What is a bi-fold door?
A bi-fold door consists of two panels attached by hinges, which folds in the middle when opened. The easiest way to imagine it is as a basic, standard hinged door, albeit with an extra set of hinges in the middle of it. Often, the top corner of the outermost door panel is attached to a rail running across the upper part of the door frame, so that it simply 'slides' along the width of the doorway.
The bi-fold door design requires much less space to operate than a hinged door does, as it will only take up half as much room when it's fully ajar, and has a much smaller swing arc. These doors are often used where space is at a premium, but they can also make for an interesting feature in their own right.
Bi-fold doors are most commonly made of wood, but can also be made of metal or glass. Other names for bi-fold doors include concertina doors, convertible doors, accordion doors, folding sliders, and multi-folding doors (among others).
How does a bi-fold door work?
In most cases, a small, recessed handle or pull is installed in the middle of the door, allowing it to be easily opened from the middle hinge. Pulling or pushing the door bends the hinges in the middle of the door, folding the door in the middle. The door is then opened up the rest of the way.
In most cases, if a bi-fold door has a locking mechanism it involves a latch at the top or the bottom of the door near the central hinges, often in tandem with another at the door jamb where the door opens. Larger bi-fold doors may also serve as a regular hinged door when these middle latches are locked.
Where are bi-fold doors used?
These doors are commonly found as wardrobe doors, and are often louvered to allow ventilation so that the clothes kept behind them can breathe. They save on opening space, which can be seriously precious in smaller bedrooms - especially in apartments. They can also be used as room dividers to convert two smaller rooms into one large one, as doors to conceal a pantry or small laundry, or as general interior doors in any home with a limited amount of space.
Another way that (larger) bi-fold doors can be used is as a glass wall onto a panoramic view or a back yard setting, which can be opened up in good weather. These doors are fantastic for throwing open to lead out onto a decking or back garden when you’re entertaining, and will still allow a great view when closed. Stacker doors can also be used for this purpose.
What variations exist in bi-fold doors?
The variations are limited only by their application and material. Bi-fold doors can be used for anything from small particleboard kitchen cupboards all the way up to oversized, double glazed wooden framed bi-folds that double as panoramic windows - sometimes with many more than just two doors. As mentioned earlier, stacker doors can be used for similar purposes, and in some configurations bi-fold doors can be detached from each other to allow for more options in terms of how they're controlled.