Sill plate

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Unusual sill framing in a granary of half-timber construction. Long tenons project through the sill plate. Timber sills can span gaps in a foundation. Chalot tenons mortaises.jpg
Unusual sill framing in a granary of half-timber construction. Long tenons project through the sill plate. Timber sills can span gaps in a foundation.

A sill plate or sole plate in construction and architecture is the bottom horizontal member of a wall or building to which vertical members are attached. The word "plate" is typically omitted in America and carpenters speak simply of the "sill". Other names are ground plate, ground sill, groundsel, [1] and midnight sill. Sill plates are usually composed of lumber but can be any material. The timber at the top of a wall is often called a top plate, pole plate, mudsill, wall plate or simply "the plate".

Contents

Timber sills

An unusual barn in Schoonebeek, Netherlands with interrupted sills, the posts land directly on the padstone foundation Zicht op doorgang van de schuur - Schoonebeek - 20411613 - RCE.jpg
An unusual barn in Schoonebeek, Netherlands with interrupted sills, the posts land directly on the padstone foundation
Norwegian style framing, Kravik Mellom, Norway Kravik Mellom, detalj av fundamentet.jpg
Norwegian style framing, Kravik Mellom, Norway

In historic buildings the sills were almost always large, solid timbers framed together at the corners, carry the bents, and are set on the stone or brick foundation walls, piers, or piles (wood posts driven or set into the ground). The sill typically carries the wall framing (posts and studs) and floor joists.

There are rare examples of historic buildings in the U.S. where the floor joists land on the foundation and a plank sill or timber sill sit on top of the joists. [2] Another rare, historic building technique is for the posts of a timber-frame building to land directly on a foundation or in the ground and the sills fit between the posts and are called interrupted sills.

Stick framing

In modern wood construction, sills usually come in sizes of 2×4, 2×6, 2×8, and 2×10. In stick framing, the sill is made of treated lumber, and is anchored to the foundation wall, often with J-bolts, to keep the building from coming off the foundation during a severe storm or earthquake. Building codes require that the bottom of the sill plate be kept 6 to 8 inches above the finished grade, to hinder termites, and to prevent the sill plate from rotting.

Automobiles

In automobiles, the sill plate is located underneath the door and sometimes displays the make or model of the vehicle.

In naval architecture, sill also refers to the lower horizontal plate (frame) height, above which doors and access opening are fixed.

Related Research Articles

Lumber Wood that has been processed into beams and planks

Lumber, also known as timber, is wood that has been processed into beams and planks, a stage in the process of wood production. Lumber is mainly used for structural purposes but has many other uses as well.

Floor Walking surface of a room

A floor is the bottom surface of a room or vehicle. Floors vary from simple dirt in a cave to many-layered surfaces made with modern technology. Floors may be stone, wood, bamboo, metal or any other material that can support the expected load.

Barn Agricultural building used for storage and as a covered workplace

A barn is an agricultural building usually on farms and used for various purposes. In North America, a barn refers to structures that house livestock, including cattle and horses, as well as equipment and fodder, and often grain. As a result, the term barn is often qualified e.g. tobacco barn, dairy barn, cow house, sheep barn, potato barn. In the British Isles, the term barn is restricted mainly to storage structures for unthreshed cereals and fodder, the terms byre or shippon being applied to cow shelters, whereas horses are kept in buildings known as stables. In mainland Europe, however, barns were often part of integrated structures known as byre-dwellings. In addition, barns may be used for equipment storage, as a covered workplace, and for activities such as threshing.

Timber framing Traditional building technique

Timber framing and "post-and-beam" construction are traditional methods of building with heavy timbers, creating structures using squared-off and carefully fitted and joined timbers with joints secured by large wooden pegs. If the structural frame of load-bearing timber is left exposed on the exterior of the building it may be referred to as half-timbered, and in many cases the infill between timbers will be used for decorative effect. The country most known for this kind of architecture is Germany, where timber-framed houses are spread all over the country.

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.

Rafter Supporting structural member in roof construction

A rafter is one of a series of sloped structural members such as wooden beams that extend from the ridge or hip to the wall plate, downslope perimeter or eave, and that are designed to support the roof shingles, roof deck and its associated loads. A pair of rafters is called a couple. In home construction, rafters are normally made of wood. Exposed rafters are a feature of some traditional roof styles.

Framing (construction) Construction techique

Framing, in construction, is the fitting together of pieces to give a structure support and shape. Framing materials are usually wood, engineered wood, or structural steel. The alternative to framed construction is generally called mass wall construction, where horizontal layers of stacked materials such as log building, masonry, rammed earth, adobe, etc. are used without framing.

A tie, strap, tie rod, eyebar, guy-wire, suspension cables, or wire ropes, are examples of linear structural components designed to resist tension. It is the opposite of a strut or column, which is designed to resist compression. Ties may be made of any tension resisting material.

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.

Bressummer

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.

Wall stud

A wall stud is a vertical repetitive framing member in a building's wall of smaller cross section than a post. It is a fundamental element in frame building.

Thomas Ranck Round Barn United States historic place

The Thomas Ranck Round Barn is a round barn in Waterloo Township near the Fayette-Wayne County, Indiana county line. It is one of many round barns built in Indiana during the late 19th and early 20th centuries. Of the round barns built in eastern Indiana during this period the Ranck Round Barn stands out as one of the most elaborately designed structures. The Thomas Ranck Round Barn was listed on the U.S. National Register of Historic Places in January 1983.

King post

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.

In the framing of a deck or floor system, a rim joist is attached perpendicular to the joists, and provides lateral support for the ends of the joists while capping off the end of the floor or deck system. Rim joists are not to be confused with end joists, which are the first and last joists at the ends of a row of joists that make up a floor or deck frame.

Mitchell – Foster – Young House United States historic place

The Mitchell – Foster – Young House is a historic house located just outside Oxford, Mississippi off the highway to New Albany. The house, thought to be one of the oldest standing farmhouses in the county, is listed on the National Register of Historic Places.

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.

New England barn

The New England Barn was the most common style of barn built in most of the 19th century in rural New England and variants are found throughout the United States. This style barn superseded the ”three-bay barn” in several important ways. The most obvious difference is the location of the barn doors on the gable-end(s) rather than the sidewall(s). The New England and three bay barns were used similarly as multipurpose farm buildings but the New England barns are typically larger and have a basement. Culturally the New England Barn represents a shift from subsistence farming to commercial farming thus are larger and show significant changes in American building methods and technologies. Most were used as dairy barns but some housed teams of oxen which are generally called teamster barns. Sometimes these barns are simply called “gable fronted” and “gable fronted bank barns” but these terms are also used for barns other than the New England style barn such as in Maryland and Virginia which is not exactly the same style as found in New England. A similar style found in parts of the American mid-west and south is called a transverse frame barn or transverse crib barn.

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.

References

  1. Oxford English Dictionary Ground sill
  2. Sobon, Jack A.. Historic American timber joinery: a graphic guide. Fourth printing. ed. Becket: Timber Framers Guild, 2010. pp 21, 22.