Young Black Haired Girl Undresses Her Panties Above The Couch On The Window Sill Plate With Pillows

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, and mud 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, wall plate or simply "the plate".
Timber sills
In historic buildings the sills were almost always large, solid timbers framed together at the corners and bents and 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.