By Martin Søberg
Structured and translucent, like a Japanese paper lantern. Shibaura House by Kazuyo Sejima & Associates brightens up the Shibaura district in Minato-ku, Tokyo’s pulsating business area near the Tokyo Bay. Public and private programs interweave in this cunning, white-clad amalgamation of boxy geometric volumes and playful curves.
At first glance, Shibaura House appears as a tall, rectangular, white box. A closer look reveals three large terraces of different sizes and footprints, masked by stretch metal mesh. These volumes seem to be cut into the orderly outer structure. Diagonal beams keep the construction in place and form enormous, slightly puzzling K’s in a façade divided into a shifting pattern of rectangles. Glass panes screen the rest of the building, resulting in the reflecting semi-transparency of the exterior.
The rectangular outer contour disguises the fact that the building consists of a pile of concrete decks of various shapes. A section of the house demonstrates its spatial diversity, attested to by the varying ceiling heights. Each level seems to overlap the next, causing a sensation of flow between the floors. Curving staircases coyly emphasize this feeling.
Shibaura House is run by Kohkoku Seihan Inc., which rents out most of the spaces to nonprofit organizations, schools, and individuals to be used for exhibitions, workshops, seminars, and parties. It functions almost like a community center during evenings and weekends.
The south-facing double-high first floor space is publically accessible from the street. It contains tables for working or reading and a coffee station. Plenty of lush green plants provide for a homely atmosphere. The second and third floors are lounge areas appropriable for various purposes such as meetings and cultural events and with access to two terraces. Rounded glass walls divide the spaces into smaller sections. Offices are on the fourth floor, while the corner ‘Bird Room’ on the fifth floor has a commanding view of the surrounding neighborhood. Its 90m2 have no partition walls in order to secure maximum functional flexibility.
The spatial and programmatic elasticity of the house reflects a certain attitude towards the creation of public and semi-public spaces: the possibility and necessity of bringing peoples physically together. As Kazuyo Sejima has stated,
The twenty-first century has begun and many things have changed; people, cultures and economies have never been so connected as they are today. Due to advances in technology, we have started to connect with other people in a completely different way, forming relationships indirectly as through the internet. In this new intangible world I believe that architecture occupies a unique and important place.
Challenging the nine-square grid
Shibaura House is framed and structured by ten loadbearing posts around the façades, resulting in a square 14x14m footprint dividable into nine equal squares. Hence the building may be interpreted as a response to the famous nine-square grid exercise: This exercise was invented by architect John Hejduk in the 1950s and subsequently used at schools of architecture worldwide. The question is how to spatially divide a square, subdivided into nine smaller squares? Sejima offers seven elegant solutions: Curvaceous, yet simple.
Layering these plans results in architecture full of movement and counter-movement. The asymmetry of these free-plan spaces may refer to Japanese wabi-sabi aesthetics, but as well to European modernism, without the material extravaganza of say, a Mies van der Rohe. The most luxurious thing about Shibaura House is the spaciousness of its rooms in a city notorious for its exorbitant land prices. This is architecture far more down to earth, stripped down and pragmatic, yet with a playfulness instigated by the rounded shapes and shifting heights of its interior and semi-interior spaces.
Sejima’s sense of structure
Transparency, curves, boxes, and white paint: recognizable features of architecture by Kazuyo Sejima and not least SANAA, the office she runs with Ryue Nishizawa. Her Carina Shop building in Tokyo (2009) shows a similar use of white metal mesh, completely changing the impression of the building between day and night, from solid to transparent. All elements assembled with a clear sense of structure.
Like Shibaura House, SANAA’s New Museum (2007) in New York City is also a small tower of stacked boxes. Yet while the Museum appears somewhat introvert – the obvious reason for this is the need of wall space for exhibitions purposes – Shibaura House it outright extrovert, inviting people to see and meet other people and to engage in common activities.