Astragal

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Astragal architectural element as part of a Doric order column Astragal architectural element MH.jpg
Astragal architectural element as part of a Doric order column
Diagram of an astragalus profile as part of an Ionic order column Schema.astragale.png
Diagram of an astragalus profile as part of an Ionic order column

An astragal is a moulding profile composed of a half-round surface surrounded by two flat planes (fillets).[ clarification needed ] An astragal is sometimes referred to as a miniature torus. It can be an architectural element used at the top or base of a column, but is also employed as a framing device on furniture and woodwork.

The word "astragal" comes from the Greek for "ankle-joint", ἀστράγαλος, astrágalos. [1]

On doors

An astragal is commonly used to seal between a pair of doors. The astragal closes the clearance gap created by bevels on one or both mating doors, and helps deaden sound. The vertical member (molding) attaches to a stile on one of a pair of either sliding or swinging doors, against which the other door seals when closed. Exterior astragals are kerfed for weatherstripping. The weatherstripping at the bottom of garage doors is also referred to as an astragal.

An astragal may also be known as a "meeting stile seal". It is sometimes confused with the wooden trim that divides the panes of a multi-light window or door, known as a muntin.

Between the 1600 - 1800's glass was very expensive and windows were made by blowing glass and then spinning into a large circular flat plate. Once the glass was cooled it was cut into small panes. The central piece which had been attached to the blowing iron called the bulls eye was the cheapest part of the glass. It wasn't until Float glass was invented in the 1950's, where glass is poured onto a molten tin layer where it floated and gave a smooth and flat finish, that large panes of glass became more readily affordable.

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<span class="mw-page-title-main">Door</span> Movable barrier that allows ingress and egress

A door is a hinged or otherwise movable barrier that allows ingress (entry) into and egress (exit) from an enclosure. The created opening in the wall is a doorway or portal. A door's essential and primary purpose is to provide security by controlling access to the doorway (portal). Conventionally, it is a panel that fits into the doorway of a building, room, or vehicle. Doors are generally made of a material suited to the door's task. They are commonly attached by hinges, but can move by other means, such as slides or counterbalancing.

<span class="mw-page-title-main">Window</span> Opening to admit light or air

A window is an opening in a wall, door, roof, or vehicle that allows the exchange of light and may also allow the passage of sound and sometimes air. Modern windows are usually glazed or covered in some other transparent or translucent material, a sash set in a frame in the opening; the sash and frame are also referred to as a window. Many glazed windows may be opened, to allow ventilation, or closed, to exclude inclement weather. Windows may have a latch or similar mechanism to lock the window shut or to hold it open by various amounts.

<span class="mw-page-title-main">Glassblowing</span> Technique for forming glass

Glassblowing is a glassforming technique that involves inflating molten glass into a bubble with the aid of a blowpipe. A person who blows glass is called a glassblower, glassmith, or gaffer. A lampworker manipulates glass with the use of a torch on a smaller scale, such as in producing precision laboratory glassware out of borosilicate glass.

<span class="mw-page-title-main">Float glass</span> Material; type of glass

Float glass is a sheet of glass made by floating molten glass on a bed of molten metal of a low melting point, typically tin, although lead was used for the process in the past. This method gives the sheet uniform thickness and a very flat surface.

<span class="mw-page-title-main">Shoji</span> Japanese sliding paper door

A shoji is a door, window or room divider used in traditional Japanese architecture, consisting of translucent sheets on a lattice frame. Where light transmission is not needed, the similar but opaque fusuma is used. Shoji usually slide, but may occasionally be hung or hinged, especially in more rustic styles.

<span class="mw-page-title-main">Molding (decorative)</span> Class of decorative elements in the ornamentation

Moulding, or molding, also coving, is a strip of material with various profiles used to cover transitions between surfaces or for decoration. It is traditionally made from solid milled wood or plaster, but may be of plastic or reformed wood. In classical architecture and sculpture, the moulding is often carved in marble or other stones. In historic architecture, and some expensive modern buildings, it may be formed in place with plaster.

<span class="mw-page-title-main">Frame and panel</span> Wood construction in which a panel is enclosed in a rigid frame

Frame and panel construction, also called rail and stile, is a woodworking technique often used in the making of doors, wainscoting, and other decorative features for cabinets, furniture, and homes. The basic idea is to capture a 'floating' panel within a sturdy frame, as opposed to techniques used in making a slab solid wood cabinet door or drawer front, the door is constructed of several solid wood pieces running in a vertical or horizontal direction with exposed endgrains. Usually, the panel is not glued to the frame but is left to 'float' within it so that seasonal movement of the wood comprising the panel does not distort the frame.

<span class="mw-page-title-main">Fire door</span> Fire resistant door

A fire door is a door with a fire-resistance rating used as part of a passive fire protection system to reduce the spread of fire and smoke between separate compartments of a structure and to enable safe egress from a building or structure or ship. In North American building codes, it, along with fire dampers, is often referred to as a closure, which can be derated compared against the fire separation that contains it, provided that this barrier is not a firewall or an occupancy separation. In Europe national standards for fire doors have been harmonised with the introduction of the new standard EN 16034, which refers to fire doors as fire-resisting door sets. Starting September 2016, a common CE marking procedure was available abolishing trade barriers within the European Union for these types of products. In the UK, it is Part B of the Building Regulations that sets out the minimum requirements for the fire protection that must be implemented in all dwellings this includes the use of fire doors. All fire doors must be installed with the appropriate fire resistant fittings, such as the frame and door hardware, for it to fully comply with any fire regulations.

This page is a glossary of architecture.

<span class="mw-page-title-main">Architectural glass</span>

Architectural glass is glass that is used as a building material. It is most typically used as transparent glazing material in the building envelope, including windows in the external walls. Glass is also used for internal partitions and as an architectural feature. When used in buildings, glass is often of a safety type, which include reinforced, toughened and laminated glasses.

<span class="mw-page-title-main">Tempered glass</span> Type of safety glass processed to increase its strength

Tempered or toughened glass is a type of safety glass processed by controlled thermal or chemical treatments to increase its strength compared with normal glass. Tempering puts the outer surfaces into compression and the interior into tension. Such stresses cause the glass, when broken, to shatter into small granular chunks instead of splintering into jagged shards as ordinary annealed glass does. The granular chunks are less likely to cause injury.

<span class="mw-page-title-main">Leadlight</span> Type of windows

Leadlights, leaded lights or leaded windows are decorative windows made of small sections of glass supported in lead cames. The technique of creating windows using glass and lead came to be known as came glasswork. The term 'leadlight' could be used to describe any window in which the glass is supported by lead, but traditionally, a distinction is made between stained glass windows and leadlights; the former is associated with the ornate coloured-glass windows of churches and similar buildings, while the latter is associated with the windows of vernacular architecture and defined by its simplicity.

<span class="mw-page-title-main">Muntin</span> Strip of wood or metal that separates and holds glass panes in a window

A muntin (US), muntin bar, glazing bar (UK), or sash bar is a strip of wood or metal separating and holding panes of glass in a window. Muntins can be found in doors, windows, and furniture, typically in Western styles of architecture. Muntins divide a single window sash or casement into a grid system of small panes of glass, called "lights" or "lites".

Weatherstripping is the process of sealing openings such as doors, windows, and trunks from the waters above. The term can also refer to the materials used to carry out such sealing processes. The goal of weatherstripping is to prevent rain and water from entering entirely or partially and accomplishes this by either returning or rerouting water. A secondary goal of weatherstripping is to keep interior air in, thus saving energy on heating and air conditioning.

Glass production involves two main methods – the float glass process that produces sheet glass, and glassblowing that produces bottles and other containers. It has been done in a variety of ways during the history of glass.

<span class="mw-page-title-main">Casement window</span> Window that is attached to its frame by one or more hinges

A casement window is a window that is attached to its frame by one or more hinges at the side. They are used singly or in pairs within a common frame, in which case they are hinged on the outside. Casement windows are often held open using a casement stay. Windows hinged at the top are referred to as awning windows, and ones hinged at the bottom are called hoppers.

<span class="mw-page-title-main">Thomas R. McGuire House</span> Historic house in Arkansas, United States

Heated glass is a resistance heater created when a transparent, electrically conductive coating is applied to float glass and then subjected to an electric current. The electric current in the coating creates heat energy, which warms the glass until the glass radiates heat.

<span class="mw-page-title-main">Glazing (window)</span> Part of a wall or window, made of glass

Glazing, which derives from the Middle English for 'glass', is a part of a wall or window, made of glass. Glazing also describes the work done by a professional "glazier". Glazing is also less commonly used to describe the insertion of ophthalmic lenses into an eyeglass frame.

<span class="mw-page-title-main">Insulated glazing</span> Construction element consisting of at least two glass plates

Insulating glass (IG) consists of two or more glass window panes separated by a space to reduce heat transfer across a part of the building envelope. A window with insulating glass is commonly known as double glazing or a double-paned window, triple glazing or a triple-paned window, or quadruple glazing or a quadruple-paned window, depending upon how many panes of glass are used in its construction.

References

  1. Wikisource-logo.svg One or more of the preceding sentences incorporates text from a publication now in the public domain :  Chisholm, Hugh, ed. (1911). "Astragal". Encyclopædia Britannica . Vol. 2 (11th ed.). Cambridge University Press. p. 794.