I am planning to install an engineered hardwood floor over a slab-on-grade subfloor. The slab is bone dry but I understand it's wise to install a moisture barrier anyway.
My plan right now is to cover the slab with 6 mil poly overlapped 12" and taped at the seams, then put some type of foam flooring underlayment over that, then install the boards as a floating floor.
Does this sound sane? Or is there a better/easier method?
If my approach is okay, does the 6 mil poly moisture barrier need to go a few inches up the wall, presumably hidden behind a baseboard? Or is it okay to have it end at the slab edge?
One thing I'm not clear about regarding the moisture barrier is how any moisture that finds its way under or over it is actually going to dissipate. Wouldn't it just stay there?