Prefabrication experiments - 123 - material innovations – 4 – Thin shell fibre-reinforced concrete spheres

Government sponsored housing experiments, test sites or laboratories fostered numerous twentieth century prototypes and in some ways reinforced modern architectural theory. The required improvement of urban infrastructure commanded by industrialization or essential post war regeneration compelled politicians to underwrite significant public works and social housing schemes secured by elaborate delivery and construction methods.

The Chamberlain Housing Act (1923-UK), Operation Breakthrough (1969-USA) The GSK (school construction system) Project (1983-Japan) promulgated social, political, economic and technical agendas. Housing and education benefited from similar programs in virtually every industrialized nation. Progressive urban renewal programs such as the experimental housing subsidy accorded from 1968 - 1984 in the Netherlands continued the tradition of government-subsidized investigation.  Architects and industrial development gained from the opportunity to envision future potentials for housing systems and their materialization. 

The Bolwoningen neighbourhood in the small Dutch town of Den Bosch is a noteworthy case for innovation through housing trials and laboratories. Designed by artist/sculptor Dries Kreijkamp, the standing juxtaposition of a cylinder for circulation and a sphere for dwelling constitute the individualized households sprinkled in a flat grassy meadow. The original proposal explored glass fibre reinforced plastic, however the required fire resistance made concrete the concession material for the «bulbs».  The case for concrete, glass-fibre reinforced concrete in particular, achieved the required flexibility to cast perfectly cylindrical and spherical shapes while presenting structural integrity, durability and fire resistance. 

Each dwelling consists of two factory cast concrete hemispheres, delivered and anchored to an on-site cast cylinder foundation, which housed the doorway, storage and a spiral stair. The 1500 kg spheres were assembled in a day, and the spherical shape embodied the ideal of maximum space within a minimal volume. Inspired by traditional clay roundhouses and arctic igloos, the bubble represented the simplest form of human shelter. The 55m2 dwelling space seemed to offer an ideal setting for individuals or couples. The thin shell concrete bubbles were pierced with round windows, which further signified the proposal’s distinction. Each bulb was a simplified component of a new industrialized system for housing and could eventually be complemented by floating rooms or bridges repositioning the scheme from a uniquely individualized proposition to an aggregation of collective clusters.

Bulbs' cross section and site photograph