I am wanting to fit a full height conservatory, 3m x 3.5m, and need a base to build it on. It is not under building regs. I have looked at steel bases that bolt to the wall and stand on concrete footings, but they cost around Â£1100. If I were to build a concrete raft, as a base, what would the best depth be, and do I need to dig a trench around the perimeter, as I am not building a dwarf wall. I just need it obviously to be solid, with the minimum of work!!!
Any helpful tips appreciated