Prefab slab on grade / Discussions

...on. I've been looking at the Legalett raft slab on grade kits but I don't think they provide advice on grading. Any advice would be appreciated - and also where to find a good engineer - there seem to be a lot of cowboy contractors out there!  A raft slab is different than standard slab on grade construction, and it pr...

...Ontario (Zone 6A). We want heated slab on grade but are concerned about preventing seasonal issues in winter. Legalett systems look very good especially their air radiant system. The question for us is what happens in winter when we are away for a few weeks? We'd need to keep heat on? At what level? Would pipe size in ...