The outbuilding I am converting to a shop has a concrete slab. I plan on putting down hardwood on half of the building. Instead of using sleepers I want to attach the subfloor directly to the concrete. The concrete remains dry but we do have a high water table. The manufacturer recommends 6 mil poly glued to the concrete with the AdvanTech then attached using fasteners driven into the concrete. I am reluctant to do that for fear I will be opening channels for water to come up through the concrete. Could I not skip the poly and use waterproof adhesive to attach the AdvanTech directly to the concrete?