I am in the process of putting down my foundations and would like some advise on laying the slab. I am using 150mm of type 1, 50 mm sand, membrane then 100mm of concrete, 100 mm of insulation then around 60mm of screed. When laying the 100mm of concrete would you advise building the damp course bricks/blocks to a level of the proposed finish height of the 100 mm of concrete so I have a level to shutter off and then once that concrete has set I can carry on up to damp level or; lay 2 blocks and try for the best level finish I can but obviously will find it harder as there will be nothing to shutter off? any advise would be great .