What a bachizuka is
A bachizuka is a short strut that widens towards its foot, its outline likened to the plectrum used on a shamisen. It stands on a beam or tie beam and carries the ridge or another member above. The JAANUS dictionary lists it among struts named for their shape or position, alongside the taiheizuka and kentozuka.
It turns up in two places. One is the gable, where it stands at mid-span on a beam to carry the ridge beam. In the 1880 connecting corridor of Kenkun Shrine in Kyoto, a bachizuka at the middle of the beam carries the ridge through a boat-shaped bracket; the gable of the front gate of the Kokawa residence in Nara, from 1923, is framed with a bearing block and bracket on a bachizuka.
The other is between posts as an intercolumnar support. The great gate of Motoyamaji in Mitoyo, Kagawa Prefecture, from the late Edo period, uses frog-leg struts in the front bays and the central rear bay and bachizuka elsewhere, keeping the more elaborate strut for the most visible positions.
What to look for
Look up at the gable: a short strut on the beam that flares at the bottom is a bachizuka. A taiheizuka swells like a vase and usually has carved side boards; a kentozuka is slender with a bearing block on top.
On gates it often stands on the upper beam of a yakuimon. At the 17th-century sacred gate of Minase Shrine in Shimamoto, Osaka Prefecture, the lower beam carries the upper beam through a bearing block, and a long bachizuka on top carries the ridge through a block and bracket.
Use the term where the record does; strut shapes can be hard to read in photographs.
References
- JAANUS (Japanese Architecture and Art Net Users System): tsuka
- https://projects.mcah.columbia.edu/jaanus/record/tsuka
- Agency for Cultural Affairs, Database of National Cultural Properties: Kokawa Family Residence Front Gate
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00006926
- Agency for Cultural Affairs, Database of National Cultural Properties: Minase Shrine Sacred Gate and Earthen Wall
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00011160
- Agency for Cultural Affairs, Database of National Cultural Properties: Kenkun Shrine Connecting Corridor
- https://kunishitei.bunka.go.jp/heritage/detail/101/00007061
- Agency for Cultural Affairs, Database of National Cultural Properties: Motoyamaji Great Gate
- https://kunishitei.bunka.go.jp/bsys/maindetails/101/00010373
Last verified: 2026.10.04