Kengo Kuma’s wooden layers spiral the SANA MANE SAZAE sauna in Japan

Yayoi Kusama’s iconic yellow pumpkin on an island pier in the Seto Inland Sea is an image etched in every art lover's mind. Installed in 1994, this art installation became Naoshima’s identity, a region known for its contemporary art museums, architecture, and sculptures. A home to unique installations by famous contemporary artists, Naoshima has established itself as an important location on the art map of Japan. Interestingly, the architectural portfolio of the island also attracts attention. Whether it be Sou Fujimoto's Naoshima Pavilion, Tadao Ando’s Chichu Art Museum, Benesse House and Lee Ufan Museum or SANAA’s New Honmura port terminal building, the buildings of Naoshima translate architecture into large-scale immersive art. Bringing a new perspective to Japanese modern architecture is Kengo Kuma and Associates' sauna design for the resort facility, SANA MANE.

Situated near the beach of Naoshima, the resort is an organic structure bulged at the bottom, spiralling upwards to appear like an enlarged shell, placed upright on the shore. Following the principles of the Japanese architects' approach to design, the sauna design draws from its context, which sits in the coastal region, and has been inspired by a mollusk. The name of the sauna also takes after this inspiration and is called SAZAE, the Japanese name for the mollusk, Turbo cornutus.

On closer inspection, the sauna is structured in layers of wood. With a wall thickness of 450 mm, it is made by stacking 150 layers of 28 mm thick plywood that has been CNC machined. The shell-like fine folds created by multiple layers of wood that spiral up, creates interesting shadows. The only inlet of light in the structure is the oculus at the top which channels natural light in a dramatic yet meditative manner, lending a sacred character to the interiors.

The surfaces of the wooden layers expand into the interiors to become curvaceous seating and circulation spaces. “Although it was a complex shape using 1,500 plywood sheets, it was programmed using 3D CAD, so the design of the shape and the plywood panelling were controlled in tandem. Unlike a general sauna, the temperature and humidity are kept at an optimum level by making full use of environmental simulations and designing forced ventilation airflow, despite the high ceiling,” mention the architects. Resting amid the geodesic cottages of SANA MANE, the wooden structure, while functioning like a sauna, also shapeshifts into imparting a monument-like presence to the site—an extension of the island’s art character into the resort's hospitality architecture.

Kengo Kuma and Associates’ fascination with wood architecture has been seen over multiple projects, sometimes as facade elements, and at other times, as roof structures or in installations and pavilions. Whether it be spiralling, dynamic ribbons of wood in The Exchange in Sydney, the main role of timber in The HC Andersen Museum or the Botanical Pavilion at NGV Triennial 2020, their experimentations with the materiality of wood has been intriguing. However, most of these designs mostly extend to become linear or geometric. Therefore SANA MANE SAZAE sauna unwraps as a unique narrative from the architects, with the possibility for bigger innovations and larger structures in CNC machined wood masonry. In the artistic and architecturally rich culture of Naoshima, Kengo Kuma’s organic wooden sauna presents an innovative future for contemporary Japanese architecture.