Preassembled doors are designed for easy installation. If the door opening is outside the square, you can compensate by putting more wedges between the frame of the door trim and the wall opening. Perching doors are sold with the door and the frame, which makes installation easier for the homeowner. It is important to keep the square frame during installation so that the door continues to –Prehung Door function properly.
Insert prehung door the door in the opening prehung.Two wedges inserted in the spaces between the door frame and the inner face of the wall opening. Put in a wedge from the outside and the inside another so that the wedges are superimposed, so a bearing surface against the outer face of the door frame.
Continue prehung door placing two wedges spaced every 12 cm around the outside of the door frame. In places where the door frame misalignment causes spaces that are larger than two wedges, use many wedges as necessary to fill the space between the inner face of the wall opening and the outside of the door frame. Check that the door frame is level with a level of 4 feet at the top and vertically on each side. If part of the door frame is not square, a copy of the wedges on one side and tap them on the other side to reset the frame.