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Patio door

Sliding glass doors, or as they are commonly called "patio doors", are used in a variety of installations opening from the interior of a residence or other room environment to a patio, balcony, or other exterior area. Sliding patio doors are generally constructed with light aluminum frames so that the door may be easily opened and closed without requiring substantial physical strength. Patio doors generally include a pair of panel members, usually made of glass, mounted in coplanar relation within a frame. One of the panels is usually supported for sliding movement relative to the other panel, within a track typically contained in or formed by the frame, so that the door panel can be slidably opened or closed relative to the fixed panel. Commonly, such doors have been provided with a simple lock mechanism which includes a finger which grasps a keeper on the door casing when locked by an operator inside the home. Wooden patio-door of conventional design normally comprises a wooden rectangular frame in which are mounted panels having a wooden structure and carrying a suitable glazing unit, either a single glass pane or a sealed double or triple glazing unit. Such patio-doors are generally made of relatively soft wood such as pine or cedar, which implies large tooling-tolerances. Patio doors have found widespread acceptance in houses and apartments, due to the ease of opening a relatively large area and the amount of daylight illumination provided by such doors.

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