kōryō taiheizuka 虹梁大瓶束

A structural framework in the gable ends of a roof characterized by the use of bottle struts *taiheizuka 大瓶束, a structural technique which began to appear in about the 13th century in place of frog-leg struts *kaerumata 蟇股. The framework employs an arrangement of rainbow beams *kōryō 虹梁 supported at their ends by 3-on-1 bracket complexes *mitsudo tokyō 三斗斗きょう, the apex of which carry a bottle strut with a bearing block and bracket arm *tokyō 斗きょう which in turn carry the ridge, *munagi 棟木, end. This is the simplest arrangement. These structural elements are visible in the gable pediments and display a splendid decorative sensibility. If two rainbow beams are used, the upper one is shorter and supported at each end by a bottle strut and bracket complex. Another bottle strut with a bracket complex is added to the center of the upper rainbow beam to support the ridge end. The entire structure is then called nijūkōryō taiheizuka 二重虹梁大瓶束.