top of page
  • john barr

Do|Co|Mo|Mo|Japan|22 : Chiba Prefectural Central Library : Masato Otaka


Do|Co|Mo|Mo is an international organisation dedicated to the Documentation and Conservation of buildings, sites and neighbourhoods of the Modern Movement. The Japanese branch has selected 100 works as representative of the development of the Modern Movement in Japan. In a series of short posts I will feature some of the selected works that I have had the chance to visit and photograph. This post features the Chiba Prefectural Central Library located in Chiba City, completed in 1968 and designed by Masato Otaka...


Background

Otaka was one of the Metabolist group featured in my post dated 29 June 2018 but, along with Fumihiko Maki, had never been fully committed to the planning strategies pursued by the rest of the group. Where much of Metabolism revolved around ideas of top-down masterplanning, achieved through the development of mega-scale superstructures that could expand across entire cities, Otaka and Maki were interested in a bottom-up, slow accretion of urban form. Together they had been developing ideas for what they called Group Form, with Otaka looking at repeatable forms that could cluster and Maki studying the traditional collective forms that had evolved incrementally in Mediterranean communities. These two approaches became apparent in their later works, such as Maki’s designs for Hillside Terrace in Tokyo, a collection of buildings for one client, completed in stages over a period stretching from 1969 – 1992, and a series of designs by Otaka based on use of a repetitive structural module. That interest was to lead Otaka into prefabrication, and Chiba Prefectural Library is an example of his merging of these two strands: a repetitive, prefabricated structural module.


Hillside Terrace, Tokyo, Fumihiko Maki. Completed in six phases (1966-1992)

An example of Group Form: 'Neutral Buildings used in the Formation of Place.' Fumihiko Maki


Design

Columns that are cruciform in section are connected via cruciform capitals to an open-ended grid of precast, prestressed beams. All elements are prefabricated. The square grid forms the basic planning unit and is used to create spaces of different scales in a relaxed, free-flowing plan that can grow incrementally in all directions. The kit of prefabricated parts is deliberately exposed to reveal how the structure has been assembled.


Chiba Prefectural Central Library, Masato Otaka, 1968.

Cruciform columns with cruciform capitals sit within a grid of precast beams.


Chiba Prefectural Central Library, Masato Otaka, 1968.

The grid module and changes in height are used to create spaces of different scale and intimacy.


Chiba Prefectural Central Library, Masato Otaka, 1968.


Chiba Prefectural Central Library, Masato Otaka, 1968.

The kit of parts is left exposed to reveal how the structure is put together.


Significance

This is the first time that precast, prestressed concrete elements had been used in this way in Japan. It appears to be a further development on prefabricated systems that had appeared in Italy in the 1960s, such as Angelo Mangiarotti’s Birra Poretti warehouse design in Mestre, and also similar to the refined structures being produced by Arup Associates in the U.K.


Chiba Prefectural Central Library, Masato Otaka, 1968.

Approach to main entrance.


Chiba Prefectural Central Library, Masato Otaka, 1968.

Reading area,



All images by John Barr unless otherwise noted

© John Barr 2021


bottom of page