How to get rid of mice in the garage this winter

Have an attached garage? It may be how the mice are getting into your house. 

Make sure that garage door seals correctly. If it doesn’t you might need the Xcluder Rodent-Proof Garage Door Seal.

Tim Horgan, Service Manager at Debug Pest Control

An attached garage is an often overlooked portal for mice looking to get into your house for the winter. Every time you open the garage door to leave for work, come home from work, or do any kind of car maintenance or chore in your garage–you’re creating an opportunity for mice to enter your home. 

And once mice are in your garage, it’s only a matter of time before they get into your much warmer house. 

How do I know if I have mice in my garage?

If there are mice in your house, they are probably the common house mouse variety. They’re very small and come in a wide range of colors from white, gray, brown, and black. They have a pointed snout, small eyes, and round ears. 

If the mouse you are seeing has a white underbelly, bigger eyes, and a short tail, you may have a deer mouse in your house. If you aren’t sure, a professional pest control technician can easily identify the mouse you have in your garage. 

Maybe you haven’t seen a mouse and instead you’ve seen their droppings and grease trails in your garage. Maybe you’ve seen their bite marks on your bags of bird seed. If you are seeing signs like this, chances are the mice have moved in, you just haven’t seen them yet.

How are they getting in?

As we mentioned earlier, your garage door is a major point of entry. But, they can get in even if you don’t open your garage door all winter. Your garage is safer and warmer than outside and mice are going to do everything they can to gain entry to your garage. 

Mice only need ¼ inch opening to enter your garage; that’s really, really small. 

Are there easy ways to keep mice out of my garage?

One of the easiest things you can do is to declutter your garage as much as possible. Don’t give mice anywhere they can easily hide and avoid detection. The more stuff you have in your garage, the harder it is to detect the mice. You want to spot the mice early–when there are only one or a few mice in the garage. The more clutter you have, the higher the chances of your not seeing the mice until you’re infested. 

Do yourself a favor. Skip the spray foam. Mice will chew right through that.

Tim Horgan, Service Manager at Debug Pest Control

Another easy, affordable preventative tip is to put your bird seed and pet food in sealed plastic containers. Bird seed and pet food are an easy food source for mice. They can easily chew through the plastic and paper bags that your bird seed and pet food come in, so it’s important to take the food out of those bags and pour them into sealed plastic containers. 

Some folks think they can go to the big box home repair stores and buy the spray foam. The spray foam is great for drafts, but does nothing to stop mice, who easily chew through the foam. Not only do those general spray foams not work, they often cause added damage to your home by trapping moisture and causing wood to rot. 

Caulk and steel wool are some easy and affordable DIY rodent control tools to help keep your garage free of mice. Go around the perimeter of your garage and apply fresh caulk along the foundation, around your windows, and in any cracks in your soffit or siding. Steel wool pushed into these openings makes it hard for rodents and mice to chew through any opening. 

Getting rid of mice that are already living in your garage

If there are mice already living in your garage–or if you’ve tried to get rid of them yourself, but they’ve persisted–it’s time to call in the professionals. Professional pest control can help you trap the mice living in your garage and also install professional exclusion devices like garage door sweeps.  

At Debug, we believe in the old saying that an ounce of prevention is worth a pound of cure. If you want to eliminate mice from your home, call us and we’ll come out and identify how the mice are entering your garage. We’ll work with you to identify their access points and then close those spaces up. We’ll install professional exclusion tools and we’ll monitor the situation to make sure it’s working. 

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Bonus Blog Article

7 Rodent-Proofing Tips & Tricks for Your Home

Many of us have been faced with some type of infestation problem in the home, either with insects or rodents. A survey that was taken in the United States for the National Pest Management Association in 2013 showed that 1/3 of the population faced problems with mice and rats. Now, some people may like these furry, whiskered little guys. Not when they appear in droves and start chewing their way through boxes of food though! Let’s look at where, when, and why these infestations begin before we take a look at how to prevent them.

Rodents are attracted to a cozy nesting area near an ample supply of food. Most rodent infestations occur in the kitchen or a pantry where food is bountiful. They can also occur in dark, cluttered areas like a garage, basement, or attic. The autumn and winter months tend to be the time of year when many infestations happen as well. Rodents come looking for a warm place to sleep and a space to hoard their food, which is usually being pilfered from your own cupboard in many cases.

Infestations can spread quickly due to the rapid rate of reproduction in rodents. One female mouse has the ability to give birth to up to 12 babies every 3 weeks. A female mouse can be ready to reproduce as early as at 4 weeks of age. Their gestation cycle is between 19-21 days. So you can see how the rodent population can grow so quickly.  This why rodent control in Rhode Island is important.

Rodents can also squeeze through very small spaces. Rats can get through a crack that is no bigger than a quarter and mice can scurry through a dime-sized crack. This is how they come to live and nest inside walls and under floors.

Rodents also carry ticks, lice, and fleas (look at what happened in medieval times when the black plague spread through Europe!) Rodents also urinate quite a lot and can drop up to 25,000 pellets of fecal matter in one year. Sometimes this becomes airborne and can be a cause for allergies and asthma.

Another danger of having a rodent infestation is that they tend to chew through wood and electrical wires, greatly raising the risk of starting an electrical fire in the home.

How To Rodent Proof Your Home


Make sure you seal any cracks or holes found outside of the home. This is especially important for areas where you have wires or cables running into the home from the outside. Any gap that is dime-sized or more is a potential doorway for a rodent to enter.
*Tip – A good hole filler that rodents can’t chew their way through is using steel wool or copper mesh and mixing it with caulking.


This is where mice can most easily get into your home. Your basement foundation and windows need to be checked for loose, crumbling mortar and old weather stripping. Replace weather stripping regularly. Make sure any small windows or vents in the basement are also secure with no gaps.

Plumbing and Moisture

Make sure any sites where moisture can gather is cleaned up. This would be areas where you may have leaking pipes or drains that are clogged.


Where and how you store food and seed is important in reducing the risk of a rodent infestation. If you store things like pet food, grass seed and birdseed outside of the house (in a shed for example), its best to have that storage at least 20 feet from the home and about 5 feet from the ground. Store food and seed in air tight, rodent-proof containers as well. Rodents are attracted by the smell of these things so it’s best to take precautions before they arrive rather than after the fact. Once a rodent has smelled food it will stick around looking for another source.

Some people use their garage for storing food items and the same rules apply here. Be sure to not leave your garage open for any extended periods of time like overnight.


We all have that one area or two where we allow clutter to take over. Usually this is in a basement, attic, or spare room. This also makes the perfect breeding ground for rodents. Keeping these areas as clutter-free as possible will go a long way in preventing a rodent outbreak.


Many people love to have gorgeous bushes and dense plants around the yard. However, these also make a safe haven for rodents to take up residence right outside the home. While you don’t have to give up on creating the landscape you desire, try to use some moderation and keep the denser foliage away from the structure of the house. Trim tree branches back so you have at least a 6-foot gap between house and tree.

*Tip – There are some plants that help repel rodents such as mint. You can plant these in strategic places outside of the home or used crushed leaves or mint oil in areas like cupboards and pantries. Another trick is to sprinkle used cat litter around the foundations outside of the home. The scent of a rodent’s natural predator can be enough to give them a second thought about visiting your home.

Sanitation: Indoors and Outdoors

Indoor Sanitation

Keeping the home clean inside and out can prevent rodents from taking an interest in your home to begin with. Inside the home make sure you clean areas where food may collect or fall, like under the stove, dishwasher, and refrigerator. Make sure you keep countertops clean and clear of food and store any dry food, seeds, and pet food in airtight containers. If you do have pets, don’t leave food bowls down at night. Make sure you don’t leave cups or bowls of water out overnight as well. All of these things can attract rodents.

Keep places like storage areas clutter-free and make sure supplies are being stored off of the floor. If you have those areas that are hard to access and often get neglected, make sure they are at least rodent proof.

Outdoor Sanitation

We have touched on this a bit already regarding landscaping and outside storage areas. If you store firewood it is best to keep it away from the house. It’s best to keep lumber and firewood about 18 inches off the ground. If you have debris like rock piles and old equipment laying around outside, make sure you have it removed. Make sure any outdoor garbage pails are shut tightly.

Many people like to feed the birds but this also can attract rodents. Using bird feeders is ok but you need to keep on top of them and keep them as clean as possible, as well as keeping them away from the house. It’s also important to clean up any spills of pet food, grass or birdseed right away.

When rodents come calling it is often not noticed until it is too late. This is why prevention is the best route to control rodent problems. If you do have a problem, make sure to call Debug Pest Control!

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