How to Build a Cat Door in a Shed

Making the Opening

• 1

  Locate the placement of the cat door. Decide if it will go through the main door or through one of the walls of the shed.

• 2

  Mark the opening for the cat door. Make the opening 10 ¾ inches wide and 13 ¾ inches high to accommodate an 8-inch by 11-inch door. The door is about the size of a sheet of paper, and the extra 2 3/4 inches added to the width and length of the opening are to allow enough room for the framing of the opening. Two of the inches are for the 1-inch framing on both sides with the 1-inch by 2-inch wood pieces, and the extra 3/4 inch is for the rubber that insulates the edges of the door.

• 3

  Draw level horizontal and vertical lines with a pencil and a level to outline the rectangular cut through the door or wall.

• 4

  Load the cutting blade into the handheld rotary tool. Turn it on and start the cut at one corner of the cat door outline through the shed door or wall. For wood sheds, use a standard bit and for aluminum sheds, use a metal bit. Cut along the pencil line until the opening is made.

Frame the Opening

• 5

  Measure the exact width and length of the opening with a tape measure.

• 6

  Cut the 1-inch by 2-inch pieces of wood for the opening. First cut the top and bottom horizontal pieces to 10 3/4-inches long, dry fit them into the opening, and then measure the distance between them for the two vertical pieces. This vertical distance should measure about 11 3/4 inches. Cut these two pieces from the 1-inch by 2-inch wood.

• 7

  Install the bottom and top pieces of the opening's frame. Apply wood glue along one 2-inch side of both horizontal pieces, and set the glued side down on the cut edges within the opening – one at the top and one at the bottom. Nail them into the existing wall or door with the pneumatic nail gun and brad nails.

• 8

  Install the two vertical sides of the door opening. Apply a bead of wood glue along one 2-inch-wide side and the two ends of each wood piece, and position the glued side flush against the sides of the opening, sandwiched between the top and bottom horizontal parts of the frame. Nail them into both the wall of the shed and into the top and bottom pieces of the frame. Allow the frame to dry.

Making the Cat Door

• 9

  Cut an 11-inch piece of the 1-inch by 8-inch wood for the door using the compound miter saw.

• 10

  Tack in the rubber strips along the 11-inch sides and 8-inch bottom of the door with a hammer and tacks. The rubber acts as insulation around the flapping door.

• 11

  Attach the hinges. Screw in two, evenly spaced, two-way hinges to the top of the door, which is one of the 8-inch sides. Align the hinges with the top of the door, and mark the pilot holes for the screws with a pencil. Drill pilot holes, and then screw the hinges to the door.

• 12

  Hang the cat door. Align the other side of the hinges, now attached to the door, to the top of the door opening. Mark the hinges' screw positions with a pencil. Drill pilot holes, and then screw the hinges to the top of the cat door.

• 13

  Paint or stain the cat door to match or coordinate seamlessly with the shed's appearance.