Bifold doors are now known under many different names

The earliest use of bifold doors is thought to date back to the Temple of Solomon around 953 BC; however they only really began to become popular in the 19th Century. Around this time, wardrobes or closets became commonly used in most households and bifold doors or folding doors became a choice available to those who wanted a different look to the average swing door.
Throughout the 20th Century bifold doors have varied in popularity as newer and more differing styles have become available. Although still often used for small spaces such as home offices, laundry spaces or closets, bifold doors or sliding doors are being used more and more on exterior applications, providing external sliding doors to open out onto outdoor spaces. There are many different styles of door available and a selection of materials to choose from including aluminium, wood and PVC, with many manufacturers offering bespoke designs.
The appeal of bifold doors, external sliding doors or folding doors lies in that they take up much less space than many traditional sliding doors or swing doors. They do not have to be centred into a supporting wall and they allow more options in terms of design, structure and build, allowing light into rooms and opening up a room where necessary.
Bifold doors are now known under many different names such as external sliding doors, and folding doors, as well as concertina and folding sliding doors. This particular variety of patio door came into existence in the 1980s. Early bifold doors were heavy, large, rather cumbersome and therefore difficult to operate due in part to their sheer weight and also insubstantial hardware. Common problems included early bifold doors becoming stuck on their running tracks and sometimes even coming off the tracks, or hinges altogether. When used for external purposes, old bifold doors would let in cold air, leak and cause a security risk. Because of this, in the past bifold doors were largely used internally to serve as room dividers.
Today, modern folding doors or bifold doors are by far easier to use and much more efficient than ever before. Due to advances in bifold technology, even the largest of doors are easy to operate. Sealed bearings, high security hinges and concealed running tracks all help to ensure ease of use as well as extra security and damage prevention. Newer designs also include improved fit and better seals, which allow increased protection from damage caused by the weather. Due to such improvements in both durability and security, bifold doors, folding doors or external sliding doors are now a suitable option when considering a patio door for external use, and in many cases it is even the safest and most aesthetically pleasing in terms of both design and function.