One of the most common chimney issues that homeowners encounter is having wildlife nest inside. Your home's chimney is an ideal shelter that's warm, dry and safe. One of the most common tenants to find inside your chimney is squirrels. After all, they are used to living in the hollows of trees. Your chimney can resemble a hollowed out tree to a squirrel, and once they climb in, it can be hard to get out unless the walls are masonry.