How to Frame an Archway

Determine the width and height of your arched doorway. Interior doorways typically should be at least 36 inches wide. Mark the width measurement on the bottom and top wall frame plate where your door will be located.

Cut a section 4 inches wider than the doorway from the bottom wall plate with a circular saw. Remove the plate sections and any studs connecting these sections.

Measure the distance between the floor and the ceiling on both sides of the doorway. Cut two sections of 2-by-4-inch lumber 2 inches shorter than this measurement with a circular saw. These sections will form the studs of the doorway.

Stand one of the studs at each side of the doorway against the cut end of the bottom plate. Check the studs with a carpenter's level to ensure that they are vertical. Drill two pilot holes through the studs into the cut ends of the bottom plate with a drill, and secure the studs to the bottom place with 4-inch wood screws and a screwdriver.

Drill pilot holes through the studs into the top plate at 45-degree angles. Insert and tighten 4-inch wood screws to secure the studs to the top plate.

Measure and cut two sections of 5/8-inch plywood according to the interior width of the door frame, and according to the distance between the ceiling and the point where the arch meets the door studs, using a table saw.

Draw the curvature of the arch on one of the plywood sections. Stack the plywood sections, clamp them together and cut out the arch with a jigsaw.

Place one of the plywood sections so that the top and sides are even with one edge of the ceiling plate and the door studs. Drill pilot holes through the wall studs into the ends of the plywood at 4-inch intervals and secure the plywood with 4-inch wood screws. Repeat this process with the second plywood section on the opposite side of the wall.