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More dramatically, the design reclaims formerly "dead" courtyard space and exploits the potential of the existing building. It stretches a new roof over the now-interior courtyard, offering new dining facilities, assembly/ performance space, improved circulation, and space for social activities.

De Rijke reports that there was little resistance to the radical design. Only the government's education department challenged the size of the space (34,000 square feet, or 3200 square meters) out of concern for the cost of heating such a large volume.

However, de Rijke explains, temperature under the new roof is passively controlled. "It is a temperate space, similar to a train station, so it can accommodate multiple activities and is an economical to maintain and heat." Because the space is so large, other structures can be built within it, so this is not a "final solution."

The New Roof

The architects considered many options for the roof materials and finally chose an ultra-violet-stable fluoropolymer, ethylene tetrafluoroethylene (ETFE), welded into cushions. This material requires the least support structure and maximizes daylight in winter.

The cushions are restrained around their perimeter by a frame of extruded aluminum, which is in turn fastened to a supporting primary structure. The roof structure is supported by the existing building, around the perimeter of the courtyard. This gives an open space below, unencumbered by supporting columns.

The cushions are inflated with low-pressure air to provide insulation and to resist wind loads, a system similar to the one used at the Eden Project.

Unlike the Eden roof, however, Kingsdale's roof has a "variable skin." The ETFE cushion's multilayered construction creates climatic envelopes that change insulation and solar transmission levels depending on climatic conditions. These changes affect the visual appearance of the envelope and the amount of solar heat gain penetrating the building.

At 260 by 130 feet (80 by 40 meters), this roof is thought to be the largest of its kind in the world. The system was adapted by dRMM with a screen-printed pattern on two of the three layers of the membrane, providing the daylight control mechanism. When the roof cushions are fully inflated, the printed layers let in 50 percent of available daylight. When the layers are deflated, the daylight penetration can be reduced to five percent.

The Dome Below

Despite the spectacular roof, it is the domed, 314-seat auditorium and library that grabs one's attention in the courtyard. Standing just off center, the pod is a geodesic wood structure. Birch members are connected via lightweight aluminum nodes and covered in plywood. Suspended from its roof is an Atelier van Lieshout's "cannon" that provides electric lighting, air and sound.

The rest of the interior courtyard has been carpeted, encased in glass walls, and is used as a library. High-level walkways on the first floor are wide terraces for some classrooms to open directly onto. This first floor circulation offers a spectacular view of the new infrastructure.

Sharon Wright, managing director of School Works, reports the project is already providing positive results. "There are clustered flexible spaces for interactive group working that resemble and prepare students for the high-tech workplace. There will be access for the local community to a new auditorium and library. And the school is thriving. This year, Kingsdale was also named as one of England's top 20 most improved secondary schools."

Harder to measure but equally powerful, she notes, are the effects that a professional working space has on staff morale and that a beautiful school has on student motivation for learning.

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Don Barker is a freelance writer and photographer in London, who has lived and worked in Europe, Australia, Thailand, Sri Lanka, Hong Kong, and Singapore. He is a contributing editor to ArchitectureWeek and writes for several periodicals in the United Kingdom.

A roofed courtyard and a geodesic auditorium have transformed Kingsdale School. Photo: Alex de Rijke Longitudinal section through Kingsdale School. Image: de Rijke Marsh Morgan Cross section. Image: de Rijke Marsh Morgan Geodesic frame for the auditorium. Image: Cowley Timber Work Inside the auditorium. Photo: Michael Mack Classroom and lobby, Kingsdale School. Photo: Alex de Rijke Ground floor plan, Kingsdale School. Image: de Rijke Marsh Morgan Top floor plan. Image: de Rijke Marsh Morgan   Click on thumbnail images to view full-size pictures.