How to Hang Crown Moulding
- 1). Place the molding into place along the seam between the ceiling and the top of the wall. The edges of modern crown molding are beveled to fit flush against the ceiling and wall, leaving a small cavity behind the molding that is not seen. Note the cut required for each end of the molding; each cut could be a scarf joint, interior corner joint, or an exterior corner joint. Mark the location of each cut on the molding with a pencil.
- 2). Create a scarf joint when the piece of molding is not long enough to cover the entire length of the wall. For this cut, place the top of the crown molding piece against the bed of a compound miter saw and the bottom of the molding piece against the fence of the saw. The crown molding should be positioned just like it is positioned against a wall, only upside down. Cut one edge of the molding while the saw is at a 45-degree angle. Cut the other edge of the molding in the exact same position, only keeping the length of the molding on the opposite end of the saw blade to create a sister cut.
- 3). Create an exterior corner joint when the piece of molding must extend to cover an exterior corner. Place the molding in the same position used to create a scarf joint. Cut the first edge of the molding with the blade set at 45 degrees to the right of center. Cut adjoining piece of molding with the blade set at 45 degrees to the left of center.
- 4). Create an interior corner joint when the end of the crown molding butts against an interior corner. For one edge of the cut, simply cut the edge of the crown molding to the appropriate length so it ends at the corner of the wall. For the other edge of the cut, use a coping saw, angled to remove the back of the crown molding, to cut along the entire decorative edge of the molding. The thin blade of the coping saw will remove the thickness behind the surface of the molding, creating a edge that will fit against the face of the decorative molding. Use medium grit sandpaper to smooth any rough areas.
- 5). Install the piece of crown molding after both edges have been cut using finishing nails and a hammer on the top and bottom of the crown molding. Be sure to avoid hammering into the cavity behind the wall; make sure you hit a stud or joist with every nail. Use a stud finder as necessary to locate structural members to nail. Use a nail set to depress the head of each nail and avoid marring the crown molding.
- 6). Hammer a pair of nails into the wood over every scarf joint for extra reinforcement. The nails at both the top and bottom of the joint should go through both pieces of wood. Use a nail set to further depress the nail heads.
- 7). Continue installing pieces of crown molding using the techniques above until all of the molding is installed. Fill the holes created by the nail heads with wood putty and a putty knife. Allow the wood putty to dry completely, then sand away any imperfections with a fine grit sandpaper.
- 8). Stain or paint the crown molding using a paintbrush. If the molding was purchased already painted, touch up the areas that were cut or fixed with wood putty. Use painter's tape to isolate the crown molding and to avoid accidentally staining the wall or ceiling if both have already been painted.
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