Flexible Skin The “Bloom” installation near Los Angeles demonstrates how thermo bimetals could respond to heat to shade or ventilate a building.
DOSU Studio Architecture Flexible Skin The “Bloom” installation near Los Angeles demonstrates how thermo bimetals could respond to heat to shade or ventilate a building.

By the end of this summer, Doris Kim Sung hopes to have ready a prototype of a glass panel system with metal shutters inside that open and close in response to their exposure to sunlight and heat.

For the past three years, Sung, an architect and associate professor with the University of Southern California’s (USC) school of architecture, has been working with thermo bimetal, a metal alloy made from manganese and nickel laminated together, which reacts automatically to changes in air and radiant temperature.

The metals in this alloy, which is commonly used for coils inside thermostats, expand at different rates depending on the temperature. At 70 degrees Fahrenheit, one of the metals starts to curl, and the curls tighten or flatten out as temperatures rise or cool. In essence, the metal can be seen as being both “active”—conductivity sets the metal into motion—and “passive”—and may be the ultimate in net-zero energy.

Sung believes that, ideally, architecture should adapt to human needs and not the other way around. “Why can’t buildings be more animated?” she asked during an interview that USC published in February. To prove her point, Sung’s team built a 20-foot installation at the Materials and Applications Gallery in Silver Lake, Calif., near Los Angeles. The exterior of this “Bloom” structure, as it is called, is made up of 14,000 6- and 12-inch pieces of thermo bimetal. Its purpose, she explains, is to demonstrate how thermo bimetals can act both as a sunshade as well as for ventilation.

Sung initially thought this material would have mostly commercial applications. For example, one of the grants she’s received is being used to reskin an Airstream trailer with this material, which would fan open on hot days. But she now believes thermo bimetal could also become part of passive residential systems.

The glass panel system she has been working on could serve as an automated shutter system without any need for motors or other drivers. (A manual device could be included to keep the cavity in the structure open.) When she spoke with Builder, Sung was trying to get the alloy to respond more to the sun’s penetration.

The cost of using thermo bimetals in architectural design still needs to be determined, too. Sung estimates the raw materials run about $100 for a 4x8-foot sheet. But she’s also convinced that the costs would come down as a result of mass production and making the materials even thinner.

Learn more about markets featured in this article: Los Angeles, CA.