Raccoons are more likely to visit in winter and spring, but they can and will get inside at any time of year. In spring, a mother may choose an attic or chimney as a safe spot for giving birth and raising her young.
Raccoons in the attic
As intelligent problem-solvers with great dexterity and determination, raccoons often find their way into attics at entry points where different building materials join. This might be where dormer junctions occur, where unpainted trim board creates structural defects, or where the building material itself is pliant, enabling them to push their way past, as is easily done with some plastic soffits.
An ounce of prevention
Prevention—through routine inspection and repair—is the easiest, cheapest and most humane approach. If your attic is already occupied, keep in mind that if there are baby raccoons present, they will be leaving with their mother once they have been weaned and are old enough to follow her on nocturnal forays (about six weeks of age).
They will typically take up residence in alternate den sites during the time in which their mother is teaching them how to cope on their own. If you can monitor the attic and determine that they've moved out, then repairs or exclusion can be done to prevent reentry.
Raccoons in the chimney
When a mother raccoon sees an uncapped chimney, she sees a perfect nursery. It’s a safe and sheltered place to give birth to and raise her young until they are able to get around on their own.
The fireplace chimney is usually preferred because the horizontal "smoke shelf " is a convenient size to nestle with her kits, but she may also use the chimney venting a furnace.
Never use smoke or fire to drive animals out of chimneys! You will kill young raccoons not mature enough to climb and may even kill adults.
The good news for people who don’t welcome a nursery in their home is that the family will move out on its own. If you know you're dealing with only adult raccoons, you can use humane harrassment techniques to get them to move out.
Put a cap on it
Never attempt to install a chimney cap until you are certain that all animals have vacated the chimney.
Shine a light up the flue to make sure there are no raccoons on the damper and smoke shelf. Next, check the chimney flue from the roof (or have a chimney sweep do it) to make sure no animals are present.
As soon as the raccoons are gone, call a certified chimney sweep to clean your chimney of all nesting debris, and install a chimney cap.
If you're a DIY-er, be sure to purchase an approved chimney cap and follow installation directions carefully to prevent future visits of the animal kind.
Check with a local certified chimney sweep about any local building codes regarding cap installation. For information on good venting practices, check out these recommendations.
Call a professional
If more immediate and direct intervention is required to evict raccoons, then we strongly recommend hiring professional assistance. Evicting a raccoon can be difficult. There are potential safety risks to the homeowner and humane concerns for the raccoons if the eviction isn’t done properly. If you decide to solve the problem yourself, read our general guidelines for evicting and excluding raccoons.