A bed frame designed for a queen-size mattress would not provide appropriate support for a smaller one because a queen-size mattress is typically 6 to 7 inches wider and 5 inches longer than a full-size mattress. The inconsistency could result in injury.
According to the Better Sleep Council, a conventional queen-size mattress is 60 inches wide by 80 inches long. A conventional full-size mattress, on the other hand, measures 53 inches wide by 75 inches long. A queen bed frame’s side rails would be unable to provide the necessary support to hold a full-sized mattress in place.
A full-sized mattress could only be supported by a queen bed frame with considerable cross support, such as one with a large number of wooden slats. However, gaps would still exist between the mattress and the bed’s side.