During a recent remodeling job, I had to reproduce several arched tops in plastered openings to match one existing opening. Each opening was slightly different. The arches’ radii were tighter than any arch-forming product I could find, so I made my own arched corners. I was even able to integrate an arched top into a pocket door. Although I did my first arched pocket door trimmed with arched wood casing a few years ago, this one was almost all drywall.
The house was built in the 1920s. I thought I’d have to demolish and reframe a wall to install the pocket-door track, but I lucked out. I mounted the track to one side of an existing wall and covered it with a new wall that was blocked out 3-1/2 in. from the original. I made the corners for both sides of the arch, then bent a double layer of 1/4-in. drywall to the arch. The door had to be modified before I could hang it on the track, and I made sure I could access the trolley adjustments.
I cut plastic corner bead to conform to the arch, then taped and joined the entire doorway. I ripped and bent 3/32-in.-thick white-oak strips to act as stops on both sides of the door. After painting the jamb, I adjusted the door’s hang and cut the door for the recessed pull so that its position would match the other door hardware in the room.
Create an “archwich.”
To make the blocking for the arch, trace the pattern on 1/2-in. plywood, and rough-cut the curves on a bandsaw. The middle of the sandwich is an L-shaped frame of a vertical 3/4-in. ply and a horizontal 1/2-in. ply. Add an extra backing block in the middle that runs past the plywood curves and gets trimmed flush after the glue dries. The completed blocking is nailed in place.
Closely spaced scoring encourages drywall and bead to bend.
To make the drywall conform to the curve, score the back of each piece of 1/4-in. drywall on graduated intervals so that the scoring is about 1/4 in. apart. Moistening the drywall with water helps the process. Glue the strips to the blocking with construction adhesive, and tack with narrow-crown staples set at low pressure. Cut standard plastic corner bead at close intervals along the outer edge. Set the bead with spray adhesive, and add a few staples to keep it in place.