Bats only need 1/4 to 3/8 inch of a gap to gain entry. That works out to be the approximate width of a No. 2 pencil. Bats will not chew or scratch to create entry into the home. It is often gaps that are left open during the construction or settling of the home that allow bats to enter.
Common areas bats enter homes are: louvered gable vents, ridge vents, chimney flashing, roof lines, eves, and dormers.
A thorough inspection by a Propestmen Bat and Mice expert can determine active and potential entry points for bats.