Sliding patio doors, also known as gliding doors and sliding glass doors, are found in virtually every home. They have a similar appearance but operate differently than a French door which swings in or outward. The operating glass panel of a sliding patio door glides on rollers on a track in the sill. This design provides great ventilation with the operating panel stored completely and safely out of the way when in the open position.
A French door, which is also sometimes referred to as a French window, is a door made up of panes or panels of glass with frames or partitions separating each pane. Glass panes are generally rectangular in shape and make up the majority of the doors surface.
The French door is typically sought after to bring an element of style and offer more natural light into a home. It is also used as a way to divide rooms and set them apart while still maintaining an open feel to the overall space.
In the past, wood entry doors were susceptible to warping when exposed to extremes in the weather. The door, which would be perfectly aligned in the summer, would suddenly become hard to open or close when the weather turned cold. Once the homeowner adjusted the door, summer weather would return, and the humidity would cause the door to stick and need readjustment.