ARRIS

Arris is an architectural term that describes the sharp edge formed by the intersection of two surfaces, such as the corner of a masonry unit; the junction between two planes of plaster or any intersection of divergent architectural details. Also the raised edges which separate the flutings in a Doric column. The origin is from the Latin 'arista' meaning the beard of an ear of grain or the bone of a fish. See also arête. An arris rail is a structural element, whose cross sectional area has two sides forming a right angled triangle. Arris rails are usually made of wood, and are manufactured by cutting a 45° chamfer from both edges of a timber, at the end of the boards. They are used for structures which require joining two timbers at...