Roof Rat Infestation: Causes, Symptoms and Solutions

A roof rat infestation is a problem no homeowner wants to have. Roof rats are a common type of rat that get their name from their tendency to seek shelter in the upper part of buildings. They are smaller than a common subway rat, which allows them to sneakily gain entry into your home. Don’t let the name deceive you – roof rats can also be found in other parts of your home and in outdoor spaces. If you are a homeowner, it is important to be aware of roof rats, the problems they cause, how to prevent an infestation, and how to get rid of a roof rat infestation. 

How Do Roof Rats Get Into Your Home? 

Roof rats are naturally gifted climbers and prefer having their nests up high. They are known to use tree limbs, vines, and power lines to climb up and get into homes. In some cases, roof rats can also climb directly on your exterior stucco to gain entry into your home. While roof rats are not as small as mice, they are able to easily get into an opening that is about the size of a quarter. Generally, roof rats seek shelter in homes for protection from predators and to look for food/water sources.

Are Roof Rats Harmful? 

Roof rats are harmful to your health and home, so if you have an infestation, it is something you should take care of immediately. 

A roof rat infestation can detrimentally affect your health. They carry fleas and also diseases such as typhus, infectious jaundice, rat-bite fever, and trichinosis. If you have them in your kitchen, they can also cause food poisoning by contaminating food or counter spaces where you prepare food.  If you want to learn more about the harmful effects of roof rats on your health, The University of Arizona published a paper discussing the pathogens they carry.

Roof rats also harm your home. They gnaw on wooden structures such as wood beams and other important parts of your home. Roof rats also chew on pipes, trample down on insulation, and chew on wires. If they get to your electrical wires or pipes, roof rats can cause many hazards and damage to your home.

How do I know if I have Roof Rats? 

If you have a roof rat infestation, and require rodent proofing services, there will be signs. You won’t usually see the roof rats as they are nocturnal, but as they forage for food, they will leave signs of their presence. 

The most obvious sign that they leave are droppings, which are about 0.5 inches long. If you come across these, you should clean them up immediately using a strong disinfectant since their droppings are known to spread disease.

Other signs of a roof rat infestation include gnawing or scratching noises in the attic or walls, damage to electrical wires from gnawing, hollowed out fruit if you have fruit trees in your yard, the presence of nests in the insulation of your home, and gnaw marks around your home’s roof. If you have a dog or cat, the presence of roof rats will likely cause them distress and agitation. If your animal starts randomly acting strange and you’re noticing gnaw marks around, it is likely you have a rodent infestation that could be roof rats.

If you are seeing signs of a roof rat infestation, call a trusted exterminator immediately. Once roof rats are inside your home, the population is known to grow quickly. A female roof rat can have a litter of 5-8 babies up to 3 times a year. 

How to Prevent a Roof Rat Infestation

No home is immune to a rodent infestation, which is why it is important to take precautionary measures to avoid having roof rats come in and completely disrupt your home. To prevent an infestation, you should look for and seal up any holes or cracks that are larger than a quarter. Additionally, all windows and vents should have screens on them so that the rats can’t sneak through. Since roof rats are very adept climbers, you will want to ensure your trees and shrubs are trimmed away from your home so they do not have easy access to your space. It is also recommended to eliminate sources of water that the rats would be attracted to such as leady sprinklers, birdbaths, and leaky pipes.

Another important aspect of rodent prevention is to be mindful about food they may be able to access. Roof rats are always searching for food sources, so as your first line of defense make sure any fruit that has fallen from trees is cleaned up and your garbage cans are tightly sealed. Inside, you should ensure dry food and pet food are in sealed containers so that the rodents cannot access it. 

Some people use ultrasonic repellents to deter rodents like roof rats from entering their homes. Essentially, these devices emit a high-frequency sound that is extremely distressing for rodents but does not bother humans and most pets. If you have a hamster or guinea pig, be mindful about where you place this device so you are not causing them any harm. 

How Do I Get Rid of a Roof Rat Infestation?

If you are seeing signs of a roof rat infestation, we recommend calling a trusted exterminator in your area who can conduct a home inspection and come up with an infestation treatment plan for your home. 

If you are more of a DIY person, there are certain actions you can take to get rid of the infestation. You can use a bait and trap method to get rid of your roof rat infestation. It is recommended that you use dried fruit, nuts, berries, peanut butter, or an item such as dental floss that is an attractive nesting material. One thing to note is that you should avoid setting traps and placing food in the attic of your home as it could have an unintended effect of attracting more roof rats.


Best bet would be avoiding traps and food in the attic, only at extreme situations you should place traps in attic only to find the rats entry point to the attic Because roof rats are cautious creatures, to lure them into the trap, it is recommended that you put out the bait for a few days without setting the trap so that they trust it as a safe food source. 

For traps, you have the option of a traditional snap trap (you know the one) or a more high tech electronic trap. The electronic traps are considered to be more humane as they use a high-voltage shock to take out the rat. Electronic traps are a great option because they are reusable, easily disposable, they have a blinking light that indicates a rat is in there, and most importantly, they are safe to use around pets and kids.

Once you have gotten rid of the roof rat infestation, sanitize everything and follow the roof rat prevention tips recommended by experts and enjoy your roof rat free home.