How to Build Closet Doors for Sloping Ceilings

Measure the closet door opening, both up and down and side to side. Subtract 2 inches from both the height and width if the door opening is roughed in only. This means without door jambs, or the wood trim that faces the 2-by-4-inch boards forming the opening.

If door jambs are present or you plan to hang the door without jambs, deduct 1/4 inch from the door opening width and 5/8 inch from the height. This clearance allows for slight swelling of the door due to temperature and humidity as well as proper floor clearance.

Cut four pieces of 1-by-1-inch thick wood. Make two pieces measure the height of the door as calculated. Fit the other two pieces to the width, subtracting 1 1/2 inches each. These are the outside edge boards for the door.

Measure and cut two pieces of 1/4-inch-thick veneer plywood. Mark the wood in two or three spots for each dimension. Connect with a straight edge, drawing a line along the length to ensure accuracy. Use the exact door height and width as piece measurements.

Cut a block of 1-inch-thick wood measuring 6 to 8 inches wide and 12 inches in length. This will comprise the lock block, which is the wood plate on which the doorknob attaches.

Lay a sheet of veneer flat on your work surface. Outline the veneer edges with the outside edge boards. Fit the horizontal boards inside the ends of the vertical boards so all the boards meet at the butt edges. Measure from the outside edge of one corner to the outside edge of the opposite corner.

Create center support bracing for your door. Cut two additional 1-by-1-inch boards to fit the diagonal corner measurements.

Lay each center support brace in place on top of the veneer without the outside boards in place. Allow one brace to overlap the other and draw a line on either side of the junction. This indicates where to cut one of the braces to allow the other brace to pass through. Cut the section out, leaving two pieces in place of one diagonal board.

Set the outside boards in place again, flush with the veneer edge and resting on top of each support brace end. Run a pencil along the edge where the brace meets the outside pieces. Cut along these lines as well to allow the support brace to join the corner with the precise angle needed.

Squirt a bead of construction adhesive along the length of each outside board and place on top of the veneer in the proper position. Add the support braces, running diagonally, and the lock block, running along the edge where you want the door handle placed. Glue each piece in turn. Position the lock block, running from about 2 1/2 feet from the door bottom to 3 1/2 feet from the bottom.

Drive 3d nails or 1 1/4-inch-long finishing nails through each joint between the outside boards. Another nail driven through the outside boards into the diagonal braces and toenailed, or driven at an angle, through the diagonal support brace piece into the adjoining brace provides extra support.

Nail the lock block to the adjoining outside piece with four additional nails. These nails may be longer, since the block is wider than the other pieces.

Spread another layer of glue across each outside and brace piece as well as the lock block. Top the assembly with the last piece of veneer. Apply wood clamps to the door construction to ensure tight adhesion to the wood support inside. Set something heavy in the middle of the door as well to reinforce complete adhesion.

Remove the clamps and the heavy weight after 24 hours. Fasten the hinges to the door opening and attach to the door. Ensure the lock block is situated on the proper side of the door before hanging. Drill the door handle hole and latch hole as desired. Attach the door handle to complete.