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Q   I enjoyed your magazine’s article about solid pine floors (Feb. ’02), but my house is built on a concrete slab. What can I do?

A   It’s considerably more difficult to install a 3/4-in. wood floor over concrete than over a wood subfloor. You’ll first have to install 3/4-in. thick wood underlayment.

The combination of the underlayment and flooring raises the height of the floor 1-1/2 in., so be sure the extra height doesn’t create problems around cabinets, in doorways or at transitions to other types of flooring.

Also, be absolutely sure that the concrete doesn’t get damp because of exterior water problems.

Lay 6-mil polyethylene sheeting over the concrete to minimize moisture migration from the concrete up into the wood flooring. Then fasten 3/4-in. treated plywood to the concrete with concrete screws spaced every 16 in. Alternatively, screwrows of treated 1x4s to the concrete 16 in. on center. Lay the 1x4s perpendicular to the direction you intend to install the floor planks.

Then nail the flooring planks with a standard flooring nailer (see photo for details).

TIP
If the 1-1/2 in. height change is too much, consider laying a laminated wood floor instead. It will add less than 3/4 in. of height. You can either glue it down or float it (the edges are either glued or snapped together).