As a rule, the active panel is hinged to an inactive panel, with the latch at one of the side jambs, although three-panel units may have the active panel in the center. Swinging patio doors are available in wood, PVC vinyl, or in insulated steel or fiberglass. In general, a swinging door tends to be more secure and more energy efficient than a sliding door. At one time they were considered less secure than swinging patio doors because the active panels were locked to each other rather than a permanent jamb. With the advent of three-point locking systems that secure the door to the head jamb and the sill, French door security is much improved.
French doors are typically available only in wood.
2 - A swinging patio door. 5 - Shim directly behind the hinges on the hinge side. On the latch side, shim at the top, bottom, and both above and below the latch. 6 - The width of the gap at the top of the doors will tell you whether a French door pair is square or not. To install a prehung French or patio door, first unpack the new door unit.