- 1). Remove the trim around the room, using a hammer and pry bar. Remove it without breaking it. Set it aside. Get the floor clean and dry.
- 2). Pour floor leveling compound over all cracks, holes and low spots on the concrete floor. Even out the compound with your cement trowel. It doesn't have to be perfectly level everywhere, just flat and relatively even. Let it dry for 24 hours.
- 3). Roll foam underlayment out along the longest wall in the room, right on the concrete floor. Cut it at the end to fit against the side wall, using your utility knife. Roll out next course next to the first one, and tape the edges together with one long strip of tape. Repeat for each course, until the whole concrete floor is covered.
- 4). Set your first boards alongside the wall with the grooved sides facing the wall and the ends fitted together. Place wood shims between the grooved edges of the boards and the wall, to make a small space--this will allow the floorboards to expand with environmental changes. Cut the pieces at the ends to fit against the side walls.
- 5). Lay the rest of the courses of planks in the same manner as the first, connecting them by the tongue-and-groove sides and cutting them as needed at the ends with your miter saw. Cover the whole room.
- 6). Cut the last course of boards lengthwise with your table saw so they'll fit against the far wall. Leave the width of a shim by the wall.
- 7). Remove all the shims. Put your floor trim back in, covering the spaces and holding down the boards.
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