Planning to Refloor a Basement
Tom Silva discusses the wisdom of covering an engineered wood floor
We have an engineered wood floor glued to the concrete in our basement. Can I go over it with tile or another layer of wood, or will the glued flooring have to be removed? —Bonnie Varnes, via e-mail
It depends. You can go right over the engineered flooring with another layer of wood flooring, assuming the original layer is flat and well adhered. But if you choose tile, then the old floor will have to go. Wood buried under a layer of concrete and mortar provides a perfect environment for rot.
If you’re going with wood, you can either nail down strips or planks in the traditional manner or float an engineered flooring over the original. For a nail-down application, first secure 3/8-inch plywood underlayment to the old flooring using construction adhesive and staples, then nail the new floor to the underlayment. With a floating floor, there’s no need for that extra layer of plywood; a thin foam mat serves the purpose.
For a tile job, once the old floor is gone, lay sheets of cement backer board in thinset and cover the joints with fiberglass tape. Then tile as usual.