Dont get me wrong, I love them, only when they are outside. I found one dead bat inside the furnace on the floor and we are totally stumped how it got into the furnance. Our chimney is about a good two foot away in exhaust pipe. The furnance is in the basement. We have two main floor cold air intake and all the heat/cooling comes from our vents on the main floor. The chimney has a cover and mesh so how in the world did this bat come inside of the furnance???????????? One time a few years ago, we had a flying bat coming in from the basement into the main floor that we caught and let loose outside. We checked under the eaves, under dormers, anything small of a crack that can be accessed to a rat we found nothing. Dont tell me we got bats in the chimney!!! (I know, we looked and there was nothing down there).