Chabohiba Hall is deeply rooted in the community of Saiwaicho neighbourhood in western Tokyo: it is conceived for concerts,exhibitions and any cultural activity involving the local society. The site had been for centuries a focal node for the neighborhood; before the recent real estate escalation, the property was much bigger and unparcelled. Thanks to its position and extension, on this land were held yearly celebrations, matsuri, when people gathered to dance and play folk music. Reinvigorating the historical relationship with its context, Chabohiba perpetuates the matsuri role of social connector by translating it into a thriving contemporary feast.
The clients, descendants of the family who originally hosted the matsuri, decided to restore the ancient use of the place and to open it again to the public.
At the centre of the lot, a majestic cypress -in Japanese Chabohiba- kept firm throughout the wild housing development: throughout the centuries, this tree has become a symbol for the district.
The project features three main functional units:
2_reception and visitors' facilities
3_administration, performers' facilities and technical volumes;
The design revolves around the powerful fulcrum of the site, the centennial cypress. The building is a series of interlocked spaces whose soft boundaries draft a courtyard around the tree.
The main access is on the southern side of the lot. Ramps and steps are conceived to shape a terrace before the entrance, above the street level; from here the path is meandrous, as if to craft an exciting climax from the carefully sized entry to the broad courtyard and its majestic cypress. The entrance lounge spills into a foyer that connects the garden with the performance hall (1). The longest wall between foyer and hall can be opened completely so that the concert hall soon becomes part of the garden.
The building is see-through, from the courtyard to the space where music is played and behind it, up to the opening on the back; this is a long and narrow rock garden, along with the Japanese tradition of karesansui, dry landscape: its stones were found on site prior to the construction process, then kept away during the works and eventually re-placed as part of Chabohiba Hall. Other objects too were collected from the previous house and relocated around the complex, such as the terracotta urn now laying in the water basin.
Service spaces are located at the solid corners of the building: visitors’ facilities (2) are on the right hand side of the entrance whereas artists and staff members use dedicated rooms adjacent to the performance hall (3). A secondary entrance connects the back and the parking lot with offices and foyer, so that audience’s flow and performers move along two different routes.
The envisioned layout grants full flexibility to the hall: movable furniture had been preferred over fixed seats and partitions so that Chabohiba can host different kind of performances and events.
THERMAL The spatial layout of the concert hall is such that the core, the auditorium, maintains a constant level of thermal comfort whereas the spaces around it act as protective layers.
In winter, when sun rays are low and hit wide portions of walls and floors, concrete elements work as sun-heated thermal masses by releasing in the evening the warmth stored by day. During the damp heatwaves of the Tokyoite summer, the water basin strategically placed on the western side of the lounge helps to cool down the foyer; Chabohiba’s meandrous floor plan enhances natural cross ventilation.
ACOUSTIC To ensure the finest quality of sound propagation, the performance room has been studied with a computer-aided simulation: it’s walls are cladded with ribbed sound-insulating panels which provide multiple bouncing planes for the acoustic waves; their pattern, spacing and density has been custom designed by Satoshi Okada Architects and Nagata Acoustics, the top firm in the sound - design international scene. The ribs varies in depth and thickness, thus helping the music reverberating homogeneously in a defined time lapse.
Because of the dense built environment surrounding Chabohiba Hall, particular attention was given to sound proof enclosures, in order to avoid noise leaks and to respect the neighbors: the auditorium itself is thoroughly insulated with dedicated layers within the cladding; moreover the conceived floor plan is such that the multiple walls surrounding the performance room would screen it and would break the sound traveling outwards.
ENERGY SAVING A solar powered well pumps up water for the basin in the courtyard, so that the water cycle is fully ensured by renewable energy. The building is see-through: sunlight filters in and bounces on the pale-concrete surfaces and on the ceilings, so that artificial lighting is needed only after the sunset. The auditorium is lit by a low and horizontal Japanese window,: direct light at eye level is therefore avoided and the brightness flows in evenly.
CONSTRUCTION Chabohiba Hall's shape bears very well the horizontal loads of an earthquake: despite the frequent shakes occurred since its opening, none of the bare concrete surfaces of the building reported a significant crack. Being a single storey volume, the complex transfers relatively little weight onto the foundations, thus saving money, material and resources; the flat roof consists of an offsite assembled lightweight steel package.
DAILY USE The building is completely barrier - free due to its system of ramps.
EMERGENCY In case of emergency the building can be quickly evacuated through the foyer and across the garden; each door frame and passage is wide enough to ensure a wheelchair to cycle through comfortably; in case of fire water can be pumped out of the basin whereas walls and enclosures respond to the Japanese regulation in matter of fire resistance (walls ≥ REI 120, frames ≈ REI 90).
Satoshi Okada architects pursues intensity as its core value. Its designs are conceived to stimulate sensual perception. Satoshi Okada architects Inc. was founded in Tokyo in 1995.
Founder and director: Satoshi Okada graduated at Waseda University, Tokyo and at the Graduate School of Architecture, Planning and Preservation of Columbia University, New York, in 1989; later on he conducted research as a visiting scholar under Kenneth Frampton’s mentorship. He is Associate Professor of Architectural Design and Theory at the Graduate School of Architecture, Chiba University, Japan, and is often teaching abroad as visiting professor (IUAV Venice, ETH Zurich etc.) His design and research achievements have been acknowledged internationally with the Grand-prix Dedalo Minosse 2005-2006 (IT), The Chicago Atheneum International Architecture Award 2010 (USA) among others.
Lisa Tomiyama: managing director;
Tatsuya Terada: design team;