Trevor that's a real predicament. My brother in Belfast had a colony relocated from his place by the RSPCA. They found a new home for them. Have you thought about building a bat house or two (or having them built for you) and attaching them to the eaves of your house the little critters might move house. You can find specs at the Bat conservation site. According to them the bats like tight spaces and they're houses are 3/4" deep, by 24" high and 16" wide. I just built a couple and hung them in the trees in our backyard, we're still waiting for inhabitants. On a positive note those little guys can eat 1000 mosquitos an hour. Apparently bat populations are on the decline world wide that's why pesky insect populations seem to be increasing.