Forgive me but I don't understand how these are allowed - don't people have trouble with insurance? We used to live in a flat where the loft was connected to the neighbours on either side. Also we had a connecting door in the actual flat to the people next door, shock of my life when we opened it the first day we moved in and we're straight into next doors living room!it worked out ok though, we were young and they were too, and we used to have massive parties across both flats! Thinking about it now though, I wouldn't like it for security reasons!