Although urban development often seems like a zero-sum game, the efficiencies of high density and the fragile beauty of nature need not be mutually exclusive. Tokyo has long been a locus of high-rise housing experiments, where Japanese architects have addressed the lack of space by creating some truly extraordinary houses. Indeed, Tokyo’s citizens remain steadfast in their appreciation of public green space; case in point, the vociferous protests against Zaha Hadid’s proposed olympic stadium in the gardens of Meiji Shrine, one of the city’s most revered parks.
Seemingly at total odds with one another, these inner-city conditions raise a pertinent question for architects: can high-density development and natural amenities be combined to the benefit of both? Japanese firm Kengo Kuma and Associates have attempted to answer this question with their latest Tokyo landmark, the Toshima Ward Office, a civic facility and residential tower to the north of the city center.
All images courtesy © Kawasumi・Kobayashi Kenji Photograph Office.
The one-million-square-foot mixed-use building is comprised of two primary volumes, with council offices housed in the trapezoidal lower half and apartments in a vertical tower above. Its tapered base and slender upper section reflects the firm’s metaphorical concept for the building: Kuma designed the complex as a giant tree, aiming to create a structure that functions as a truly natural organism within Tokyo’s manmade forest of concrete, steel, and glass.
The building’s simple overriding form belies its complexity, which is revealed upon closer examination of each tapered façade. Kuma employed a tripartite system of cladding panels or “leaves,” each one linking back to the core concept of utilizing the natural qualities of trees: the architects call this the “Eco Veil,” a permeable curtain made up of three vital components that play different roles in regulating the building.
Firstly, recycled timber louvers provide shading and ventilation to the interior spaces. Secondly, photovoltaic panels are incorporated to collect and store a healthy portion of sustainable energy for use in the municipal office spaces. Finally — and perhaps most significantly — vegetated “green wall” panels will, in time, transform the exterior into a checkered quilt of plants to accompany the warm timber and gleaming solar surfaces. These rectangular frames of wire mesh are sparsely hung with greenery at present, but should soon burst into life with the arrival of Tokyo’s intense summer sunshine.
The feature that brings this vast complex closer to nature than any other though is its vertical garden, which wraps around the outside of the office spaces and will act as an urban oasis — not just for staff and residences within the building, but also for the wider public, who have free access to the planted terraces and open-air park on the 10th floor. Shaded by those recycled timber louvers, the covered walkways are lined with continuous borders of native species, with wooden decking alongside to facilitate the tending of the plants.
The building’s interior is substantially more conventional in its layout and material finishes, with a soaring glass-roofed atrium allowing natural light to filter through to the heart of the expansive lower volume. Its exposed steel structure and mechanical elements express a modern, constructivist aesthetic akin to the atrium of Richard Roger’s Lloyds Bank in London, but Kuma’s attachment to natural patinas sets this building apart, with further recycled timber members adorning the elevator shafts and emphasizing the verticality of the space.
Having just been completed, this building does not appear, on first impression, to differ hugely from the many high-tech high-rise towers sprouting across the planet; rather, it reads as a contemporary skyscraper wrapped with a quirky patchwork quilt of cladding panels. However, given time, the external terraces of the structure should evolve and grow into a riot of shrubs, plants, and flowers — within a few months, the vertical garden will begin to emerge.
With the Toshima Ward Office, Kengo Kuma may just have produced the closest marriage yet between high-density urban architecture and green amenity spaces — and the best part of all is that it will be accessible to all.