Attic Insulation

Signs of a Rodent Infestation in Your Attic

Have you seen signs of rodent infestation around your home or business? If you’re concerned about sharing your home with an unwanted guest, keep an eye out for common signs of an infestation.

Rodents can damage your home’s insulation. The team at SoDak Insulation is here to help. If rodents have done a number on your attic insulation, give us a call today.

What Are The Signs Of Rodent Infestation?

Rodents leave a variety of clues when they invade your home. An active infestation can be spotted with your eyes, ears, and even your nose.

If you have rodents in your attic, they are likely in other parts of your home as well. Keep an eye out for these telltale signs as you inspect your attic and the rest of your home.

rodent looking through hole in the attic wall

Rodent Droppings

One of the most definitive signs of rodent infestation is the discovery of rodent droppings around the home. 

If you have spotted small brown or black pellets around food packages or near baseboards, you have a rodent infestation.

Mice and rats have similar droppings. Mouse droppings have pointed ends, are smooth, and are between an eighth and a fourth of an inch long. Rat droppings are a bit larger and often have more squared-off ends. 

Always wear gloves and a dust mask when cleaning to avoid getting sick.

Gnaw Marks

Rodents have strong teeth that keep growing throughout their lives. Gnawing helps them keep their teeth in check.

Mice and rats use their teeth to gain access to your home. Once inside, they happily chew their way through walls, electrical wires, and food containers.

Rodent gnaw marks look like very small nibbles with evenly spaced, tiny parallel lines. A house mouse may leave telltale gnaw marks on your walls, furniture, or the bottom of doors. 

sign of rodent infestation is a rodent on your kitchen counter

The Smell Of Urine

Mice have a peculiar smell that resembles stale urine or ammonia. The odor helps them to mark their territory.

If you discover an animal smell when you open a cabinet or closet, you most likely have a rodent.

Rub Marks and Tracks

When rats move around your home, they often leave dark smudges on the baseboards. Rats have oily fur that leaves a residue on surfaces. They like to stick with familiar paths and keep near walls, and their tracks can be seen with a close look.

In the attic, your insulation leaves a clear trail where mice have been. Mouse pathways in your insulation look like small, 1- to 2-inch deep hallways.

A Dead Body

You found a body in your pantry. Did you think, “Oh good, it’s dead”? 

Sadly, if there was one mouse in your house, there is very likely more than one mouse in your house.

Mice follow the scent of other mice. That one critter you found very likely has brothers and sisters living in your walls.

Don’t wait to meet the whole family. 

Scratching Noises

Rodents don’t trim their toenails. One of the signs of rodent infestation is scratching noise from inside your walls. 

Rodent sounds are most noticeable at night when they are most active and your home is the quietest. 



Rodents love to build nests from shredded paper, bedding, and insulation. Check the dark corners of your home, as well as behind furniture and in cabinets.

What To Do When You Have Rodents In Your Home

You noticed the signs of a rodent and confirmed you have a trespassing critter. Don’t delay: Take steps to remove those rodents right away.

Follow these steps to evict your unwelcome guest:

  1. Attempt to determine how it got into your home. Fix any holes or gaps that could provide access to additional rodents.
  2. Secure any potential sources of food. Food in plastic bags should be placed in containers with thicker walls. Don’t leave the pet food out, either.
  3. Place traps. If you know the animal’s trail, set traps along their path. Bait them with chocolate or peanut butter. 

But remember: Never place snap traps or poison where pets or small children can access them. 

Eliminating unwanted pests can be an unpleasant job. You always have the option to bring in professional help. 

how to keep rodents out of your attic

How To Keep Rodents Out Of Your Home

After you’ve gotten rid of your mice or rats, you’ll want to take action to make sure your home stays rodent-free. Incorporate these steps into your home maintenance to keep the critters out:

  • Walk around the outside of your home and check for any cracks, gaps, or other openings. Mice only need a quarter of an inch to push through. 
  • Fix water leaks. A dripping spigot provides a consistent water source for rodents and other animals. 
  • Place pantry staples in airtight containers. Flour, rice, and other foods are often packaged in plastic bags, an easy target for rodents. Put your pantry foods in stronger, airtight containers.
  • Don’t let garbage pile up. Rodents love human garbage and are drawn to it. Keep your garbage in tightly sealed containers, both inside and outside your home. Have your garbage hauled away at least weekly.
  • Only feed the animals you want to keep around. Pet and bird feeders are easy targets for rodents.
  • Watch for signs of rodent infestation as the weather outside gets colder. Rodent problems get worse in the fall and winter.

Keeping rodents out is much easier than removing them after they’ve moved in.

If Your Attic Has Been The Home Of Rodents, Consider Replacing Your Insulation

Rodents are dirty, stinky, and sometimes even dangerous. After you’ve evicted them, your home may need clean-up and repairs.

If you had bats, rats, or mice in your attic, your insulation has been their bathroom. This can make your whole home smell bad. 

If you think you might need to replace your attic insulation, contact SoDak Insulation today for a free quote. Our experts will inspect your attic and help you find the best solution for your home. Reach out today.


How Bats and Rodents Can Harm Your Insulation

Bats love houses as much as people do. If given a chance, they will happily move into your attic space. The quiet, dark, relatively warm area is like a man-made cave. 

Bats can fit through an opening as small as ⅜”. Bats can enter your home through gaps around windows, soffits, and sometimes even take up residence behind the shutters. 

To get and keep bats out of your house, you need professional help. A good exterminator will make sure your home is sealed tight. 

Once the bats are locked out, you’ll want to repair any damage they may have done. Again, this is not a do-it-yourselfer job. Even if you aren’t put off by the thought of removing piles of bat guano, consider the fact that those disgusting piles can also harbor disease.

If you save money cleaning your attic only to spend it on medical bills, that isn’t a win.

Don’t try to take care of this yourself. Contact SoDak Insulation for more information about getting your home back to pre-bat condition. They’ll customize a plan that fits your needs.

birds in attic insulation

How Do Bats and Rodents Damage Your Insulation?

Most rodents chew through everything. Rats and mice will chew through walls, insulation, and even electrical wires. 

Bats are not like other rodents. They may push through gaps or rotted siding to gain entry. But they don’t chew their way in like rats. 

So, if bats don’t do damage by chewing, what do they do?

They poop. Unfortunately, even chewing pests poop.

Bats and rodents poop a lot. In fact, controlling for their size, bats poop more than any other mammal. Bats in your attic will quickly result in large amounts of bat guano. 

The smell of all that feces will permeate the entire house. 

Because the guano is protected from the elements (by your house), it won’t decompose the way it would outside. It will release moisture, which can soak through your insulation, ceiling, and walls. 

All that nasty moisture from urine and feces can pool and puddle, running down walls and ductwork. It can cause visible staining on walls and ceilings.

The guano piles get heavier as they grow. Enough guano can buckle ventilation ducting. 

As though that weren’t nasty enough, the guano can also be home to bacteria and parasites. 

Histoplasmosis is a fungal infection. The fungus lives in bat guano, and spores float up into the air when the guano is disturbed. If you breathe in the spores, you can get very sick. 

They can make you and your pets sick. People are often allergic to rodent dander. Bats can also have parasites on their bodies, called bat bugs. 

Are There Bats or Rodents in Your Attic?

If you don’t inspect your attic on a regular basis (and who does?), you probably won’t know about uninvited guests until signs of them reach your living space.  

Keep an eye out for these signs of an infestation:

  • You or your pets may hear them. Dogs and other household pets often have more sensitive hearing than humans, so pay attention if they seem to be pointing at a wall or ceiling. If you hear scratching or squeaking, check your attic or have a professional check it.
  • You can smell feces or ammonia. If bats or rodents are using your attic as a bathroom, the odor will eventually make its way through your whole house.
  • You see bats or rodents near your home.  If they appear to be flying and landing close to your house, or if you find dead bats or rodents on your property, it’s time for an inspection.

Bats like to burrow in your insulation. They travel toward the heated surface, such as the floor of your attic, since the ceiling underneath is in a heated space. 

raccoon in attic

So, How Do We Fix This Problem? 

Before worrying about clean-up, the bats and rodents need to be evicted.

If you know how they are accessing the space, you can apply an exclusion door. This will allow the bats to leave but not to come back in.

Take a piece of netting that is big enough to loosely cover the point of entry. Tack down the netting across the top and sides, but leave the bottom loose. 

The bats will be able to fly out through the gap at the bottom, between the net and the house. When they return, they will not be able to get back in.

Make sure there are no gaps, rotten, or other potential entry points in your attic space, or you may find yourself with bats again.

If crawling around your attic and inspecting every inch of the space doesn’t appeal to you, consider hiring a professional.

After you’ve taken measures to make sure you won’t be hosting any more bats, your attic will need a thorough clean-up. 

  1. Protect yourself with a face mask, goggles, gloves, and long clothing. Remember the spores that you don’t want to inhale. Sweeping or using your home vacuum is not recommended.
  2. Use a sprayer to gently dampen the droppings. This will help keep the dust down.
  3. Clean the droppings with soapy water and paper towels or other cloth that you don’t mind throwing away.
  4. Disinfect all surfaces involved. Use a 10% bleach solution. Spray areas lightly and let the solution sit for ten minutes. Then rinse and dry.
  5. Insulation cannot be cleaned. Remove any contaminated insulation. Secure the insulation in garbage bags before removing it from your attic to avoid contaminating other areas of your house. 
  6. Dispose of the gloves, mask, and cleaning cloths, or wash them in very hot water. 
  7. Shower. You’re going to need it.

Getting rid of other rodents might be a whole other ordeal. A professional might be the best way to go.

After your attic is bat-proof and clean, you will need to replace the insulation the bats destroyed with new insulation. Insulating your attic is a more DIY-friendly project than evicting or cleaning up after bats. 

Don’t assume the DIY route is the least expensive or most efficient. Get a free inspection from SoDak Insulation. We are experienced at returning your home to pre-bat condition.