I am about to start a single brick wall attached garage conversion into a kitchen extension. I propose to knock thru the gable end of the house, ( got a structural eng. presently sorting the calcs out for that.) What would be the quickest/easiest/cheapest way of lining the walls inside?. Would I be able to block up from the 100mm thick concrete garage floor, or would I have to dig thru the floor to the foundations? If stud walls, how would i construct these, given that I was told by a builder that they should have a cavity then DPM then blockboard then studs with insulation between and then pasterboard. If I put the studs up how do I fix DPM and blockboard behind if I have only 50mm cavity space between studs and brick outer wall? (did'nt think to ask the builder at the time) Confused!!