Door

The front door of a house is often decorated to appear inviting.

A door is a moveable barrier used to cover an opening. Doors are widely used and are found in walls or partitions of a building, vehicles, and furniture such as cupboards, cages, and containers. A door can be opened to give access and closed more or less securely using a combination of latches and locks. (See article Door security). Doors are nearly universal in buildings of all kinds, allowing passage between the inside and outside, and between internal rooms. When open, they admit ventilation and light. The door is used to control the physical atmosphere within a space by enclosing it, excluding air drafts, so that interiors may be more effectively heated or cooled. Doors are significant in preventing the spread of fire. They act as a barrier to noise. (See article Door safety).

They are also used to screen areas of a building for aesthetics, keeping formal and utility areas separate. Doors also have an aesthetic role in creating an impression of what lies beyond. Doors are often symbolically endowed with ritual purposes, and the guarding or receiving of the keys to a door, or being granted access to a door can have special significance.[1] Similarly, doors and doorways frequently appear in metaphorical or allegorical situations, literature and the arts, often as a portent of change.

Contents

Applications

One of the ornate doors inside the Great Mosque of Kairouan also known as the Mosque of Uqba, city of Kairouan, Tunisia. The door served as a primary defense for the building.

Architectural doors have numerous general and specialized uses. Doors are generally used to separate interior spaces (rooms, closets, etc.) for privacy, convenience, security, and safety reasons. Doors are also used to secure passages into a building from the exterior for reasons of safety and climate control.

Doors also are applied in more specialized cases:

Design and styles

A decorated door from the Tibetan Namdroling monastery, southern India.
Door of Florence's Baptistery called Gates of Paradise
Door in rural Punjab

Many kinds of doors have specific names, depending on their purpose. The most common variety of door is the single-leaf door which consists of a single rigid panel that fills the doorway. Many variations on this basic design are possible, such as the double-leaf door or double doors and french doors that have two adjacent independent panels hinged on each side of the doorway.

A half door or Dutch door or stable door is divided in half horizontally. Traditionally the top half can be opened to allow a horse or other animal to be fed, while the bottom half remained closed to keep the animal inside. This style of door has been adapted for homes.

Saloon doors are a pair of lightweight swing doors often found in public bars, and especially associated with the American west. Saloon doors, also known as cafe doors, often use bidirectional hinges which close the door regardless of which direction it is opened by incorporating springs. Saloon doors that only extend from knee-level to chest-level are known as batwing doors.

A blind door or Gibb door is a door with no visible trim or operable components. It is designed to blend with the adjacent wall in all finishes, and visually to be a part of the wall, a disguised door.

A barn door is a door characteristic of a barn. They are often/always found on barns, and because of a barn's immense size (often) doors are subsequently big for utility.

A French door, also called a French window, is a door comprising a pair of full-height casement windows. The main framing is detailed without a central mullion to allow easy passage though the doorway and each casement is fully glazed often with multiple panes ("lights"). The frame typically requires a weather strip at floor level and where the casements meet to prevent water ingress. An espagnolette bolt allows the head and foot of each casements to be secured in one movement. The slender window joinery maximises light though into the room and minimises the visual impact of the doorway joinery when considered externally.

A louvred door has fixed or movable wooden fins (often called slats or louvers) which permit open ventilation while preserving privacy and preventing the passage of light to the interior. Being relatively weak structures, they are most commonly used for wardrobes and drying rooms, where security is of less importance than good ventilation, although a very similar structure is commonly used to form window shutters.

A composite door is a single leaf door that can be solid or with glass, and is usually filled with high density foam. Most composite doors carry secured by design accreditation and PAS 23 and PAS 24.

A flush door is a completely smooth door, having plywood or MDF fixed over a light timber frame, the hollow parts of which are often filled with a cardboard core material. Skins can also be made out of hardboards, the first of which was invented by William H Mason in 1924. Called Masonite, its construction involved pressing and steaming wood chips into boards. Flush doors are most commonly employed in the interior of a dwelling, although slightly more substantial versions are occasionally used as exterior doors, especially within hotels and other buildings containing many independent dwellings.

A moulded door has the same structure as that of flush door. The only difference is that the surface material is a moulded skin made of MDF. Skins can also be made out of hardboards, the first of which was invented by William H Mason in 1924. Called Masonite, its construction involved pressing and steaming wood chips into boards. Molded doors are commonly used as interior doors.

A ledge and brace door is a door made from multiple vertical planks fixed together by two horizontal planks (the ledges) and kept square by a diagonal plank (the brace).

A wicket door is a pedestrian door built into a much larger door allowing access without requiring the opening of the larger door. Examples might be found on the ceremonial door of a cathedral or in a large vehicle door in a garage or hangar.

A bifold door is a door unit that has several sections, folding in pairs. Wood is the most common material, and doors may also be metal or glass. Bifolds are most commonly made for closets, but may also be used as units between rooms.

A sliding glass door, sometimes called an Arcadia door, is a door made of glass that slides open and sometimes has a screen.

Australian doors are a pair of plywood swinging doors often found in Australian public houses. These doors are generally red or brown in color and bear a resemblance to the more formal doors found in other British Colonies' public houses.

A false door is a wall decoration that looks like a door. In ancient Egyptian architecture, this was a common element in a tomb, the false door representing a gate to the afterlife. They can also be found in the funerary architecture of the desert tribes (e.g., Libyan Ghirza).

Types of mechanism

The main types of door mechanisms

Hinged doors

Most doors are hinged along one side to allow the door to pivot away from the doorway in one direction but not in the other. The axis of rotation is usually vertical. In some cases, such as hinged garage doors, the axis may be horizontal, above the door opening.

Doors can be hinged so that the axis of rotation is not in the plane of the door to reduce the space required on the side to which the door opens. This requires a mechanism so that the axis of rotation is on the side other than that in which the door opens. This is sometimes the case in trains, such as for the door to the toilet, which opens inward.

A swing door has special hinges that allow it to open either outwards or inwards, and is usually sprung to keep it closed.

A selfbolting door is called as such because of its special hinges that permit the panel leaf to move laterally so that the door itself becomes a giant bolt for better security result. The selfbolting door principle can be used both for hinged doors as for rotating doors, as well as up-and-over doors (in the latter case, the bolts are then placed at top and bottom rather than at the sides).

French doors are derived from an original French design called the casement door. It is basically a double-leaved door with large glass panels in each door leaf, and in which the doors can swing both out as well as in. French doors traditionally have a moulded panel at the bottom of the door.

Sliding doors

It is often useful to have doors which slide along tracks, often for space or aesthetic considerations.

A bypass door is a door unit that has two or more sections. The doors can slide in either direction along one axis on parallel overhead tracks, sliding past each other. They are most commonly used in closets, in order to access one side of the closet at a time. The doors in a bypass unit will overlap slightly when viewed from the front, in order not to have a visible gap between them.

Doors which slide between two wall panels are called pocket doors.

Sliding glass doors are common in many houses, particularly as an entrance to the backyard. Such doors are also popular for use for the entrances to commercial structures.

Folding doors

Folding doors (also known as accordion doors) have multiple panels which fold upon one another when such doors are opened. These doors are often used to cover a broad space where a straight door’s swing would be cumbersome or restricted. Folding doors combine the actions of both hinged and slider doors, and use both end pivots and overhead tracks.

Rotating doors

A revolving door normally has four wings/leaves that hang on a center shaft and rotate one way about a vertical axis. The door may be motorized, or pushed manually using pushbars. People can walk out of and into the building at the same time. Between the point of access and the point of exit the user walks through an airlock. Revolving doors therefore create a good seal from the outside and help to reduce A/C and heating costs climate control from the building. This type of door is also often seen as a mark of prestige and glamour for a building and it not unusual for neighbouring buildings to install their own revolving doors when a rival building gets one.

A butterfly door called because of its two "wings". It consists of a double-wide panel with its rotation axle in the centre, effectively creating two separate openings when the door is opened. Butterfly doors are made to rotate open in one direction (usually counterclockwise), and rotate closed in the opposite direction. The door is not equipped with handles, so it is a "push" door. This is for safety, because if it could open in both directions, someone approaching the door might be caught off-guard by someone else opening the other side, thus impacting the first person. Such doors are popular in public transit stations, as it has a large capacity, and when the door is opened, traffic passing in both directions keeps the door open. They are particularly popular in underground subway stations, because they are heavy, and when air currents are created by the movement of trains, the force will be applied to both wings of the door, thus equalizing the force on either side, keeping the door shut.

Others

A up-and-over door mechanism with counterweight

Up-and-over or overhead doors are often used in garages. Instead of hinges it has a mechanism, often counterbalanced or sprung, that allows it to be lifted so that it rests horizontally above the opening. A roller shutter or sectional overhead door is one variant of this type.

A tambour door is an up-and-over door made of narrow horizontal slats and "rolls" up and down by sliding along vertical tracks and is typically found in entertainment centres and cabinets.

Automatic doors are powered open and closed either by electricity, spring, or both. There are several methods by which an automatic door is activated:

  1. A sensor detects traffic is approaching. Sensors for automatic doors are generally:
    • A pressure sensor - e.g., a floor mat which reacts to the pressure of someone standing on it.
    • An infrared curtain or beam which shines invisible light onto sensors; if someone or something blocks the beam the door is triggered open.
    • A motion sensor which uses low-power microwave radar for the same effect.
    • A remote sensor (e.g. based on infrared or radio waves) can be triggered by a portable remote control, or is installed inside a vehicle. These are popular for garage doors.
  2. A switch is operated manually, perhaps after security checks. This can be a push button switch or a swipe card.
  3. The act of pushing or pulling the door triggers the open and close cycle. These are also known as power-assisted doors.

In addition to activation sensors automatic doors are generally fitted with safety sensors. These are usually an infrared curtain or beam, but can be a pressure mat fitted on the swing side of the door. The purpose of the safety sensor is to prevent the door from colliding with an object in its path by stopping or slowing its motion.

Inward opening doors are doors that can only be opened (or forced open) from outside a building. Such doors pose a substantial fire risk to occupants of occupied buildings when they are locked. As such doors can only be forced open from the outside, building occupants would be prevented from escaping. In commercial and retail situations manufacturers have included in the design a mechanism that allows an inward opening door to be pushed open outwards in the event of an emergency (which is often a regulatory requirement). This is known as a 'breakaway' feature. Pushing the door outward at its closed position, through a switch mechanism, disconnects power to the latch and allows the door to swing outward. Upon returning the door to the closed position, power is restored. The automatic doors were invented by a company called Grupsa System in Spain.

Rebated doors, a term chiefly used in Britain, are double doors having a lip (i.e. a Rabbet) on the vertical edge where they meet. [2]

Door construction and components

Parts of a panel and or glazed door
joint between midrail, lockrail and a gunstock stile
A frame and filled door
A hollow door with one face removed

Panel doors

Panel doors, also called stile and rail doors, are built with frame and panel construction:

Plank and batten doors

Plank and batten doors are an older design consisting primarily of vertical slats:

Ledged and braced doors

This type consists of vertical tongue and grooved boards held together with battens and diagonal braces.

Frame and filled doors

This type consists of a solid timber frame, filled on one face, face with Tongue and Grooved boards. Quite often used externally with the boards on the weather face.

Flush doors

Many modern doors, including most interior doors, are flush doors:

Moulded doors

Swing direction

Door swing directions diagram.

Door swings For most of the world, door swings, or handing, are determined while standing on the outside or less secure side of the door while facing the door (i.e., standing on the side you use the key on, going from outside to inside, or from public to private).

It is especially important to get the hand and swing right on exterior doors, as the transom is usually sloped and sealed to resist water entry, and to properly drain. In some custom millwork (or with some master carpenters), the manufacture or installer will bevel the leading edge (the first edge to meet the jamb as the door is closing) so that the door fits tight without binding. Specifying an incorrect hand and/or swing will cause the door to bind, not close properly, or leak (for exterior doors). Fixing this specification error will be expensive and/or time consuming. See note below for Australia where a different orientation is used.

In North America, many doors now come with factory-installed hinges, pre-hung on the jamb and sills.

To determine hand, stand on the outside (or less secure) side of the door. While facing the door, if the hinge is on the right side of the door, the door is "Right handed"; or if the hinge is on the left, it is "Left handed".

If the door swings toward you, it is "Reverse swing"; or if the door swings away from you, it is "Normal swing".

In other words:

Note: In Australia, this is different. The refrigerator rule applies (you can't stand in a fridge, the door always opens towards you) - If the hinges are on the left then its a left hand (or left hung) door. If the hinges are on the right then its a right hand (or right hung) door. See the Australian Standards for Installation of Timber Doorsets, AS 1909-1984 pg 6.

Dimensions

A standard US door size 36" x 80" (0.91 m x 2.03 m).

Exterior and passage (room to room) doors: Standard door sizes in the US are from 2'6" to 3' wide, increasing in 2" increments. Most residential interior doors are 2'6" wide except when designed to allow wheelchair access, then 3'. Residential doors are 6'8" high, as are many small stores, offices, and other light commercial buildings. Larger commercial and public buildings often use doors of greater height. Older buildings often have smaller doors.

Closets: small spaces such as closets, dressing rooms, half-baths, storage rooms, cellars, etc. often are accessed through doors smaller than passage doors in one or both dimensions but similar in design.

Garages: Garage doors are generally 7' or 8' wide for a single-car opening.

A diagram illustrating the components of a panel door

Doorway components

When framed in wood for snug fitting of a door, the doorway consists of two vertical jambs on either side, a lintel or head jamb at the top, and perhaps a threshold at the bottom. When a door has more than one movable section, one of the sections may be called a leaf. See door furniture for a discussion of attachments to doors such as door handles and doorknobs.

Related hardware

See main article: Door furniture

Door furniture or hardware refers to any of the items that are attached to a door or a drawer to enhance its functionality or appearance. This includes items such as hinges, handles, door stops, etc.

History

An old door (20th Century CE), Kashan, Iran

The earliest records are those represented in the paintings of the Egyptian tombs, in which they are shown as single or double doors, each in a single piece of wood. In Egypt, where the climate is intensely dry, there would be no fear of their warping, but in other countries it would be necessary to frame them, which according to Vitruvius (iv. 6.) was done with stiles (sea/si) and rails (see: Frame and panel): the spaces enclosed being filled with panels (tympana) let into grooves made in the stiles and rails. The stiles were the vertical boards, one of which, tenoned or hinged, is known as the hanging stile, the other as the middle or meeting stile. The horizontal cross pieces are the top rail, bottom rail, and middle or intermediate rails. The most ancient doors were in timber, those made for King Solomon's temple being in olive wood (I Kings vi. 31-35), which were carved and overlaid with gold. The doors dwelt upon in Homer would appear to have been cased in silver or brass. Besides Olive wood, elm, cedar, oak and cypress were used.

Stone door, Hampi, India

All ancient doors were hung by pivots at the top and bottom of the hanging stile which worked in sockets in the lintel and sill, the latter being always in some hard stone such as basalt or granite. Those found at Nippur by Dr. Hilprecht, dating from 2000 B.C. were in dolerite. The tenons of the gates at Balawat were sheathed with bronze (now in the British Museum). These doors or gates were hung in two leaves, each about 8 ft 4 in (2.54 m) wide and 27 ft (8.2 m). high; they were encased with bronze bands or strips, 10 in. high, covered with repouss decoration of figures, etc. The wood doors would seem to have been about 3 in. thick, but the hanging stile was over 14 inches (360 mm) diameter. Other sheathings of various sizes in bronze have been found, which proves this to have been the universal method adopted to protect the wood pivots. In the Hauran in Syria, where timber is scarce the doors were made in stone, and one measuring 5 ft 4 in (1.63 m) by 2 ft 7 in (0.79 m) is in the British Museum; the band on the meeting stile shows that it was one of the leaves of a double door. At Kuffeir near Bostra in Syria, Burckhardt found stone doors, 9 to 10 ft (3.0 m). high, being the entrance doors of the town. In Etruria many stone doors are referred to by Dennis.

Roman folding doors at Pompeii (1st century CE).

The ancient Greek and Roman doors were either single doors, double doors, sliding doors or folding doors, in the last case the leaves were hinged and folded back. In Eumachia, is a painting of a door with three leaves. In the tomb of Theron at Agrigentum there is a single four-panel door carved in stone. In the Blundell collection is a bas-relief of a temple with double doors, each leaf with five panels. Among existing examples, the bronze doors in the church of SS. Cosmas and Damiano, in Rome, are important examples of Roman metal work of the best period; they are in two leaves, each with two panels, and are framed in bronze. Those of the Pantheon are similar in design, with narrow horizontal panels in addition, at the top, bottom and middle. Two other bronze doors of the Roman period are in the Lateran Basilica.

Heron of Alexandria created the earliest known automatic door in the 1st century CE during the era of Roman Egypt.[3] The first foot-sensor-activated automatic door was made in China during the reign of Emperor Yang of Sui (r. 604–618), who had one installed for his royal library.[3] The first automatic gate operators were later created in 1206 by the Arabic inventor, Al-Jazari.[4]

The doors of the church of the Nativity at Bethlehem (6th century) are covered with plates of bronze, cut out in patterns: those of Hagia Sophia at Constantinople, of the 8th and 9th century, are wrought in bronze, and the west doors of the cathedral of Aix-la-Chapelle (9th century), of similar manufacture, were probably brought from Constantinople, as also some of those in St. Marks, Venice.

Ornate door. Roman wall painting in the Villa Boscoreale, Italy (1st century CE).

Of the 11th and 12th centuries there are numerous examples of bronze doors, the earliest being one at Hildesheim, Germany (1015). The Hildesheim design affected the concept of Gniezno door in Poland. Of others in South Italy and Sicily, the following are the finest: in Sant Andrea, Amalfi (1060); Salerno (1099); Canosa (1111); Troia, two doors (1119 and 1124); Ravello (1179), by Barisano of Trani, who also made doors for Trani cathedral; and in Monreale and Pisa cathedrals, by Bonano of Pisa. In all these cases the hanging stile had pivots at the top and bottom. The exact period when the hinge was substituted is not quite known, but the change apparently brought about another method of strengthening and decorating doors, viz, with wrought-iron bands of infinite varieties of design. As a rule three bands from which the ornamental work springs constitute the hinges, which have rings outside the hanging stiles fitting on to vertical tenons run into the masonry or wooden frame. There is an early example of the 12th century in Lincoln; in France the metal work of the doors of Notre Dame at Paris is perhaps the most beautiful in execution, but examples are endless throughout France and England.

Returning to Italy, the most celebrated doors are those of the Battistero di San Giovanni (Florence), which together with the door frames are all in bronze, the borders of the latter being perhaps the most remarkable: the modeling of the figures, birds and foliage of the south doorway, by Andrea Pisano (1330), and of the east doorway by Ghiberti (1425-1452), are of great beauty; in the north door (1402-1424) Ghiberti adopted the same scheme of design for the paneling and figure subjects in them as Andrea Pisano, but in the east door the rectangular panels are all filled, with bas-reliefs, in which Scripture subjects are illustrated with innumerable figures, these being probably the gates of Paradise of which Michelangelo speaks.

An old door (20th Century CE), Isfahan, Iran

The doors of the mosques in Cairo were of two kinds; those which, externally, were cased with sheets of bronze or iron, cut out in decorative patterns, and incised or inlaid, with bosses in relief; and those in wood, which were framed with interlaced designs of the square and diamond, this latter description of work being Coptic in its origin. The doors of the palace at Palermo, which were made by Saracenic workmen for the Normans, are fine examples and in good preservation. A somewhat similar decorative class of door to these latter is found in Verona, where the edges of the stiles and rails are beveled and notched.

In the Renaissance period the Italian doors are quite simple, their architects trusting more to the doorways for effect; but in France and Germany the contrary is the case, the doors being elaborately carved, especially in the Louis XIV and Louis XV periods, and sometimes with architectural features such as columns and entablatures with pediment and niches, the doorway being in plain masonry. While in Italy the tendency was to give scale by increasing the number of panels, in France the contrary seems to have been the rule; and one of the great doors at Fontainebleau, which is in two leaves, is entirely carried out as if consisting of one great panel only.

The earliest Renaissance doors in France are those of the cathedral of St. Sauveur at Aix (1503). In the lower panels there are figures 3 ft (0.91 m). high in Gothic niches, and in the upper panels a double range of niches with figures about 2 ft (0.61 m). high with canopies over them, all carved in cedar. The south door of Beauvais Cathedral is in some respects the finest in France; the upper panels are carved in high relief with figure subjects and canopies over them. The doors of the church at Gisors (1575) are carved with figures in niches subdivided by classic pilasters superimposed. In St. Maclou at Rouen are three magnificently carved doors; those by Jean Goujon have figures in niches on each side, and others in a group of great beauty in the center. The other doors, probably about forty to fifty years later, are enriched with bas-reliefs, landscapes, figures and elaborate interlaced borders.

The oldest door in England can be found in Westminster Abbey and dates from 1050.[5] In England in the 17th century the door panels were raised with bolection or projecting moldings, sometimes richly carved, round them; in the 18th century the moldings worked on the stiles and rails were carved with the egg and tongue ornament.

See also

  • Janus, Roman god of doors
  • Access badge
  • Access control
  • Alarm
  • Alarm management
  • Bank vault
  • Biometrics
  • Burglar alarm
  • Castle
  • Cat flap
  • ID Card
  • IP video surveillance
  • Keycards
  • Locksmithing
  • Lock picking
  • Logical security
  • Magnetic stripe card
  • Optical turnstile
  • Paper honeycomb
  • Photo identification
  • Physical Security Professional
  • Prison
  • Proximity card
  • Razor wire
  • Roller shutter
  • Safe
  • Safe-cracking
  • Security
  • Security engineering
  • Security lighting
  • Security policy
  • Smart card
  • Surveillance
  • Swipe card
  • Wiegand effect

References

  1. ↑ See, for example the doorkeeping duties of the Gentleman Usher of the Black Rod.
  2. ↑ Rebated doors
  3. ↑ 3.0 3.1 Needham, Joseph. (1986). Science and Civilization in China: Volume 4, Part 2, Mechanical Engineering. Taipei: Caves Books, Ltd.
  4. ↑ Howard R. Turner (1997), Science in Medieval Islam: An Illustrated Introduction, p. 181, University of Texas Press, ISBN 0-292-78149-0.
  5. ↑ "Abbey oak door 'Britain's oldest'". BBC News. 2005-08-03. http://news.bbc.co.uk/1/hi/uk/4743899.stm. Retrieved 2010-05-01.