How to Put Molding Around Doorways

Measure 1/8 inch from the edge of the doorjambs with a tape measure and draw an outline of the doorway along the full length of all three jambs. You will install the molding along this line. Also known as the reveal, this 1/8-inch space allows for door movements.

Cut one end of a scrap piece of molding so it has a 45-degree angle. Do the same with another scrap piece. Using a miter saw to cut angles makes your job easier, but you can also use a compass to measure the angles and cut them with a handsaw.

Hold the scrap pieces with the angled portions on top and the longer sides away from the door. Position them as if they were the upper ends of the leg moldings, on either side of the door along the lines you drew in Step 1. Hammer some nails through the molding into the wall to temporarily keep them in place. These scrap pieces help you measure the appropriate lengths and angles of the molding.

Measure the distance between the highest points of the two pieces of scrap moldings. This gives you the length of the head molding.

Cut a piece of molding the appropriate length for the head molding. Cut off a 45-degree angle at both ends of the piece to make them fit the leg moldings.

Hold the head molding in place, along the line you drew in Step 1 and between the two scrap pieces of molding. Hammer nails through the head molding to keep it in place. Use 3d or 4d nails for the bottom of the molding and 6d or 8d nails for the top of the molding. Keep the nails at least 1/4 inch from the edge of the molding and 1 inch from the ends.

Remove the scraps.

Measure the distance from the top of the head molding to the floor.

Cut two leg pieces the length you measured in Step 8, each with one 45-degree end that will fit the head molding.

Hold the leg moldings in place and hammer nails through them as you did with the head molding.