Birds, raccoons or squirrels in your chimney: what to do in Pennsylvania

Updated November 10, 2026 · KeystoneProGuide editorial team

What should you do if something is living in your chimney?

Do not light a fire, and find out what it is before anyone removes it. The right response depends on the animal. A nest of chimney swifts is protected by federal law and has to be left until the birds migrate. A raccoon or a squirrel comes under Pennsylvania's wildlife rules, and the season matters there too. In every case the flue should be inspected and cleaned before it is used again.

Why is an animal in the flue a safety matter?

Because a nest is a blockage. The Consumer Product Safety Commission warns that birds, other animals and insects can build nests in vents over spring and summer, causing blockages that send deadly exhaust into the home. The Centers for Disease Control and Prevention gives debris in the chimney as the reason to have it checked or cleaned every year. On the fireplace side, the University of Missouri Extension lists bird nests among the obstructions that cause smoky fires.

This applies to a furnace flue as much as to a fireplace. CSIA, the trade's certification body, says a gas flue can stop working because of bird nests or other debris.

What if the birds are chimney swifts?

Then the law is clear and so is the remedy: wait. The U.S. Fish and Wildlife Service says the chimney swift is a migratory bird protected by the Migratory Bird Treaty Act, so harassing, injuring or killing swifts, their eggs and their nests is illegal.

What the Service says about them:

They arrive in the United States in March or April and leave in August or September. The Audubon Society of Western Pennsylvania gives local dates for its region: arrival around the third week of April, departure around the first week of October, with nesting typically in June and July.
A pair builds a small half-saucer nest of twigs glued to the inner wall, and pairs tend to return to the same chimney each year.
They do no structural damage to the chimney and pose no fire or health hazard, in the Service's words.
The loud part is short. Nestlings can be heard begging for food for about three weeks.

And what it tells homeowners to do in the meantime:

Do not use the fireplace, or the furnace if it shares that flue, while swifts are present.
Keep the fireplace damper closed after the heating season, so birds cannot fall into the firebox or get into the house.
If the noise is a problem, put foam rubber above the damper and remove it later. The Service says not to use fiberglass insulation for this.
If a nestling falls, contact a licensed migratory bird rehabilitator.

Once the birds have gone, have the chimney cleaned. The Service says cleaning off creosote every year is extremely important for fire safety, and that for most of the country the time to do it is between September or October and March or April. The western Pennsylvania Audubon society suggests March, after winter use and before the swifts return.

What if it is a raccoon, a squirrel or a bat?

State rules apply, and the Pennsylvania Game Commission's guidance turns on two points: the time of year and the species.

Time of year. The Commission says exclusion, meaning blocking the way in, can work for bats, squirrels and raccoons, but warns against doing it while young are present. For maternity dens of raccoons and squirrels its advice is to let the young leave first, and it says waiting until fall is a good bet. Shutting bats out in summer, it adds, forces those trapped inside into the living quarters.

Species. Raccoons and bats are among the animals the Commission calls rabies vector species, which should not be relocated like other wildlife. A homeowner who traps one has to choose between dispatching it and releasing it, and risks a bite or a scratch either way. Homeowners may not trap migratory birds or threatened or endangered species at all. Traps must be checked daily, and the Commission asks residents to contact its region office before trapping nuisance wildlife.

It lists hiring a wildlife pest control agent among the options when animals move into a house, and a raccoon in a flue is a case for one.

What does removal cost?

The cost surveys disagree widely.

Angi: $200 to $600 to free an animal trapped in a chimney.
HomeAdvisor: $180 to $560, with a note that protected species such as bats may require special permits.
Fixr: around $100 for a small, easily removed animal and up to $700 for a harder job.
HomeGuide: $600 to $1,500.

These are national figures and none is specific to Pennsylvania.

Who do you call, a chimney sweep or a wildlife service?

It depends on whether the animal is still alive in there. A live mammal is a job for a wildlife pest control agent working under the Game Commission's rules. An old nest, the debris it leaves and the inspection that should follow are a sweep's work. For swifts, the Fish and Wildlife Service suggests looking for sweeps, masons and inspectors who know how to protect the birds. Clearing out a swift nest that is in use is the kind of disturbance the federal law forbids, so that job waits until the birds have left.

How do you keep animals out afterwards?

The ordinary answer is a cap. The Game Commission gives a house without a chimney cap as its example of one that attracts wildlife, and This Old House describes a cap as the part that keeps rain, debris and animals out of the flue. Angi prices a replacement cap at $75 to $500.

There are two exceptions, both from the Fish and Wildlife Service. If you want swifts to keep using the chimney, the Service asks you not to cap it and suggests other measures against climbing animals: trimming back overhanging branches and wrapping a 2-foot-wide band of metal flashing around the outside of the stack near the top. And if the flue has a metal liner, the Service says it should be capped, because birds cannot cling to metal and become trapped.

Chimney caps, crowns and flashing covers caps in detail. What a blocked flue can do is explained in carbon monoxide and your chimney, and how often a chimney should be swept has the calendar. Local businesses are on the chimney sweeps directory page.

Sources

Chimney Swifts, U.S. Fish and Wildlife Service
Audubon's Chimney Swift Tower Program, Audubon Society of Western Pennsylvania
Nuisance Wildlife, Pennsylvania Game Commission
Install a carbon monoxide alarm in your home: CPSC Urges Annual Furnace Inspection to Prevent CO Deaths, U.S. Consumer Product Safety Commission
Carbon Monoxide (CO) Poisoning Basics, Centers for Disease Control and Prevention
Homeowner Resources, Chimney Safety Institute of America (CSIA)
Chimneys for Wood Stoves, University of Missouri Extension
How Much Does Chimney Repair Cost?, This Old House
How Much Does a Chimney Sweep Cost? [2026 Data], Angi
How Much Does a Chimney Sweep Cost in 2026?, HomeAdvisor
How much does a chimney sweep cost?, HomeGuide
How much does it cost to have a chimney cleaned?, Fixr