Summer beam

A bressummer, breastsummer, summer beam (somier, sommier, sommer, somer, cross-somer, summer, summier, summer-tree, or dorman, dormant tree) are load bearing beams 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.

The use and definition of these terms vary but generally a bressummer is a jetty sill and a summer is an interior beam supporting ceiling joists, see below:

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