How do you feel about bats? Some are creeped out by them, most likely due to the different fictional works that make them out to be dangerous and mysterious. In reality, there is much good that bats accomplish, so much so that some have chosen to make bat habitats in their backyard to attract bats to set up a home there.
The average bat will eat as many as 8,000 mosquitos in a single night. That is definitely something that speaks in their favor.
There is, however, a chance that they might set up their home in your attic, leading to unsanitary conditions with the floor covered by droppings and the possibility of them carrying disease.
So, how do you keep them out? You can find the points of entry to your attic and then install a one way excursion device over it so that they can’t get back in after they leave.
Having a light on in your attic will also discourage them since they are nocturnal.