Hiuchibari

What hiuchibari means

A hiuchibari is a short diagonal member that joins two horizontal timbers meeting at right angles, such as an eave beam and a cross beam or two beams, usually at a corner of a building. With the two timbers it forms a triangle in plan, which keeps the rectangular frame from racking into a rhombus. Its purpose is to stiffen the horizontal plane of the building as seen from above, and it is also called simply hiuchi.

A member of the same kind placed at sill level in the floor frame is called a hiuchi-dodai. The hiuchibari is the one placed at beam level, in the corners of the roof frame or of an upper floor.

Two other diagonal braces are worth distinguishing. A sujikai runs diagonally within the plane of a wall between a post and a horizontal member, keeping the wall from racking. A hōzue is set in the angle between a post and a beam and props the beam from below. The hiuchibari differs from both in joining horizontal members within a horizontal plane.

Reading the records and the building

Records mention it in describing the frame, noting that hiuchibari are fitted at the corners. The record for the retail shop of Gyokusendo Brewery describes posts at half-bay intervals with hiuchibari at the corners, and the record for the flour storehouse of the former Marunaka Yokonaka shop describes a Wagoya roof frame with hiuchibari at its corners. Both are modern commercial or storage buildings in which the member was used deliberately to brace the frame horizontally.

On site, look up into a roof space, or into a room without a ceiling, at a corner where an eave beam and a cross beam meet. A short member laid level across the corner is a hiuchibari. A diagonal rising from a post to a beam is a hōzue, and one set within a wall is a sujikai.