In that case a line across the top centre, right the length of the loft. Even down and around. Never seen - or heard a pigeon getting a shock. Some have the wire just so the cat can crawl in under.... But they have their tail up like a mast. They don't scatter fast enough, and alway rember. Two, three strands like a fence. No matter for the wire can be as long as you like. Never mind him seeing it, it is legal. And if anyone get a jolt from it, then they should be up there. However thay'd be insulated for they would be up to no good. Never had a nieghbour complain yet ... mind very few , if any, know mine is there. Least said, known the better.