How to Install Baseboard Floor Trim
- 1). Measure the first wall from the corner outward, at the floor. Mark out the measurement on the back of a piece of baseboard. Don't measure from the end of the board, but rather set a starting mark in from the end of the board by about six inches, then measure off that mark to make a second mark. This is necessary because both ends of the board have to be mitered.
- 2). Set the baseboard on a miter saw, standing against the vertical guard rail that runs along the back of the saw's platform. Position the baseboard against the guard rail in the same way it will be positioned against the wall. Turn the blade to 45 degrees inward, toward the center of the span of baseboard. Cut it at the first mark.
- 3). Slide the baseboard so that the other mark is under the blade. Turn the blade to 45 degrees in the opposite direction as before, so it's again pointing toward the center of the trim. Cut it.
- 4). Repeat the process for the wall coming off the other side of the corner, measuring and cutting the trim to fit at both ends.
- 5). Set the two pieces of baseboard in place against the wall, with their 45-degree mitered ends meeting in the corner to form 90 degrees. Nail them to the wall with a finish nail gun, shooting the nails in along the top and bottom edges of each piece, every eight or 10 inches. Repeat the process for each piece of baseboard along each wall.
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