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Door

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A door is a movable barrier designed for ingress and egress. Ingress refers to the act of entering a space. Egress refers to the act of exiting a space.

L-door
L-door

The opening in a wall that the door fills is called a doorway or a portal. The primary purpose of a door is to provide security. It does this by controlling access to the portal. Doors are typically panels that fit into the frame of a building, a room, or a vehicle.

Panel door
Panel door

Doors move through several different mechanical processes. Most commonly, they are attached by hinges to swing at an angle. Some doors operate by sliding on a plane parallel to the frame. Others may fold in angles on a parallel plane. Some doors even spin along an axis at the center of the frame.

Types of doors
Types of doors

Many doors incorporate locking mechanisms. These allow only specific people to enter, often using a key. People also use devices like knockers or doorbells to announce their presence to those inside.

Beyond basic access, doors serve many secondary functions. They provide privacy by preventing unwanted attention from outsiders. They can separate areas that have different functions. Doors also manage the environment inside a building. They can allow light to pass through or control ventilation to manage air drafts. This helps to heat or cool an interior more effectively. Furthermore, doors can dampen noise or help block the spread of fire.

Construction methods vary based on the materials used. A standard door often uses a frame and panel design. This includes vertical boards called stiles and horizontal pieces called rails.

The hanging stile is the vertical board that is attached to the frame. The meeting stile is the vertical board that meets the other door in a double-door setup. The horizontal pieces include the top rail, the bottom rail, and middle rails. These rails hold the panels, known as tympana, which are set into grooves within the stiles and rails.

History shows a long evolution of door design and material. The earliest recorded doors appear in Egyptian tomb paintings. These were often single or double doors made of single pieces of wood. In Egypt, the dry climate meant doors did not need to be framed against warping. In other regions, framing was necessary to keep the wood stable. Archaeologists have discovered doors near Zürich, Switzerland, that are over 5,000 years old. Ancient builders used various timbers, including olive, elm, cedar, oak, and cypress.

Technological milestones have changed how doors function. In the first century AD, Heron of Alexandria created the earliest known automatic door. Much later, the first foot-sensor-activated automatic door was built in China. This was installed for the library of Emperor Yang of Sui between 604 and 618 AD.

Plaster cast of folding doors, Pompeii
Plaster cast of folding doors, Pompeii

During the Middle Ages, bronze became a popular material for decorative doors. One famous example is the "Gates of Paradise" in Florence. These gilded bronze doors were completed by Ghiberti between 1425 and 1452.

Florença - Portões do Paraíso (146)
Florença - Portões do Paraíso (146)

Doors also hold deep symbolic and social meaning. Receiving a key to a door can signify a change in status. It can represent a transition from an outsider to an insider. In literature and art, doors often serve as metaphors for change. They can be ritualistic or aesthetic objects. Even the size of a door can be significant. For example, NASA's Vehicle Assembly Building contains four of the largest doors in existence. These massive doors were built to support the assembly of Apollo Saturn vehicles and Space Shuttle operations.

Today, we categorize doors by their specific configurations. A single-leaf door is a single rigid panel. A double-leaf door, or double door, uses two adjacent panels hinged on each side.

Kunsthistorisches Museum entrance
Kunsthistorisches Museum entrance

There are also Dutch doors, which are divided horizontally. This allows the top half to open while the bottom remains closed. This design was traditionally used so workers could feed animals without the animal escaping. From small residential panels to massive industrial gates, doors remain essential to how we organize our world.

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🖼️ Images & Media (16)
File:L-door.png
L-door.png
File:Plaster cast of folding doors, Pompeii.jpg
Plaster cast of folding doors, Pompeii.jpg
File:Tür, Villa Boscoreale.jpg
Tür, Villa Boscoreale.jpg
File:Дом компании Зингер, Россия, Санкт-Петербург.JPG
Дом компании Зингер, Россия, Санкт-Петербург.JPG
File:Florença - Portões do Paraíso (146).jpg
Florença - Portões do Paraíso (146).jpg
File:Kunsthistorisches Museum entrance.jpg
Kunsthistorisches Museum entrance.jpg
File:Types of doors.png
Types of doors.png
File:Puertas seccionales.jpg
Puertas seccionales.jpg
File:Miersch, 17 rue Nicolas Welter-001.jpg
Miersch, 17 rue Nicolas Welter-001.jpg
File:Door-glossary.png
Door-glossary.png
File:Door-midrail-detail.png
Door-midrail-detail.png
File:Frame-filled-door.gif
Frame-filled-door.gif

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