It is hard to believe that the mechanism used in lavish sliding entrances to patios, verandas and pool houses or the glass variety known as Arcadia doors used in upmarket office buildings is the same mechanism used commonly in bedroom wardrobes or armoires, even modest ones. Aesthetically pleasing as they are, wardrobe sliding doors appeal as much for their economy of space. Since they open sideways just like accordion doors used in the garage, there is no need to allot space as you would for a traditional door that swings forward or back.
The most common kinds of the wardrobe sliding doors are Pocket and Bypass. Pocket doors have movable panels that disappear into a compartment – a pocket – in the adjacent wall. Bypass doors have panels that move to either side so that they can overlap – or bypass – each other from the front or behind. In some instances, only one panel slides while the other is fixed. The panels are typically supported by a roller system held in place by concealed carrier tracks, which may be top-hung or bottom-hung.
Top-hung carrier tracks do not require matching floor tracks as they can sustain the weight of the panels on their own. On the downside, there is merely so much weight they can carry. Bottom-hung carrier tracks need the help of matching overhead tracks to stay aligned despite the gravitational pull. On the upside, they can carry as much weight as the ground can. They go on sale at similarly cheap prices in a choice of aluminum, PVC or stainless steel, the strongest choice. Corrosion-resistant and self-lubricating, the same materials are used for panel frames and door hardware like bearings and hinges.
Space efficiency is evidently valued in closet doors, which is why another common type is bi fold doors, in which the panels comprising each unit are gathered to the side in pairs just like folding doors are parked where the tracks end to create multi-purpose spaces. As for wardrobe sliding doors, panels are affixed to a roller system, which is what runs along the carrier tracks. Many shower, laundry, utility and study rooms also make use of sliding entryways.