Every child dreams of having a secret movable wall panel. Creating a secret opening in a wall can add excitement and fun to your home. Secret wall panels can also add a measure of security for valuables, hiding them from thieves or taxing their efforts.
Find a location for your secret panel. The best location would be framed by wall corners, shelves, picture frames, baseboards and other things that conceal cracks or gaps around the edges of the secret panel. Look for an area that is 3 feet square in a non-load-bearing wall. (To make sure a wall is non-load-bearing, get the opinion of a licensed general contractor.)
Knock a small (head-sized) hole in a non-load-bearing wall where you intend to install the secret panel. Use the hole to look inside the wall for any pipes, wires, vents or other obstacles to your secret panel. If these obstacles exist, contact a general contractor before going on to the next step.
Measure and trace a 3-foot by 3-foot location around the hole in the wall. Cut through all studs in the wall at 90-degree angles with a saber saw. Keep the parts that come out of the hole as unbroken as possible so you can use them to trace the new parts. Save the baseboard from the sample you trim to re-use later.
Make a frame all the way around the inside of the 3-foot square hole. Using a miter saw, saw 3-foot 2-by-4 boards at 45-degree angles through the thin edge. A "flat" side of the each board should be facing the center of the doorway, with the larger of the two sides facing outward when you make the frame.
Screw the boards together at the corners from the outside of the frame. The screw should penetrate at a 45-degree angle through both boards using two 3-inch deck screws per corner. Do not let the screws cut across the interior of the frame. Frame the entire panel with one of the 2-by-4 boards going across the floor at the threshold.
Screw the frame to the studs so the screw enters the sides, not the end, of the 2-by-4, so the screw has a good grip.
Make another frame that fits inside the one you just installed into the wall. Since the one you installed was 3 feet square, make the new frame 33 inches long in each direction. Make the new frame the same way you made the other frame. If the new frame fits too tightly into the first frame, unscrew the second frame and shave a little off the end of the boards in the miter box.
Add center-hung pivot hinges with wood screws. Since the pivot hinges are meant to take the weight of the door, screw the hinges to the outer frame and inner frame (above and below) in the center of the secret doorway. Add two more 2-by-4 boards to the interior of the inner frame so they are evenly spaced one-third of the way from each side.
Close the door frame. Cut the drywall to fit the door frame on each side. Nail the drywall onto the face of the second frame using drywall nails. Shape the door frame so it fits up against the drywall around the hole. Carefully open the door to make sure that it works. You may cover the base of the outer frame using the baseboard trim you saved earlier or a section of drywall that you nail in place.
Turn on a fan and open the windows. Put a layer of cyanoacrylate glue into the exposed edge of the doorway and the drywall around the doorway to help prevent the drywall from crumbling. Allow the glue to dry in the open air. Paint the panel to match the rest of the room.