in
Haus Wittgenstein, Vienna (1927) Locking or latching mechanisms have existed from about the same time. Key operated door locks have existed at least since Egyptian civilisation. The keys of these locks, which could be as large as two feet long, also functioned as door handles to slide a locking bolt and open the door. Subsequently
Roman domuses and
insulae incorporated lockable doors of a different design but also opened by a combined handle/key. Although available, these key lockable doors were relatively rare. Houses were almost always occupied so most lockable doors would feature a sliding bolt or a drop-in bar that allowed the building to be locked from the inside. The bolt or bar bracket acted as a handle. Although interior doors were less common in Rome than in modern buildings, the Romans had recognisably modern interior doors including door handles. Doors excavated from Lake Nemi and dated to around 1st century CE feature knob-shaped handles. In Asia, China by the 4th century CE was producing a range of automated doors, door locks and door bars. There is little record of door handle development between the
Fall of Rome and about 1000 CE. The oldest European doors include the
Bernward Doors and the
Westminster Abbey door. The Bernward doors have large decorative ring-shaped handles of a type that became common on decorated doors from that period onwards. The Westminster Abbey door features a sliding bolt that can also function as a handle. From at least the
Middle Ages blacksmiths made drop latches which could be opened by a handle connected to the latch by a split pin passing through the door. Taking the form of a ring or strip, these handles could be elaborate and decorated but were universally made of metal. It can be speculated that since the task of making door hardware fell to the blacksmith, the use of turned or carved wooden knobs was not convenient. Wooden latches are also known from this period. A finger hole could be made that allowed the user to raise the latch from the other side of the door. The finger hole would double as a grip or handle. In another common design, transferred motion to open the latch was effected by a string passing through the door, which could be withdrawn from the inside to effectively lock the door to outsiders. In this case the door might also have a basic handle carved or turned from wood. Vertical handles with an incorporated latch mechanism, known as
Suffolk latches were developed. By the mid-18th century, forged vertical handles were being replaced by cast vertical handles, including the
Norfolk latch. by Jean-Ernest-Auguste Getting () The early 17th century also saw metalworking of a standard that allowed
mortise locks and latches and compact
rim locks and latches to be made for use in the most expensive buildings. These locks used a twisting motion to operate, accelerating development in decorative doorknobs. The
Industrial Revolution dramatically reduced the cost of lock and latch manufacture with lock designers including
Barronin,
Chubb and
Bramah competing against each other around the end of the 18th century. From the 18th century, a wide variety of lever handles and knobs started to be produced, with designs determined by local aesthetic preference and technology. Knobs could be cast, turned, brazed or spun from a variety of materials. Levers could be wrought or cast. Designs became more complicated and might include a rose or escutcheon plate. Until about 1830 door handle manufacture in the western world was almost entirely European. In 1838 the US was importing between 80 and 95% of its door handles. Between 1830 and 1876, the date of the
Centennial Exposition, door handle manufacture grew rapidly in the US; more than 100 patents were filed for door handle and doorknob improvements in that time. From the early 20th century architects and designers started to take serious interest in door handles as part of a comprehensive vision of spaces for living.
Peter Behrens,
Walter Gropius and
Antoni Gaudi all produced handle designs, many of which continue to be manufactured. While aesthetic design, cost of manufacture and functionality remain primary drivers of door handle design, the 21st century has seen additional considerations introduced. In particular, considerations of infection control {see section below} and
accessibility have become increasingly important since around 2000. The Coronavirus pandemic has contributed to a rapid development of new handle designs including foot-operated handles and handles that can be operated by the user's forearm. == Escutcheon plate ==