Top plate

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

A plate in timber framing is "A piece of Timber upon which some considerable weight is framed...Hence Ground-Plate...Window-plate [obsolete]..." etc. Also called a wall plate,raising plate, or top plate, An exception to the use of the term plate for a large, load-bearing timber in a wall is the bressummer, a timber supporting a wall over a wall opening (see also: lintel). These are common in Australia.

The terms sole plate or sill plate are used for the members at the bottom of a wall at the foundation but are most often just called a sole or sill without the word plate. Other load bearing timbers use the term plate but are not in the wall such as crown plate, a purlin-like beam carried by crown posts in roof framing, and a purlin plate which supports common rafters.

In platform framing there are three types of wall plates and are located at the top and bottom of a wall section, and the two hold the wall studs parallel and spaced at the correct interval. Each type continues in a piecewise fashion around the whole perimeter of the structure.

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