How to Create an Archway
- 1). Remove any drywall or wooden door jamb that is still remaining on the inside of the door opening. Any wood, drywall or corner bead can be removed with a flat pry bar and hammer. Work gloves and a dust mask should be worn during any dismantling activity.
- 2). Measure the width of the door opening and cut two square pieces of plywood using the width of the door opening as the size of the square. Use the sawhorses to set up the plywood and cut the material with the circular saw. Always wear goggles, ear plugs and a dust mask when using a circular saw.
- 3). Mark the center point along the bottom of the plywood. If your sheet is 34 inches wide the center point will be at 17 inches.
- 4). Extend a vertical center line from the center point with a framing square. Mark a point on this line 10 inches up from the beginning of the vertical line.
- 5). Drive a nail through the mark and attach a string to the nail. At the other end of the string tie a pencil so the pencil reaches the outside edge of the plywood, when pulled tight. Now scribe a semicircle with the pencil on the plywood.
- 6). Cut out the curve of the plywood with a scroll saw. Always wear safety goggles and dust mask when cutting with a power scroll saw.
- 7). Cut a second piece of plywood identical to the first.
- 8). Cut 2-by-4 blocks to place between the two sheets of plywood. Length of block will vary with size of the wall. New 2-by-4 walls will require 2 3/4-inch blocks, while new 2-by-6 walls will need 4 3/4-inch blocks.
- 9). Nail the outside edges (top and side) of the plywood pieces together with the framing blocks and #6 rosin coated nails. Leave out the blocking from the arch area for the time being.
- 10
Adhere the arch to the door frame with caulk gun, construction adhesive and a few #8 rosin coated nails driven through predrilled holes in the wooden blocks. - 11
Attach 2-by-4 blocks to the bottom curve of the arch using drywall nails or screws to penetrate the plywood and attach into the wooden blocks. - 12
Measure the distance along the face of the curved arch. Cut a piece of 1/4-inch Masonite to this length. Width should correspond with the thickness of the wall. (3 1/2 or 5 1/2 inches in most new homes) - 13
Screw the Masonite into the bottom of the arch using 3/4-inch screws. The Masonite should have enough flexibility to make the curve. - 14
Cut a sheet of 3/8-inch drywall with a utility knife. Make the drywall the same size as the Masonite. Cut the drywall piece from the center of the sheet so there are no tapered joints on either edge. - 15
Turn the Sheetrock over and score the backside of the paper with knife cuts about 1/8 to 3/16-inch deep. Place each cut about an inch apart. These incisions will make the drywall flexible, so it can be attached to the Masonite. - 16
Attach the drywall to the Masonite with 1-inch drywall screws. Be sure to sink the head of the nail past the face of the drywall without breaking through the paper. - 17
Cut two side pieces of drywall to cover the plywood. Each piece should have a curved arch that matches the plywood and extends down to the edge of underneath drywall. - 18
Install corner bead along each edge of the arch. One flange of the bead gets notched every two inches with tin ships, while the other side remains uncut. The uncut side goes on the under side of the arch. Attach the metal corner bead carefully with drywall screws. - 19
Plaster and paint.
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