Excluding a Colony From Your House Bats can be excluded from living quarters by covering chimneys and vents with half-inch hardware cloth screens, by installing draft guards beneath doors, and by sealing any other possible access routes, especially around screen doors, windows and plumbing. They do not chew insulation or otherwise make new holes. Their entries can be plugged with silicone caulking, steel wool, or temporarily even with tape. The bats must emerge each summer evening to feed. Starved young could create a serious odor problem, not to mention needless cruelty.
Most bat species leave in winter, permitting exclusion in their absence.
However, some bats hibernate in buildings. When this is the case, or when one does not wish to wait for winter, there is a relatively simple exclusion technique that can be used after young are flying but prior to the winter months. It can be hung during daylight hours above areas where bats emerge, using duct tape or staples. Thus the netting acts as a simple one-way excluder until repairs can make the exclusion permanent. BCI does not condone the use of traps for removing bats from buildings.