Crown molding finishes the joint between the wall and ceiling. Injection molding allows the creation of intricate designs at affordable prices. Polystyrene molding installs without nails. In order to install this molding you need a tape measure, a miter saw, sandpaper, a caulking gun, adhesive and the molding.
- Determine the amount
Use the tape measure to determine the perimeter of the room. Use this measurement to determine how much molding you need. Purchase 5 to 10 percent additional material for waste.
- Cut the molding
Use the miter saw to cut the angles. For standard corners, cut the end of each piece at 45 degrees. Use sand paper to ensure a tight fit. Some manufacturers provide materials with pre-cut corner angles, eliminating one of the most difficult steps in this process.
- Attach the molding
Use the caulking gun to apply the adhesive to the molding in a zigzag pattern. Affix the molding to the wall, ensuring there are no gaps. Hold each piece in place for approximately 1 minute to allow the adhesive to form a bond.
- Fill any gaps
Fill the gaps left from installation using painter's putty. After the putty is dry, sand to smooth the joints to give the installation a seamless appearance.
- Paint the crown molding
Manufacturers design polystyrene molding to accept paint or stain. Choose the appropriate finish for the newly installed molding, and apply according to the manufacturer's directions.