Squirrels are great climbers, so they easily can climb onto your house and chew through a wooden gable to gain access to your attic. Attics are one of the most favourite nesting spaces for squirrels because they are sheltered and packed with insulation, which is the perfect nesting material to keep them warm. Female squirrels give birth twice a year, so this is the most common time for them to seek a warm shelter. Once the squirrels gain access to your attic they can create huge damages. They can chew every electrical wiring, which can cause fire, also they can chew through PVC, which can lead to flooding. Unfortunately, home insurance will not cover that type of damages caused by rodents. The most common way to start noticing squirrel issues is to hear them chewing or crawling around the walls.