I will shortly be building my very own garage/home cinema. It will be built out of 6" thick concrete blocks, the building will be in an "L shape" and will be 6m by 3m, with the "L" part being 3m by 3m. The roof will slope from 3m to 2.5m. My hopes are that the cinema room will be 4.5m by 3m, as soon as the founds go in I will post pictures... For your info my Builder is building it and only charging £800!!!! I will be supplying all materials, which will cost £2000, that's including walls & ceiling. I was going to attach the walls to the floor & ceiling, will this be ok.