We have moved into a house which used to have a flat concrete roof. This was changed to a pitched roof, and the whole loft space insulated with rock wool ie no joists. We are now in the process of moving all the shart from the garage into the loft. I believe I am right in saying if I lay boxes on the rock wool I compromise the insulation, will create a cold spot and have my own indoor water generator. So I was thinking about those plastic feet, wooden frame with interlocking loft boards to build a kind of free standing raft so the insulation isn't compromised. However if I bought kingspan sheets, cut them to fit through the loft hatch and then taped them together back into a raft. This would obviously squash the rock wool, but would the kingspan more than compensate for the compressed rock wool. PS I am skint so cannot do anything more elaborate. Any advise gladly taken.