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Last edited 01 Apr 2021
The term sill (or cill), refers to the lowest horizontal element of a structure or body. In the construction industry this most commonly relates to a window sill, or sometimes to the threshold of a door.
A window sill (or windowsill, sometimes referred to as a window ledge) may be formed by timber, stone, slate, brick and so on, and is located at the base of the window. It may provide structural support for the window, and on the exterior may be inclined and project beyond the surface of the wall to shed rainwater.
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