Measure your mattress for width and height. Build the platform 2 inches shorter and narrower than your mattress so the mattress will "hang over" the platform edges by 1 inch on all four sides.
Calculate the dimensions of your platform bed frame parts. If you want a bed 18 inches from the floor, you'll want a frame that stands 12 inches tall; the mattress itself is approximately 6 inches thick, so 12 plus 6 equals 18 inches.
Measure the components of the platform frame onto sheets of ¾ inch thick plywood or medium density fiberboard (MDF). Measure two side panels that are the length of your bed and the height of your bed. Measure five end/middle panels that are the width of your bed---minus 1 3/4 inches---and the height of your bed.
Cut the frame parts out of the sheets using a circular saw. Move the parts to the open area on the floor where you will set up the bed.
Stand one of the side panels up on its edge. Match one of the shorter end panels at a right angle to the side panel at one end. Place the end panel on the inside of the side panel, not across the end of the side panel. Attach the end panel to the side panel on the inside corner of the joint using 1-inch angle irons. Use two angle irons per board, spaced 4 inches from either side of the middle of the boards. Place the angle iron against the two intersecting boards and drive screws through the holes provided in the angle iron. Attach the other end panel to the other end of the side panel in the same way. Attach the other side panel to these end panels. You should now have a rectangular-shaped box frame. The two end panels should be sandwiched inside the two side panels.
Insert the three middle support panels inside the frame, at an equal distance from each other and from the end panels. Attach these middle panels to the insides of the side panels using 1-inch angle irons. Use two angle irons per board, spaced 4 inches from either side of the middle of the boards. Place the angle iron against the two intersecting boards and drive screws through the holes provided in the angle iron.
Measure three top panels for the bed to make a platform lid in three sections. Divide the overall length of the bed by three. Each of your three top panels should be the length of the bed from side panel edge to side panel edge---and as wide as this three-part division. For example, a bed that is a total of 6 feet in length and 5 feet wide would need three top panels, each 2 feet long by 5 feet wide.
Place the first top panel across the top of the bed, from side to side of the platform frame. Use finishing nails to attach this top panel to the frame. Space the nails about 8 inches apart around the edge of the platform. Hammer the nails down through the top panel into the edge of the platform base. Lay the second top panel next to the first panel and nail it into place. Lay the third top panel at the foot of the platform and nail it into place. There should be no gaps between these top panels. Make sure the ends of all of the top panels are flush with the edge of the bed.
Add any trims or moldings desired to the fascias of the side and end panels.
Things You Will Need
- Measuring tape
- 3/4 inch thick plywood or MDF
- Circular saw
- 1-inch angle irons and screws
- Finishing nails
- Trims (optional)
- Stain or paint
- Paint or stain the frame to suit, including the top of the frame. MDF is particularly good looking when painted. You can also carpet your platform bed frame using carpet remnants or self-stick carpet tiles.
- Modify traditional bedspreads to work on a platform bed. Cut down and sew the bedspread so it just covers the bottom edge of the mattress, especially if the bedspread material is rather thick and difficult to tuck under the mattress. If you want a "tucked under" look, cut the bedspread down in size so you only have to tuck 2 inches of excess material under the mattress. It will make the "tucking" look less lumpy. Encase your mattress inside a mattress slipcover. Using a slipcover instead of a traditional fitted sheet will improve the appearance of the bed if you don't use a bedspread, or while the bed is unmade.