How to Safely Remove Critters in Your Chimney


If you’ve got a chimney in your house, then you’ve probably encountered at least 1 member of the wildlife community who’s tried to use your chimney as a new home. 

A chimney offers a safe and warm place for birds, bats, rodents, squirrels, and various types of insects. And your chimney is an obvious go-to during the warmer months when your chimney goes unused.

The longer you go without maintaining your chimney, the more likely animals are to find a way in.

Pests can damage the inside of your chimney, and bring unwanted disease, ticks and fleas into your home.

Here are the 5 common types of pests you might find in your Colorado chimney and how to safely and humanely get rid of them.

Birds or Bats

If you’ve heard flapping and rustling coming from your fireplace, you’ve probably got birds in your chimney.

It’s possible but unlikely that it’s a bat, as bats are more likely to be found in older chimneys than modern ones.

Birds and bats can carry diseases such as histoplasmosis and rabies, so you don’t want them to enter your house through your chimney.

The easiest way to tell if it’s a bird or a bat is to head outside at dusk and watch your chimney near dusk. Birds will come into your chimney when the sun is going down, while bats will head out at this time.

Chimney swifts are a migratory bird that have been spotted in Boulder County, so it’s possible this is the type of bird in your chimney. In this case, you can typically wait them out. Chimney swifts will roost in the summer but head south as it gets colder. These birds typically won’t be around by the time you need to use your fire place.

What to do:

Have your fireplace cleaned in the fall to clear out any nests (which’ll stink when they burn and also possibly block your flue). Then get your chimney capped to prevent the birds from returning in the spring.

Bats can squeeze through bird screens and small cracks in your chimney. The best cure for bats is prevention. Chimney maintenance can minimize the places where bats can get in. Your chimney cleaner can also install a combination damper & cap to keep bats out.

If you’ve got bats in your chimney, call an animal removal service (often a chimney cleaning service offers this).


Squirrels may get trapped or build nests in your chimney. If you hear scrambling and tell-tale squeaks, chirps, or barks, chances are you’ve got a squirrel in your chimney (or even a whole family!)

Squirrels can enter your home through the chimney and cause a lot of damage and spread disease. And their nests will likely block the flue and create a fire hazard inside your chimney.

If the critter is making a lot of noise, it’s probably trapped and trying to get out. Your best approach to remove it humanely is to provide a way for it to escape.

What to do:

First, close off your damper. If the squirrel is in the fireplace itself, make loud noises to scare the squirrel up into the flue, then seal the damper. Then lower a thick rope (3/4” or thicker) down the length of the chimney. The squirrel will likely climb out within a day.

If this doesn’t work or if squirrels have decided to turn your chimney into a home, it’s time to call animal removal.

A good chimney maintenance service will be able to remove the animals, clean out anything they’ve left behind, and install a proper cap to hopefully prevent them from coming back.


A chimney is quite a bit like a hollowed-out tree, which means it’s a great safe place for raccoons to raise their young. These animals are more likely to enter an uncapped chimney in the winter or spring.

Raccoons will either make noise, leave droppings in your fireplace, or you can see the mother leaving and entering your chimney at night.

What to do:

Most raccoons will eventually move out on their own. But in the meantime, they can damage your chimney and carry rabies and other diseases.

If you don’t want to wait it out, call an animal removal service. A chimney sweep can clean out their debris and install a chimney cap.

Make sure your chimney is animal-free before you close it up or install a cap. You don’t want to trap the raccoons in your chimney and risk killing them. You can shine a flashlight up your chimney from the fireplace and down from the roof to check that it’s clear.

Rats & Mice

If you hear scratching and rustling sounds in the chimney or in the walls of the house, you might have a rodent infestation. You may also find their droppings or see evidence of them visiting your pantry by holes they chew in food packaging.

A strange smell coming from the fireplace when you have a fire is another tell-tale sign you’ve got a pest. A nest or dead rodent burning up in the flue will likely give off an un-pleasant funk.

Animals like this can squeeze into your chimney through cracks in the mortar or other holes, even very small ones.

What to do:

Have a chimney maintenance professional identify and seal critters off from entering your home. A chimney cap can help keep these critters out once you’ve gotten rid of them.

Remember to always shut your damper when you’re not using your fireplace to help keep rodents in your chimney from getting into the rest of the house.

Finally, keep your house clean! Rodents are attracted by accessible food — especially the little crumbs that fall under your fridge or behind the oven. Food should be kept in sealed containers in the pantry, and sweep up crumbs regularly.

If none of the above seems to work, mouse or rat traps are probably your best ap-proach.

Rat & mice traps (an electrical trap is a good go-to for bigger rodents like rats) should be placed around any possible entry point to your home, as well as behind walls and in basements and attics.

Bait the traps with food like meat, peanut butter, cheese, or dried fruit. Check the traps daily to empty and reset them as needed.

If you’re still having rodent problem after a week, the animals are probably getting in through an entry point you haven’t discovered. Recheck the house and chimney for entry points and try again. Call in a pest removal service if you’re still getting stumped by the critters.

Once you’ve cleared the rodents, get your chimney cleaned to make sure it’s free of any nesting debris and droppings they may have left behind.

Wasps & Bees

Got bees or wasps flying around inside your house, and have no idea how they’re get-ting in? Try checking the chimney.

The airflow generated in a chimney flue can make chimneys an attractive spot for bee-hives and wasp nests.

What to do:

The first thing to do is check your chimney by using a flashlight to see if there’s a nest or hive.

Wasps can be killed off with a spray poison. You may need to spray this in from the roof to reach the nest, depending on where it is in the chimney.

The spraying is likely to upset the wasps and give them cause to sting. Make sure to wear thick protective clothing, along with gloves, a face mask, and protective glasses.

Once the wasps have been killed off, you can have a chimney cleaner remove the nest.

If you’ve got bees in your chimney, it’s important to try to remove them as humanely as possible, as many types of bees are endangered species.

Call around to local pest control companies to see who has specialize in humanely removing and relocating bees, rather than simply exterminating them.

You should do this as soon as notice the bees in your chimney, as it’ll likely be easier to relocate them when there is less comb that needs to be removed.

Once the bees have been removed, call a chimney cleaner to clean out any remaining wax and honey.

Pro-tip: Whatever you don’t, don’t light a fire while wasps or bees are in the chimney. A wasp nest will cause blockage that could lead to a fire. And beeswax can liquefy and catch on fire, which could endanger your entire home.

Most pests are getting into your chimney because of improper maintenance and insuf-ficient cleaning. A chimney cleaning service can identify places where pests are get-ting in, install various types of caps to minimize the chance of invasion, and clean up the mess these creatures leave behind.

Sunshine Chimney Cleaning, a division of Boulder’s General Services Corporation, is approved by the Better Business Bureau and the Boulder Chamber of Commerce and can help you with keeping your chimney clean and pest-free. Request a quote today >