Installing Solid Wood Flooring on Concrete
- 1). Clean the concrete slab of any oil or grease spots using a cleaning agent that will cut through and take away any grime. Clean the slab either by hand, or use a pressure washer for stubborn dirt. Level high-spots using a grinder. Fill dips and valleys with additional concrete, and allow it to dry thoroughly.
- 2). Test the slab's moisture content. According to Woodweb, a simple way to do this is by placing a flat rubber mat on the concrete, weighting it down around the edges with bricks or heavy boards to seal it against the concrete. Wait 24 hours. If the concrete is darker beneath the mat, the moisture content is too high and must be allowed to dry.
- 3). Wait for the concrete to dry if moisture is present, which can take as long as 60 days. Otherwise, provide air circulation with large fans, and pull moisture out of the air with a dehumidifier. Add heat using a small space heater or by turning up the home's thermostat to speed up the process.
- 4). Apply a vapor barrier, such as polyethylene, asphalt felt or building paper. Place the vapor barrier of your choice on the concrete, overlapping the edges. With the latter two, trowel on a cold mastic and allow it to set before applying the barrier. Walk over the barrier after you finish to force out any air pockets beneath it.
- 5). Place 5/8-inch plywood on top of the vapor barrier. Use a power drill to secure the plywood to the concrete slab using long concrete screws, placing the screws at 16 inch intervals, according to The Family Handyman. Ensure that no gaps are present between the pieces of plywood. This layer is your sub-flooring.
- 6). Trowel urethane glue over the sub-flooring.
- 7). Lay down the wood flooring boards. Stagger them so that the ends of the boards are offset from one another by about 18 inches. As you place the boards, use blue painter's tape every foot or so to ensure they don't slip as you work. Keep the hardwood clean by wiping up any excess glue with cloths and mineral spirits.
- 8). Walk over the flooring once it is laid down, using your weight to remove any air pockets in the glue beneath the boards.
