More in Floors
To prevent a squeaky floor, be sure the subfloor is solid, especially if you have multiple subfloors. Nail it down until the pieces are secured and flat with no bounce. Try to nail it to the floor joists below.
Roll out the rosin paper. It acts as a moisture and sound barrier under a wood floor. Roll it the width of the room and overlap the pieces by at least 4". Secure it to the subfloor with a hammer tacker.
Make sure the new floor will run parallel to at least one wall -- ideally the squarest wall. Set up a laser line across the floor near the center of the room. Measure from the laser to the straight wall at both ends of the room. Line up the laser level across two tape measures to determine the straight line in the middle of the room. Mark two points along the line with a pencil.
Snap a chalk line along these marks. Spray a little hairspray along the line so it doesn't smudge.
Screw a batten board (a straight 1 x 2 board) into the floor along the chalk line about every two feet. This will act as a brace for the first course of flooring and prevents the flooring from shifting.