yane kōzō 屋根構造

Keywords
Architecture
General Terms

The construction of the roof framework or roof truss over the body of a building. The essential framing for a gable roof *kirizuma yane 切妻屋根 is composed of purlins *keta 桁 and transverse beams *hari 梁. In traditional architecture, purlins run the length of a building and transverse beams run crosswise and diminish in length as the framework is built up on struts *tsuka 束 toward the peak. The ridge *munagi 棟木 is positioned along the peak, and rafters *taruki 垂木 are placed from the ridge to the eave ends *nokisaki 軒先. Sheathing *noji-ita 野地板 is attached to the rafters and then roofing is laid. If the roof is hipped *yosemune yane 寄棟屋根, corner or descending ridges *sumi kudarimune 隅降棟, are necessary. If the roof is hip-and-gable *irimoya yane 入母屋屋根, the upper part is constructed like a gable roof while the lower part is constructed like a cut-off hipped roof. Corner ridges are necessary and rafters have two lengths, from ridge to end of the gable part, and others that vary in size with the changing pitch of the roof. Bargeboards *hafu 破風 cover the rafter ends in the gable part.

a) *munagi 棟木 b) *moya 母屋 c) *taruki 垂木 d) ketayuki sujikai 桁行筋違
e) koyasujikai 小屋筋違 f) koyazuka 小屋束 g) *tsumabari 妻梁 h) *hiuchibari 火打梁
i) *koyabari 小屋梁 j) *gagyō 丸桁 (nokigeta 軒桁)