A secret door is a great way to stash your less-than-pristine rooms from the gaze of your guests and add an element of mystery to your home. Camouflage a door behind a bookshelf to create storage and blend seamlessly into your common area. Whether it's to protect your personal family secret or just get your messy laundry room out of sight, enjoy extra privacy by adding a hidden door to a room you would rather see less of.
Remove the door you plan to camouflage from its hinges and remove the hinge hardware from the door. Install heavy-duty hinges on your door according to the manufacturer's instructions, so that the door swings out into the room you intend to hide. The heavy-duty hinges are necessary to hold up the weight of the camouflage for the door. Use the existing holes from the old hinges to fit the new ones, if possible, or drill new holes for the screws and attach the hinges.
Remove the doorknob and install a touch latch, which allows you to push the door slightly to disengage the latch and open the door. Depending on manufacturer instructions, you will either need to screw the latch pieces into place or peel off an adhesive strip and attach the latch to the inside of the door and frame.
Cut the plywood into straight pieces of equal width by dividing it into six pieces lengthwise. Cut two pieces that are long enough to fit across the door horizontally from those pieces. These will be the top and bottom of your shelf.
Cut two of the long pieces of plywood to fit vertically over the door. These are the sides of the bookcase.
Glue the edges of the sides to the top and bottom and secure with wood screws.
Cut three or four shelves from the long pieces of plywood that are 1 1/2 inches less than the door's width so that they fit snugly into the outer shelf unit.
Slide the shelves into position, level and nail into place from the outside.
Cut the cardboard or thin wood sheeting to size to fit over the back of the shelf without overlapping. Secure the backer board to the back of the shelf with nails.
Secure two of the 2-by-4 wood pieces to the door with wood screws vertically. Cut three pieces from the third 2-by-4 that are long enough to sit horizontally between the two pieces of wood and secure with wood screws. Make sure to screw the wood so that it lays wide, only extending 2inches from the door.
Toenail or screw the shelving unit to the 2-by-4s at an angle to secure the hard plywood pieces to the door. Remove any molding around the door. Sand all surfaces and paint your desired color.