Crown post

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Crown post roof in the solar at Old Soar Manor in 2009: the crown post is the upright above the tie beam. It carries a beam called the crown plate which in turn supports the collar beams. There are braces between the collar beams and common rafters and from the crown posts to these braces. Old Soar Manor - solar - geograph.org.uk - 1596419.jpg
Crown post roof in the solar at Old Soar Manor in 2009: the crown post is the upright above the tie beam. It carries a beam called the crown plate which in turn supports the collar beams. There are braces between the collar beams and common rafters and from the crown posts to these braces.
A crown post roof in the Dictionary of French Architecture from 11th to 16th Century (1856) (Dictionnaire raisonne de l'architecture francaise du XIe au XVIe siecle a French language dictionary) by Eugene Viollet-le-Duc. A. section view, B. longitudinal view, C. curved brace, D. crown post, E. cambered tie beam, F. collar plate, R collar beam. Charpente.chateau.Sully.sur.Loire.3.png
A crown post roof in the Dictionary of French Architecture from 11th to 16th Century (1856) (Dictionnaire raisonné de l’architecture française du XIe au XVIe siècle a French language dictionary) by Eugène Viollet-le-Duc. A. section view, B. longitudinal view, C. curved brace, D. crown post, E. cambered tie beam, F. collar plate, R collar beam.

A crown post is a term in traditional timber framing for a post in roof framing which stands on a tie beam or collar beam and supports a collar plate. [1] Historically, crown posts were called king posts, but this usage is confusing and obsolete. A crown post is designed to be in a compression and transfers weight to the tie beam, where a king post is designed to be in tension and supports the tie beam. In the U.K a crown strut is similar to a crown post but does not carry a plate.

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Truss Rigid structure that consists of two-force members only

A truss is an assembly of members such as beams, connected by nodes, that creates a rigid structure.

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A joist is a horizontal structural member used in framing to span an open space, often between beams that subsequently transfer loads to vertical members. When incorporated into a floor framing system, joists serve to provide stiffness to the subfloor sheathing, allowing it to function as a horizontal diaphragm. Joists are often doubled or tripled, placed side by side, where conditions warrant, such as where wall partitions require support.

Jettying Medieval building technique

Jettying is a building technique used in medieval timber-frame buildings in which an upper floor projects beyond the dimensions of the floor below. This has the advantage of increasing the available space in the building without obstructing the street. Jettied floors are also termed jetties. In the U.S., the most common surviving colonial version of this is the garrison house. Most jetties are external, but some early medieval houses were built with internal jetties.

Hammerbeam roof Type of English Gothic roof

A hammerbeam roof is a decorative, open timber roof truss typical of English Gothic architecture and has been called "...the most spectacular endeavour of the English Medieval carpenter". They are traditionally timber framed, using short beams projecting from the wall on which the rafters land, essentially a tie beam which has the middle cut out. These short beams are called hammer-beams and give this truss its name. A hammerbeam roof can have a single, double or false hammerbeam truss.

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Cruck Curved timber used as roof support

A cruck or crook frame is a curved timber, one of a pair, which support the roof of a building, historically used in England and Wales. This type of timber framing consists of long, generally naturally curved, timber members that lean inwards and form the ridge of the roof. These posts are then generally secured by a horizontal beam which then forms an "A" shape. Several of these "crooks" are constructed on the ground and then lifted into position. They are then joined together by either solid walls or cross beams which aid in preventing 'racking'.

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Wall plate A horizontal, structural, load-bearing member in wooden building framing

A plate or wall plate is a horizontal, structural, load-bearing member in wooden building framing.

Purlin

A purlin is a longitudinal, horizontal, structural member in a roof. In traditional timber framing there are three basic types of purlin: purlin plate, principal purlin, and common purlin.

Domestic roof construction

Domestic roof construction is the framing and roof covering which is found on most detached houses in cold and temperate climates. Such roofs are built with mostly timber, take a number of different shapes, and are covered with a variety of materials.

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A bressummer, breastsummer, summer beam is a load-bearing beam in a timber-framed building. The word summer derived from sumpter or French sommier, "a pack horse", meaning "bearing great burden or weight". "To support a superincumbent wall", "any beast of burden", and in this way is similar to a wall plate.

King post Central vertical post used in architectural or bridge designs

A king post is a central vertical post used in architectural or bridge designs, working in tension to support a beam below from a truss apex above.

Collar beam

A collar beam or collar is a horizontal member between two rafters and is very common in domestic roof construction. Often a collar is structural but they may be used simply to frame a ceiling. A collar beam is often called a collar tie but this is rarely correct. A tie in building construction is an element in tension rather than compression and most collar beams are designed to work in compression to keep the rafters from sagging. A collar near the bottom of the rafters may replace a tie beam and be designed to keep the rafters from spreading, thus are in tension: these are correctly called a collar tie.

Timber roof truss

A timber roof truss is a structural framework of timbers designed to bridge the space above a room and to provide support for a roof. Trusses usually occur at regular intervals, linked by longitudinal timbers such as purlins. The space between each truss is known as a bay.

A post is a main vertical or leaning support in a structure similar to a column or pillar but the term post generally refers to a timber but may be metal or stone. A stud in wooden or metal building construction is similar but lighter duty than a post and a strut may be similar to a stud or act as a brace. In the U.K. a strut may be very similar to a post but not carry a beam. In wood construction posts normally land on a sill, but in rare types of buildings the post may continue through to the foundation called an interrupted sill or into the ground called earthfast, post in ground, or posthole construction. A post is also a fundamental element in a fence. The terms "jack" and "cripple" are used with shortened studs and rafters but not posts, except in the specialized vocabulary of shoring.

American historic carpentry

American historic carpentry is the historic methods with which wooden buildings were built in what is now the United States since European settlement. A number of methods were used to form the wooden walls and the types of structural carpentry are often defined by the wall, floor, and roof construction such as log, timber framed, balloon framed, or stacked plank. Some types of historic houses are called plank houses but plank house has several meanings which are discussed below. Roofs were almost always framed with wood, sometimes with timber roof trusses. Stone and brick buildings also have some wood framing for floors, interior walls and roofs.

The Priest House is a Grade II* listed fifteenth century timber framed hall house in the centre of West Hoathly, in West Sussex, England. It is close to The Cat Inn and St Margaret's Church. It is now a museum, open to the public six days a week from March to October.

References

  1. Alcock, N. W.. Recording timber-framed buildings: an illustrated glossary. London: Council for British Archaeology, 1989. G5