be using the surrounding vegetation to access your home?
How to Prevent Mice in Walls
If you want to prevent mice from getting into your walls, there are a lot of things you can do to make sure they don't get in, especially:
- Cleaning up any potential food sources
- Removing harborage areas where mice could be seeking shelter such as ivy or other dense vegetation
- Making sure gaps around your home are properly sealed (not with spray foam)
- Using the right traps and equipment to control mice
Overall, if you're interested in keeping mice out of your walls, start by keeping a tidy yard and home. Eliminate food sources (including bird feeders) and ensure that your foundation is free and clear of debris and overgrown plants.
Rodent Management, Connecticut Department of Energy and Environmental Protection
Rodents, Washington State Department of Health
Controlling House Mice. University of Missouri Extension.