schemata architects completes bold renovation of old public bathhouse in tokyo

schemata architects has completed the renovation of pre-existing ‘koganeyu’ communal bathhouse in tokyo. sento, or japanese public bathhouses have been a longtime favorite gathering place for the regional community. however, now that 95% of households in japan own private bathrooms, many sento have been forced to close due to a shrinking customer base. taking this into account, the architects have decided to help ‘koganeyu’ venture into a new era, with a bold refreshing redesign. 

all images by yurika kono

aiming to maintain koganeyu’s role in connecting people, schemata architects decided to preserve the old size of the bath areas, while transforming the remaining space into a gathering place for the younger customers. in other words, the previously unused space that was limited to housing the boiler room, storage, and the machine room, now features newly added functions such as a beer bar, a sauna, and an air bath.

the interior features a partition wall, separating men and women’s bath areas, which does not reach the ceiling and leaves an opening at the top. this is actually one of the most common characteristics one can observe within sento, all over japan. although a full-height wall would be more stable and easier to construct, the specific design facilitates communication for families who visit the bathhouse together. ‘male and female members can easily call out to each other to check if they are ready to get out, or perhaps they want to feel each other’s presence on the other side of the wall – it’s hard to say’ schemata architects shares. 

the wall height line was decided to be placed at 2250mm above floor level, and it has been used as a reference axis for the design materiality. specifically, components below the 2250mm line all showcase a light beige color, to represent the human body. meanwhile, elements above the 2250mm line are made of concrete, along with other cool-toned materials, that harmonize with the exposed structural frames.

schemata architects has asked artist yoriko hoshi to paint a mural of mount fuji, spanning over the entire width of both bath areas; another traditional element of japanese sento. the art piece features various scenes of a story transcending boundaries between males and females, set against a backdrop of mount fuji, in the style of a picture scroll.

in addition, artist iichiro tanaka was asked to design noren (split curtain) to be installed in men’s and women’s changing rooms. the artist has been inspired by the expression ‘oi!’ (hey!), which has been exchanged between men and women over the separating wall for years. using this saying, he wanted to convey the feeling of ‘sending one’s heart to someone on the other side of the wall’. furthermore, a long handrail was included within the room, going over the wall from one side to the other, so that men and women, while they cannot see each other, can hold on to the same handrail to feel connected.

the wall disappears at the bandai (reception counter) area, where the top of the light beige area is lowered from 2250mm to 1150mm above floor level, to align with the countertop. here, a beer bar is installed as a place for men and women to enjoy good conversations under the glass lantern. the soft glow will illuminate customers’ little luxury moments and enhance warm-hearted connections within the community.

project info: 

name: koganeyu
architecture office: jo nagasaka / schemata architects
project team: kotaro shimada
creative direction/graphic design: TAKAHASHIHIROKO
structural consulting: ladderup architects
in collaboration with: yoriko hoshi (mural of mount fuji), iichiro tanaka (noren), hoshizaki (kitchen), whitelight (sound plan), aqua planning (advisor)
location: 4-14-6 taihei, sumida-ku, tokyo
total floor area: 1113.34 m2