Abstract: A stair frame may be used to form a straight staircase, a spiral staircase, or a combination of the two. The stair frame includes an elongated angle having a leg and a back, the back cut into a plurality of independent back portions and the leg bent into a zigzag shape with alternating vertical and horizontal leg portions. A rail is fastened to the upper end of each vertical portion back and the forward end of each horizontal portion back to secure the angle into a sturdy frame which may be bent into a helical pattern. The horizontal leg portions serve the dual purpose of forming sturdy frame, and supporting one end of the staircase treads.