Material for an Architectural Revolution

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No Sharp Objects

But the ETFE system also cost less (though they wouldn't give specifics) than an equivalent traditional system, freeing up money for higher-quality filtration and water-treatment systems for the center's pools. A more traditional form of cladding would have been not only more expensive and cumbersome, says Bilmon, it would have resulted in a "…less exciting, beautiful, and functional building."

The material's appeal is manifold, and those who work with it praise its unique properties. First, it's extremely light—about 1/100 the weight of glass—and deceptively strong, able to stretch to three times its length without losing its elasticity. (Having said that, a sharp implement like a knife can puncture it—one reason it's used mostly for roofs.)

If the film does tear, it can be patched with other pieces of ETFE. When exposed to fire, it softens and shrinks away from the heat, naturally venting smoke out of a building. And it's naturally nonstick, nonporous surface, which has chemical properties similar to DuPont's other best-selling material, Teflon, is so slick that dirt, snow, and rain simply slide off.

Shape Shifter

Its light weight reduces corresponding structural costs. Edward Peck, managing director of the North American Division of Foiltec, which now has 12 offices and 250 employees worldwide, estimates that a simple, small roofing project could be 10% cheaper if ETFE were used. For larger, more complicated projects, the overall construction savings could reach 60%.

Then there's the fun factor. ETFE comes in different finishes (transparent, matte) and colors, and can be lit from within using LED lights or decorated with light projections like a giant movie screen. It can be printed with patterns by running it through a special press—something not possible with glass. It can take myriad shapes, too: Strips can be heat-welded together like fabric squares in a quilt. This "sewing" method enables ETFE to be installed in pieces much longer and wider than glass. A large glass panel might measure 10 ft. by 5 ft., whereas a strip of ETFE could be 180 feet long and 12 feet wide, with structural supports.

It also scores well on the environmentally friendly front, particularly crucial given the current call for greener building practices. The film is recyclable (simply melt and reuse), and due to its light weight, doesn't require much energy to transport. The Watercube is designed to gather heat passing through its ETFE walls and roof—energy that can be used to heat the building's water systems or expelled through vents if the building gets too hot.

High Maintenance

On an aesthetic level, the cushions reinforce the building's theme. Their pillowy shapes evoke a bubbles's roundness, and their triple-layered construction, which mixes layers of blue film with transparent film, gives the façade a sense of depth and shifting color. Once the games start in August, 2008, officials will be able to transform the walls into a giant TV screen showing simultaneous projections of the swimming activities taking place inside.

For all its wondrous properties, ETFE isn't an entirely perfect material. In its typical usage, two or three layers are welded together and shipped flat to the job site, where they're inflated into panels or "cushions". These cushions require semi-continuous air pressure—to keep them stable and give them thermal properties—so most systems include thin hoses that plug into the cushions' sides.

These air-supply lines connect to a computerized system that monitors the pressure within the cushions. This system can also feed air into, or eject air from, particular chambers or layers to let in more light or create more shade, meaning the ETFE cushions act as a dynamic puffer jacket for buildings. In some installations, this is done automatically using light sensors.

Overheard Overhead

Of course, many projects don't call for such complexity.