Product Code Database
A door handle or doorknob is a handle used to open or close a door. Door handles can be found on all types of doors including: exterior doors of residential and commercial buildings, internal doors, cupboard doors and vehicle doors. There are many designs of door handle, depending on the appropriate use. A large number of handles, particularly for commercial and residential doors, incorporate latching or locking mechanisms or are manufactured to fit to standardised door locking or latching mechanisms.
The most common types of door handle are the lever handle and the doorknob. Door handles can be made out of a plethora of materials. Examples include brass, porcelain, cut glass, wood, and bronze. Door handles have been in existence for at least 5000 years, and its design has evolved since, with more advanced mechanism, types, and designs made.
Some door handles are also arm- or foot-operated to reduce transmission of contagious illnesses.
In Asia, China by the 4th century CE was producing a range of automated doors, door locks and door bars.John Needham: Science and Civilisation in China
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common design, transferred motion to open the latch was effected by a string passing through the door, which could be withdrawn from the inside to effectively lock the door to outsiders. A book on Canadian history describes how "The term 'latch string out' held great meaning to any pioneer woman. If a cabin door’s interior latch had a string on the outside, anyone could open it." See Eleonor G. Luxton, Latch String Out, Summerthought Publishing, Banff, 2015. In this case the door might also have a basic handle carved or turned from wood.
From about mid-17th century, drop handles were increasingly replaced by forged vertical handles formed as a bracket fixed to the door at the top and bottom of the bracket. Vertical handles with an incorporated latch mechanism, known as were developed. By the mid-18th century, forged vertical handles were being replaced by cast vertical handles, including the Norfolk latch.
The early 17th century also saw metalworking of a standard that allowed and latches and compact 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 Locks 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. This period also saw glass doorknobs appear as a major part of the industry thanks to improvements in the pressed glass manufacturing process. Cut glass knobs were also popular from the time of the Centennial Exposition to about 1910.
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. In 1927 Wittgenstein famously designed a door handle which has become a prototype for curved tubular handles since then. Emerson wrote of handles in his "The American Scholar" address. 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.
The plate on the edge of a door (where a bolt or door plunger protrudes) is called the "faceplate"; opposite on the jamb is the "latchplate", creating or reinforcing the hole receiving a latch, bolt, or plunger.
The location of the door handle along the vertical axis on the door may vary between .
Doorknobs can be difficult for the young and elderly to operate. For this reason, door handles in most American Commerce and industrial buildings and in many households are lever-operated, rather than a knob, as the lever does not require a tight grip. Levers are also beneficial on doors with narrow stile widths where the reduced backset leaves insufficient space to comfortably turn a doorknob.
Most household door handles use a simple mechanism with a screw-style axle (called a spindle) that has at least one flat side, which is passed through the door jigger, leaving some length exposed on each side of the door to which the handles are attached. Some handles are attached on both sides by screwing or sliding them directly onto the spindle, and then securing one or more retaining screws (set screws) through the knob perpendicular to the flat of the spindle. Handles that lose traction can frequently be repaired by replacing or adjusting the set screw, which prevents them from slipping on the spindle. Other types of handles, typically used in Europe, slide onto the spindle but are affixed only to the door itself without use of set screws.
Types of household handles:
Door handles can also be called "handle sets". In addition there are door handles that are flush-mount and require pressing rather than turning or gripping, and there are touch-free, electronic, and motion-sensor door handles.
To avoid hand contact, some door handles are designed to be operated by the arm or foot.
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