Engineered Hardwood Floor On Concrete Slab

Question:

Dear Doc,

A customer of mine would like a laminate floor put down over concrete, the problem is they saw another recent job I did in real hardwood and they want that look, I told them that it can’t be in laminate then, so I thought about an engineered wood floor system. I should back up a-bit to say the reason we don’t want to go full 3/4 hardwood is because by the time the sub floor goes down etc there will be a 2 inch step to the existing floor. So my question is can I put either 1/2 or 3/4 ply directly on the concrete (it’s a slab on grade not below, and 12 years old) and then nail an engineered floor to this? Also as far as stability goes could I instead of putting down poly back prime the plywood with a sealer so that I could glue the ply directly to the slab (after the ply has also been acclimatized)?

Answer:

Dear Dave

Read my article INSTALLING HARDWOOD FLOORS ON CONCRETE SLABS.