Who was Murphy and why did she need a bed that folded up into the wall? I don’t know who Murphy was but I have a pretty good guess as to why she needed the folding wall bed. She probably lived in a very small room and the bed took up too much of the room space. So a bed that folded into the wall seemed like a great solution to free up more floor space. Thus you have the Murphy Wall Bed. Do you need space too? Then let’s get to work.
First select which wall you will use for the bed. Next select the size of bed you want. Most Murphy Beds are singles as the room is small and when the bed is down you do not want it taking up too much space. A full, queen or king bed may fill the room when pulled down. We will assume you are using a single bed.
Measure the width, length and depth of the mattress. These measurements are the ones you will use to create a box, drawer, in which the mattress will rest. Remember this box will show when the bed is in the wall so select a good looking wood. Nowadays veneer plywood is easy to find and fairly inexpensive. Of course you can always paint the wood a particular color. The box should hold the mattress snugly and the side boards should rise nearly, but not quite to the edge height of the mattress.
Secure the corners and edges of the box with substantial fasteners. The bed box will take a lot of stress in its movement so it should be well connected. Use some metal fasteners or substantial wood screws. Nails are not the best choice here. If using screws make certain they are countersunk into the wood so no jagged screw heads are sticking out of the wood. Screws not countersunk into the wood can cause harm and make it difficult for the bed to fold into the wall.
Your mattress now fits snugly and securely into the bed box. Now you have to figure out what size wall hole you need into which the bed can fold. Take your bed box, place it on the floor, slide the head of the box tightly up against the wall where you plan to store the bed. Then transfer the width of the bed box to the wall by using a straight from the side of the box and drawing a line vertically on the wall. Do this on both sides of the bed. Now you have the width of the hole needed on the wall.
Next measure the length of the bed box. Take this measurement and transfer it onto the lines you have drawn on the wall; measuring from the floor up. This now gives you the height of the hole needed.
Before you cut the hole there are some items to consider. First make certain there are now electrical wires, plumbing or gas lines behind the wall. Severing any of these items can be messy if not dangerous. Once you have ascertained this start cutting the hole in the wall. If the wall is drywall material a simple drywall saw will do the job. If the wall is the old lathe plaster this will be messy. Put down a drop cloth, use a saw to outline the edge of the hole making sure you have cut through the wood lathe. Then start ripping down the lathe plaster.
If at all possible you should have planned your wall hole placement so that one side of the hole is a 2×4 wall stud. This will make the bed more secure to the wall’s frame structure. If you did do this all you need to do is add another 2×4 stud to the other side of the hole. Make certain the stud is plumb. Use a level. Then across the top of the hole use another 2×4 as a header. You should now have a rectangular 2×4 frame on your wall. Make this frame about a half an inch to an inch wider than your bed box. This ensures the bed box will fit in the frame. Any gap on the side can be hidden by adding molding at the finish stage.
Now you need a box in your wall hole for the bed box to sit when it is folded into the wall. Again this should be good looking wood as it will be seen when the bed is pulled down. If you did your wall frame correctly it should be slightly larger than your bed box.
So all you need to do now is build another box that fits into the hole at the width and length of the wall frame and as deep as the bed box frame plus the height of the mattress sticking up over the mattress. Once this box is built slide it into the hole and connect it to the two by four frames. For even better security, before you place the box in the hole, securely add some 2x4s to the back of the hole. Then, once the box is placed in the hole you can secure the box not only to the 2×4 frame but also through the bed of the box into these rear 2x4s.
How are we going to get the bed to swing up into the hole? This is where the magic of piano hinges arrives. Piano hinges cover the length of your item. So in this case we apply one side of the piano hinge to the bottom of the mattress’s box headboard. The other side of the hinge is attached to the floor at the bottom of the good hole. Attach the other side of the hinge to the bottom edge of the wall box.
The bed is now ready to fold into the wall. But how will you keep it securely in the wall when it is not being used? There are lots of possibilities here. The simplest option is to add an eye ring to the wall and a hook to the bed box. Do this on either side of the bed box. When the bed is folded into the wall simply hook the hooks on the bed box into the eye rings on the wall. Pick an appropriate size hook and eye that can hold the weight of the bed box.
Now it is time for the wall finish work. The edges of the hole wall are probably pretty ragged from the sawing. If it is drywall you may apply a metal corner edge to the drywall and plaster over the metal edge making a smooth transition with the wall. This takes some time as you should do a thin coat and sand; repeating this three or four times until the plaster is level with the wall plaster.
Or you can buy some wood trim moulding and cover the edge of the ragged drywall with the molding. Simply cut the moulding to the lengths you need, miter cit the corners and nail into place. This same tactic works well for lathe plaster. Lather plaster should only be done by a professional. It is hard to do, but it is also a dying art and lathe plasterers can be hard to find. Use moulding.
Now after all this hard work, pull the bed down and take a nap.