Konkuri-an is a 12.46-square-meter reinforced-concrete teahouse in a narrow Kamakura valley. Designed by Teitakusubako + YIA, it recasts the spatial discipline of the Japanese Soan teahouse through exposed concrete, reinforcing steel, timber, and a carefully staged garden approach.
Konkuri-an Technical Information
- ArchitectsTeitakusubako + YIA
- LocationKamakura, Japan
- Gross Area12.46 m2 | 134 Sq. Ft.
- Project Year2022
- Photographs© Kentaro Nemoto, © Kazumasa Harada
The intention is not to reproduce historical materials, but to retain the relationship between texture, scale, light, and bodily experience that defines the Soan.
– Teitakusubako + YIA
Concrete as Site Response and Architectural Premise
Konkuri-an occupies a narrow valley in Kamakura, where a steep planted slope rises immediately beside the building. Because the site falls within a designated landslide warning zone, reinforced concrete was required to respond structurally to the unstable terrain. Rather than disguising that obligation, the project makes the concrete shell the basis for its architectural language. The resulting enclosure is compact, thick-walled, and materially direct, with a small footprint calibrated to the site’s constrained conditions.
The building sits against a retained slope of dry-laid rounded stones, dense vegetation, moss, and exposed earth. This garden terrain prevents the concrete from reading as an isolated object. Its board-marked surfaces receive reflected green light from the foliage, while the rough stone retaining wall establishes a second, slower register of mass and weathering. The teahouse thus occupies a threshold between engineered protection and cultivated landscape, with each condition made visible rather than merged into a seamless image.
A thin concrete roof slab projects substantially beyond the enclosing walls. Its cantilever creates a sheltered edge along the roji, extending the building’s protective role into the approach sequence. Beneath this overhang, the visitor moves between moss, stepping stones, and the vertically textured concrete facade before entering the compressed interior. The roof is not simply an expressive horizontal gesture: it establishes an intermediate zone where the climatic and geotechnical realities of the valley become part of the tea ritual’s measured progression.
Reconstructing the Soan Through Material Substitution
The project does not treat the Soan as a fixed catalog of earthen plaster, bamboo, cedar, and paper. Instead, it asks which material properties and constructional effects sustain the typology’s spatial character. Concrete replaces earthen wall construction, reinforcing bars assume the filtering role of bamboo lattice, and agathis replaces the cedar typically associated with tea room joinery. These substitutions retain neither historical appearance nor craft technique in a literal sense, but they preserve distinctions of texture, scale, weight, and permeability.
High-pressure washing gives the upper concrete surfaces an exposed aggregate finish. In the tea room, this coarse and irregular surface recalls the particulate character of tsuchi-kabe, or earthen plaster, without concealing its concrete origin. Below it, a smoother band cast against lauan plywood establishes a wainscot-like datum around the room. The timber grain and panel joints remain embedded in the concrete, reducing the apparent scale of the monolithic structure and introducing a precise transition between the room’s rough upper field and its more controlled lower zone.
The shitaji-mado offers the clearest instance of this translation. Where a conventional detail might use bamboo lattice behind a plastered wall, Konkuri-an exposes vertical reinforcing bars within the opening. The bars register the structural logic of reinforced concrete while producing a screen of fine, repeated elements. Their depth, shadow, and partial opacity maintain the visual filtering associated with the traditional window, yet the detail avoids nostalgia. It makes the construction system legible at the exact point where the tea room mediates between its heavy enclosure and the garden beyond.
Spatial Discipline Within the Three-Mat Tea Room
The interior follows the compact order of a three-mat tea room. Tatami establishes the floor geometry, while the hearth, tokonoma, guest entrance, host access, and adjoining mizuya are arranged according to the operational requirements of tea practice. This organization makes the small room highly specific rather than merely minimal. Each opening, alcove, and circulation point has a defined ritual role, directing the relationship between host and guest without excessive visual elaboration.
Concrete gives the room an unusually cave-like darkness, but a sequence of carefully placed apertures moderates its weight. A long shitaji-mado, a high square opening, shoji screens, and a deep-set view toward a concrete light court admit different degrees of daylight. The low nijiriguchi frames volcanic rocks, moss, and grasses at floor level, turning entry into a focused encounter with the garden. Rather than offering panoramic exposure, the openings fragment the exterior into measured visual events.
Finer-grained elements counter the concrete shell’s apparent permanence. A pale timber-lined ceiling slopes over the host’s position, recalling the differentiated ceiling planes of traditional tea rooms. A natural timber post marks the tokonoma, its slight irregularity contrasting with the cast precision of the surrounding walls. Paper-faced fusuma doors, timber window ledges, and slatted screens introduce further tactile variation. These elements do not soften the concrete through decoration; they establish a surface hierarchy that lets the room register bodily scale.
Garden Sequence, Thresholds, and Contemporary Continuity
The roji functions as a spatial instrument rather than a landscape backdrop. Stepping stones curve through moss and low planting toward the tsukubai, where the water basin marks a preparatory pause before entry. A long rough-hewn stone bench forms the machiai against the concrete wall, offering a waiting position beneath the extended roof. A low bamboo rail interrupts the route, while a gate wall at the garden edge establishes another degree of separation between the surrounding valley and the tea house sequence.
Material contrasts are deliberately sustained throughout this movement. The damp softness of moss meets the roughness of volcanic stone; board-marked concrete runs alongside dark steel bars; timber shutters and screens sit within deep openings in the structural wall. None of these materials is asked to imitate another. Their juxtaposition produces a controlled friction that gives the garden and building distinct roles. Stone retains its geological weight, vegetation its seasonal variability, concrete its structural mass, and steel its linear precision.
In this sense, Konkuri-an treats typological continuity as an issue of spatial conduct rather than historical reproduction. The Soan remains legible through compression, low light, asymmetrical views, material restraint, and the choreographed movement from garden to crawl-in entrance. Its contemporary character lies not in abandoning those conditions, but in allowing reinforced concrete and exposed steel to carry them forward on their own terms.
About Teitakusubako + YIA
Teitakusubako + YIA designed Konkuri-an, a contemporary teahouse in Kamakura, Japan. The project reinterprets the spatial qualities of the Japanese Soan through contemporary materials and construction methods, using reinforced concrete, exposed reinforcing bars, timber, and carefully controlled relationships between texture, scale, light, and bodily experience.
Credits and Additional Notes
- Structural engineers: Masaki Sugimoto Structural Office
- Construction company: Daido Kogyo
- Other contributors: Photography by Kentaro Nemoto and Kazumasa Harada
