9 Simple Tips to Rat-Proof Your Garage


The purpose of a garage is to store a car, but according to a survey from Home Innovation Research Labs, a higher percentage of people use a garage for storage than for parking a car. According to the same survey, an average of 30% of garage space is used for storage. To protect the cars and items stored in a garage, we want to keep rats and other rodents out of the garage. 

To prevent rats from entering a garage, you need to identify possible entry points for a rat and then seal them so rats cannot use them. Although the most common entry point is the seal under the garage door, replacing the seal does not ensure the rats will stay out.

If you are looking for some tips to rat-proof your garage, you’ve come to the right place! Keep reading to find out why and how rats want to come into your garage or house and ways that you can keep them out.

How Do Rats Get Into a Garage?

The most obvious way for a rat to get into a garage is the garage door. If you can slide your finger in the gap under the door, then the rat can get in. I’ve seen our cats get in with just as much space. 4 legged critters are very nimble creatures!

So, just sealing that gap will not prevent a rat from entering if other accessible entrance places exist.

Rats can also enter a building through:

  • Vents. If you have a dryer in the garage, they can enter through the vent if it is not sealed correctly.
  • Digging. If your garage has a dirt floor, rats can dig under the foundation.
  • Openings. Rats can enter through openings around wires and pipes.
  • Climbing. Rodents have been known to use electrical cables to climb up to a roof. If they find a way to get into the eaves, they are in your attic. If they can make it that far, they can make it to your garage.
  • Drains. Most rats are excellent swimmers. If you have a drain in your garage, that could be another access point. Check that the drain guard is secure.

Some people seal the garage door and think they have rat proofed the garage. Although slinking in under the door is the easiest way for a rat to enter, it is not the only way in. To rat-proof a garage, all access points need to be sealed off!

Why Do Rats Want to Go Into a Garage?

When a rat wants to get into a garage, it does so for one or more reasons:

  • Food. Most rats are omnivores, meaning they eat meat. Although they will eat seeds, leaves, and other plant-based food, many of them would prefer to eat some meat if they can find it. They will look through trash or seek out pet foods that have meat content in them.
  • Shelter. Although rats can find places to live outside of a garage, your little car shelter/storage unit offers them protection from the elements and gives them a home.
  • Safety. A garage is a space with few, if any, predators, such as owls and birds of prey like hawks and eagles.

Although a garage provides shelter and safety, most likely, it is the smell of food that has a rat sniffing around your garage. Rats have a horrible vision (about 20/600).

However, they have an amazing sense of smell. Their tiny noses have between 500 and 1,000 olfactory receptors. Around 1% of a rat’s DNA is devoted to detecting odors.  

In addition, rats have a second organ that detects odors. The VNO, or vomeronasal organ, receives these scent molecules from the moisture in their mucus. Although the VNO mainly detects pheromones, a rat uses the information it receives through the VNO in selecting their food to consume.

How Do You Know You Have Rats?

The most apparent sign of rats is their droppings.

For reference, back when we had a rat problem at my apartment (common in older city houses with unfinished basements), I had found one of these presents on my bed after getting back from an overnight wedding. AKA, that’s a rat dropping (picture above).

Rat droppings, however, are not generally found on your bed. Instead, they will most commonly be found against walls, storage cabinets, or around food sources. Basically, they’ll be in a place where the rat feels comfortable and is likely to stop and do their business.

Another way to tell if you have rats is gnaw marks or shavings of wood. These are a sign that a rat is chewing on a door or baseboard. Rats chew because their teeth are continually growing, and they need to chew to keep them sharp and short.

Rats do not clean themselves like cats do, so as they run against walls, they will leave oily marks along the baseboard or any other surface their bodies come in contact with.

Oh, and rats also like to chew electrical wire.

Why Do Rats Chew Wire?

Rats seem to love wire, but why is that?  

First, rats do not go looking for wires. Instead, the places they like to hide have wires in them. Also, the wire has an advantage over wood, plastic, or vinyl. Because the wire is flexible, rats can better control it as they chew and keep their teeth sharp. 

Cars Are an Unexpected Source of Food

If the spot where you park your car has shavings that are not rat droppings, rats could be chewing away at your car. Car manufacturers are using more plant-based materials in their cars.

  • Soy foam is used in seat cushions and headrests of every Ford car.
  • A Toyota Prius contains a “plastic” made from corn and sugarcane.
  • Coffee chaff (the skin of the coffee bean) is beginning to be used in cars

But the biggest culprit is soy-based wiring, which is commonly used in many cars. Although car manufacturers claim that the rats do not care whether the wiring is soy-based or not, many car owners are having none of it. Both Honda and Toyota have been party to class-action lawsuits.

Whether rats are hiding in your car and chewing the wiring because it’s plant-based or chewing on the wiring because it’s there, this is one more reason to rat-proof a garage.

How Do You Keep Them Out of a Garage?

If you have not found any signs of rats, this is the perfect time to rat-proof your garage! Okay, so here’s what you should do:

Make Sure Your Yard Is Not a Good Place for Them to Live

  • Don’t give them shelter. Piles of trash, wood, or brush make good shelter, so remove them. Grass makes an excellent hiding place, so keep it mowed. 
  • Deprive them of food and water. Cutting down on your water bill is not the only reason to fix water leaks. Although rats get much of the water they need from food, access to water gives them a reason to hang around. Keep bird and pet food either indoors or store it in hard plastic or metal containers with sealable lids.
  • Make sure your woodpile is in the light. If your woodpile is inside your garage or just outside it, make sure that it has at least 1 foot off the ground. Next, you’ll want to TIGHTLY wrap your woodpile in a waterproof tarp to help keep rats out. If rats have trouble getting into your woodpile by not having an easy access point into it, then you’ll be in the clear.

    Make sure to watch for chew marks in your tarp in case rats find a way into your woodpile.
  • Don’t give them shady places to hide. Rats like to stay in the dark during the day. Ivy, overgrown junipers, or other hedges that do not allow any light in make for great hiding places.

This is one of the most overlooked steps to keep rats out of your garage. If rats do not have places to sleep during the day, they will move to someplace safer.

Replace the Garage Door Bottom Seal

The most obvious entry place for a rat is under the garage door.

Let me tell you, four-legged rodents are SO very resourceful in getting through that bottom seal.

A standard garage door is eight to nine feet wide, leaving plenty of places for a rodent to find a gap to squeeze through. If you can slip your fingers underneath the door seal, you have found an opening that a rat or mouse could use to get inside.

What you should look for in a replacement seal:

  • Rodent tooth proof. Rats will chew right through vinyl, foam, or felt weatherstripping. 
  • Ability to withstand temperature extremes. Check the temperature rating on the seal so it doesn’t get melted if it’s on pavement
  • Durability. After all the time and money you will spend on replacing the seal, you want something that lasts. That’s why you should avoid foam weatherstripping. Sure it will be easy to install. But a year or two from now, you will need to do it again.  

A product that meets those criteria is the Xcluder X2 Rodent Proof Garage Door Seal Kit. The seal has three layers of protection. The outer layer is constructed from heavy-duty rubber. Next is a stainless-steel screen, and then it has an inner core of a fill fabric that is similar to steel wool.

A brush seal adds a final layer of protection from rodents, insects, and the elements. Installation should not be difficult for an experienced DIYer. Check out this video to see how to install the Xcluder.

Check the Door’s Weather Seal

Another frequent access point is at the bottom of a garage door’s weather seal. These seals are made of vinyl, and rats and mice often chew through the plastic to make an entry hole.

An easy solution is the Garage Door Rodent Guard by the Rickford Company. The guard is a 6-inch long, v-shaped metal that is secure and easy to install. Watch this two-minute video to see how quick and easy installation is.  

Check Around Spigots, Vents, and Anything Else Sticking Out of the House

Rats spend a lot of time looking for places to enter, and they are not picky about where, as long as they can access it.  

One of the most common places that rats enter is through dryer vents. If the vent is not tight against the wall, a rat can squeeze past it and enter the wall. Or, a rat can chew its way in through the vent. Replace a plastic vent with a metal one or put a metal vent guard over the vent.

This Stainless Steel Universal VentGuard looks very attractive because the stainless steel has a white finish. If you prefer something mounted flat, you might like the Imperial 4″ Premium Intake Cap. ” Either product is easy to replace.

Seal Where Brick and Siding Meet

Mice and rats have a difficult time climbing up siding, but the same is not true for concrete and brick. The point where your siding meets the brick or retaining wall is another possible entry point for a rodent.  

To start this project, you will need some sealant, such as Quad 10 Ounce Advanced Formula. An ideal sealant will be mildew resistant, paintable, and will not need a primer to adhere to surfaces. 

  1. If you find a gap larger than your fingernail, then you will need a foam backer rod. Also called filler rope, the backer rod comes in sizes from ¼ to 1 inch.  
  2. Next, you’ll want to check underneath the vinyl where it meets the brick and check for gaps 
  3. In areas where the gap is larger than your fingernail, push the backer rod (filler rope) in using a paint scraper.
  4. Avoid using the filler rope in areas where the gap is small.
  5. Lastly, use a caulking gun to fill in the gaps.  

Check Seals Around Doors and Windows

If your garage has a side door, check the seals around that as well. Weatherstripping a door not only keeps out rats and other critters, but it also provides protection against moisture and can cut down on drafts.

You can use vinyl weatherstripping, like this Hawwwy Insulation roll. Depending on the size of the gap, another option would be a door gasket. Rats can chew through vinyl, but not the aluminum that is typically used in door gaskets.  

Door gaskets include several options for the seal—vinyl and magnetic. If your family uses a side garage door frequently, then a magnetic seal is something to consider.  

Remember to check the sweep under the door also. Something like the Frost King Drip Cap Door Bottom Sweep is an excellent choice for exterior doors. 

While you are weatherstripping, do not forget to check around the windows, either. Make sure there isn’t a gap where the siding and window frame meet.

Cut Back Tree Limbs

Rats are great climbers; however, they have difficulty climbing up vinyl siding. Once a roof rat realizes it will not be able to climb up using your siding, it will look for trees close to the house. If your trees have limbs hanging over the roof, the rat has an easy way to get there. And once it is on the roof, it will begin to look for ways to enter. 

Cutting back tree overgrown tree limbs might be a job for a professional. Since arborists are not cheap, some motion-sensor exterior lights might work as an inexpensive solution. Rats like to operate in the dark. Light would expose them to owls and other prey so that they might stay away.  

If you decide to have someone come out and trim back your trees, check out the Arbor Day Organization site. You will get recommendations for arborists in your region, as well as other information regarding tree care.

Use a Rodent Repellent

Search the internet, and you will find countless DIY recipes for repelling rodents. Many of them are based on the idea that since rats have strong senses of smell, an odor they dislike, such as naphthalene, will repel them.  

Peppermint oil, bergamot, eucalyptus, and citronella all contain odors that rats may dislike. However, evidence that they deter rats is inconclusive at best.

If you want to try a natural rodent repellent, then try Fresh Cab Rodent Repellent. Application is easy, it is non-toxic, and the product meets EPA standards for indoor and enclosed areas use. Fresh Cab recommends that homeowners place one pouch every 125 square feet and claim the smell lingers for three months.  

Finally, Fresh Cab offers a money-back guarantee if their product does not work, which is more than you will get back from a bottle of peppermint oil.  

Monitor You Garage!

The goal is to exclude rats from being able to get into your garage. Even after you rat-proof your garage, it’s important to continue to check that they have not taken up residence. Look for tell-tale signs, such as oil marks against the baseboards, chew marks, or rat droppings.

Bottom Line

Your goal in rat-proofing your garage is to exclude them from getting into the garage. Start by inspecting for points of entry, and then seal off those points to prevent access. Keep your garden tidy and trim bushes and trees, so they don’t become havens for rats and other rodents. If you must keep food in the garage, store the food in metal containers.  

And remain vigilant—a rat would like nothing more than to take up residence in a place that provides security and protection from the elements. 

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