How to Make a Hollow Interior Door

Measure the doorway width, and subtract a quarter inch to account for movement and make the door fit. Measure the doorway height, and subtract a half inch for movement and floor clearance. Transfer these measurements to 2 1/4-inch plywood sheets, and cut them out using a saw. Sand the cut edges of the door using medium-grit sandpaper.

Cut out 1-by-1-inch boards to make a rectangular frame with the same dimensions as plywood boards. Set one of the plywood boards on top of the frame. Drill holes every 12 inches through the plywood board into the wood frame. Set 1-inch screws in each hole and tighten them down firmly to attach the plywood to the frame. Flip the plywood and frame over.

Cut out a 1-by-1-inch board to run within the frame vertically, centered in the middle of the frame. Set another 1/4-inch plywood board on top of the frame. Drill a hole every 12 inches through the plywood board and into the frame, including the central board. Set 1-inch screws in each hole and tighten them to complete the door frame.

Drill out a hole along one of the long sides of the door and through the largest door surface to make space for the door latch. Drill through the edge of the door into this other hole to make space for the section of the latch that sticks into the frame. Set the doorknob within the hole in the door and tighten it using the provided hardware. Thread the other component through the hole in the edge and into the main section of the doorknob to complete the door installation.