What a tsuchido is

A tsuchido is a heavy door built up from earth over a timber core and finished in Shikkui. Far less combustible than a boarded door, it is hung at the doorways of buildings in Dozo-zukuri and at castle gates.

Storehouses use them at doors and windows alike. The Takagi Residence storehouse in Aichi Prefecture, from the early Taisho period, is described as finished in white plaster with Namako-kabe at the base, a doorway on the west gable under a tiled hood hung with black-plastered double doors of this kind, and a single-leaf plastered door at the upper window under its own tiled hood.

The Sanjido Sasaki storehouse in Miyagi Prefecture, from the middle Taisho period, has plastered double doors hung to the shop interior at the centre of its south face. The Sairenji storehouse in Aichi Prefecture, from the Meiji period, has similar doors set beneath a hood.

Black plaster appears because it hides soiling and contrasts with the white above, which makes it a design choice as well as a practical one.

At castle gates

Castles use them for the same reason. The iron-banded gate at Matsuyama Castle in Ehime Prefecture, reconstructed in 1967, has an upper level used as a bridge corridor with double doors of this kind at each end, and the inner gate is built the same way.

The corridor turret at the same castle has them at the doorway above the stair from the small keep. Placed at the junctions between the buildings of the Tenshu group, they keep a fire in one building from reaching the next.

They are usually paired with a hood over the Tomae. The door is heavy and vulnerable to rain, so a small roof protects it, which is what the Takagi entry describes.

On site, look at the thickness of the door and the profile of its edge. A door plainly thicker than a boarded one, with the edge built up in steps, is this type. The stepped finish closes the gap when the door is shut.

References

Agency for Cultural Affairs: Registered tangible cultural properties (structures)
https://www.bunka.go.jp/seisaku/bunkazai/shokai/yukei_kenzobutsu/toroku_yukei.html
National Cultural Properties Database: Takagi Residence storehouse, hung with black-plastered doors and a single-leaf door above
https://kunishitei.bunka.go.jp/bsys/maindetails/101/00004246
National Cultural Properties Database: Sanjido Sasaki storehouse, plastered double doors hung to the shop interior
https://kunishitei.bunka.go.jp/bsys/maindetails/101/00005220
National Cultural Properties Database: Sairenji storehouse, plastered double doors set beneath a hood
https://kunishitei.bunka.go.jp/bsys/maindetails/101/00006609
National Cultural Properties Database: Matsuyama Castle iron-banded gate, a turret gate forming the southern square enclosure
https://kunishitei.bunka.go.jp/bsys/maindetails/101/00013001
National Cultural Properties Database: Matsuyama Castle corridor turret, linking the small keep to the south corner turret
https://kunishitei.bunka.go.jp/bsys/maindetails/101/00013000

Last verified: 2026.09.03