Professionals refer to the rectangular frame of loft ladders, which is installed in the ceiling and in which the staircase remains when folded in, as a hatch box. The length and width of the hatch box must match the dimensions of the ceiling opening. In addition, when buying an attic staircase, you should choose the height of the hatch box according to the measured ceiling thickness. Hatch boxes can be made of wood or MDF. For many hatch boxes, Minka also offers a matching top cover that increases thermal insulation.