RH in Concrete for Wood Floor with Vapor Membrane

[Ernesto]

If this is a floating floor and not adhered then first off you should test the slab. If it close to 85% I would do a coat of Bostik MVP4, then a six mil plastic. Then float to your hearts content. Never had a failure with that even below grade using solid hardwood with a floating ply subfloor.

Heck even the new Bostik Single App says it will warranty a slab below 85% with no barrier under the slab.