A soft mattress may lead to uncomfortable nights and a lack of restful sleep. A common signal of a soft mattress is back pain. A bed board improves firmness by providing solid support beneath the mattress.
According to SFGate Home Guides, you may purchase bed boards of various shapes and sizes or make them yourself. Typically, a bed board consists of thin plywood. To construct a bed board, measure and cut a sheet of 3/8 inch plywood to the size of your mattress. This may require two sheets depending on mattress size. Sand the board and edges to create a smooth surface and prevent any splintering. Wipe dust away, and place the board between the box spring and mattress.
Some foam and latex mattresses are designed for use without the need for a box spring. Use plywood bed boards for these mattresses as well. To construct a bed board for a mattress-only support system, remove the mattress from the frame, and measure the area upon which the mattress sits. Cut the plywood to size, and place on the frame. It may be necessary to drill holes through the plywood and frame, depending on the frame type. If slats support the mattress, place the plywood on top, or remove the slats entirely.