I was thinking of having cavity insulation fitted and kind of like the idea of the expanded polystirene beads. has any of you have any good or bad thing to say about it? My brother had a company came to his house but his wife said they were there for not more than a couple of hours, I had a quick look around but could only see a few holes that was drilled so I'm wondering if they did it properly but cant get any sense out of my brother. I search around on the web for information but the majority of infos are from companies that install these and the majority uses either blown fibre or that stuff that sounds like something an undertaker would use.