What To Put Between Mattress And Bed Frame. The lumber can be spaced with a 12” gap as the box spring frame is wood and reasonably strong. A bed frame should be no more than five inches bigger than a mattress in any direction.
It is one of the easiest and effective methods to keep the mattress from sliding on the bed frame. This may require two sheets of plywood if the bed is queen size or. Is enough to make you believe in monsters under the bed.