What to Do About a Raccoon in Your Chimney

Why raccoons pick chimneys

An uncapped chimney looks like a hollow tree to a raccoon. They climb brick easily, especially on older chimneys with deep mortar joints, and can work their way down a clay-lined flue to the smoke shelf, the flat ledge just above the damper at the back of the smoke chamber. It is dry, dark, out of the wind and out of reach of other animals.

In late winter and spring, the raccoon in the chimney is usually a female looking for a safe place to have and raise her young. Suburban neighborhoods in New Jersey, Westchester, Long Island and around Philadelphia see this every year, and so do tree-lined blocks in the city. That changes how the problem is handled, because removing the adult alone leaves the young behind.

What a raccoon in the chimney sounds like

Raccoon noise is heavier than bird or squirrel noise, and it follows a night schedule. Listen at the fireplace in the evening and through the night, and again around dawn when the adult comes back.

• Heavy scratching and climbing, mostly from dusk through the night
• Thumps as an adult drops onto the smoke shelf or the damper
• Chattering, whining or chirping from the young, often around feeding time
• Growling or hissing if the animal is disturbed
• A strong animal smell from the fireplace in warm weather

Telling it apart from other animals

Birds are busiest in daylight and sound like fluttering and light scratching; chimney swifts in summer make a constant twittering. Squirrels run in short daytime bursts and often get stuck on the damper. Bats are quiet apart from faint squeaks and rustling at dusk. A raccoon is the heavy one: slow, deliberate climbing at night, and the unmistakable chatter of kits.

Knowing which animal it is matters because the response differs. A trapped bird or squirrel needs a way out. A raccoon with young needs time and a careful sequence before the chimney is closed.

What not to do

Lighting a fire or putting smoke into the flue seems like a quick fix, but it is the worst one. The young cannot climb out, the mother may refuse to leave them, and a nest of leaves and debris on the smoke shelf can catch fire right where the chimney is hottest. Opening the damper to look invites a frightened adult into the room.

Do not cap the chimney while an animal is inside either. A trapped raccoon will try to get out through the damper or the fireplace opening, and young left behind will die in the flue, which brings its own smell and cleanup. Moth balls, ammonia rags and similar home remedies dropped down the flue add fumes to the house without reliably moving the animal.

What to do right now

Close the damper if it is not already closed and you can do it without reaching into the firebox. Close the glass doors or put a solid screen across the opening, and weigh it down. Keep children and pets out of the room. Do not try to reach up the flue or pull out nest material.

Then call for help. Rules on handling wildlife vary by state, and some situations call for a licensed wildlife control operator. A chimney company that handles animal removal will know when to involve one. If anyone has been bitten or scratched, contact your doctor or local health department promptly.

How it gets resolved

The first step is to confirm what is there and whether young are present, usually by listening, looking at the top, and checking the smoke shelf from below with a light. When a mother has young, the usual goal is to have her move them out on her own, which she often does once the nest stops feeling safe. When everything is out, the top is closed so she cannot come back.

Then comes the cleanup. Raccoons leave nest material, food debris and droppings on the smoke shelf and damper. That material is removed with protective gear, the flue is swept, and the damper, smoke chamber and liner are checked for damage from claws and moisture. Handling the debris bare-handed is a bad idea; leave it to the crew.

• Confirm what is there and whether young are present, which decides the method and timing
• Let the mother move the young out once the nest feels unsafe, so no animals are left trapped
• Fit a sturdy cap after all are out, so she cannot return the same night
• Remove the nest and droppings, sweep the flue and check the damper, which removes the fire and odor risk

Damage a raccoon can leave behind

Raccoons are strong. They tear loose or rusted caps off, pull at mortar around the flue top, and rip foil-faced insulation or bend damper plates. Nest material packed on the smoke shelf blocks the throat and can hold moisture against the masonry. In a flue that serves a boiler or water heater, a nest can block the exhaust path and push fumes back into the house, which is a carbon monoxide risk; keep alarms working and dial 911 or the utility if one sounds.

That is why the cleanup ends with an inspection rather than just a sweep. The damper may need replacing, the crown may need patching where the animal pulled at it, and the smoke chamber may need cleaning of odor-carrying debris.

Keeping them out for good

A raccoon is strong enough to tear off a thin or loose cap, so the cap needs to be sturdy stainless steel, sized to the flue or the whole crown, and anchored firmly so it cannot be pried up. Each open flue on the chimney needs one, or a single multi-flue cap that covers the whole top. Branches hanging over the roof make the chimney easy to reach, so trimming them back helps. If the crown or flashing has gaps, those are fixed at the same time.

Check the cap from the ground once or twice a year, especially after storms and in late winter before the nesting season starts. A cap that sits crooked, has a bent screen or shows a gap at the base has usually been tested by an animal already, and fixing it before spring is far easier than another removal. If you have a fireplace you never use, a top-sealing damper or a full cover is another way to close the flue for good.