University of Southern California (USC)

University of Southern California (USC)

Los Angeles, CA


USC Architect First to Use Zero-Energy Building Material That Reacts Smartly to Sunlight

By Archinect
Feb 9, '12 4:27 PM EST

In architect Doris Kim Sung’s ideal future, buildings will automatically respond to changes in the environment.

“For a long time, my work has examined why architecture is static and nonresponsive, and why it can’t be more flexible like clothing,” said Sung, assistant professor of architecture at the USC School of Architecture. “Why do we have to adapt to architecture rather than architecture responding to us? Why can’t buildings be animated?”

At first, Sung explored mechanical building movement, like sliding walls and levered floors. Then, she hit upon a material that had never before been used in architecture: a metal alloy that responds automatically to changes in air temperature and heat.

“When I first got a sample of thermobimetal from the manufacturer, I felt like a kid. I just had to go outside and put it in the sun and watch it curl over and over,” Sung said. “I could not believe there was no energy required.”

Commonly used for the coil in a thermostat, “thermobimetal” is made of two sheets of metal laminated together. Each metal expands at a different rate when heated, curling as the temperature rises and flattening when cooled.

But the possibilities for buildings are even broader, especially since thermobimetal is not just completely zero-energy but actually reacts to changing environmental conditions. Imagine a canopy that curls shut when the sun is directly overhead, or a vent that opens automatically to let out hot air when it gets a bit stuffy inside.

With “Bloom,” a 20-foot tall undulating installation in Silver Lake, Los Angeles, Sung has made these ideas a reality. She’s received multiple grants to further her research with thermobimetal, including one to reskin an Airstream trailer in this dynamic smart material, so it can fan open and air out on particularly hot days.

“This would not have been possible a few years ago. We didn’t have the technology to cost effectively cut thermobimetal so that no two pieces are alike, and we didn’t have the software to tessellate complex surfaces into pieces that can be fabricated,” Sung said.

Thermobimetal is only available in 6-inch or 12-inch wide sheets, so the large “Bloom” structure had to be made of 14,000 small pieces, each one completely unique.

Sung is now working on ways to integrate thermobimetal with standard building components. Most conventional construction projects are still built in the method of stackable systems, so Sung is developing a glass panel that sandwiches a layer of thermobimetal and, like a shutter, automatically prevents the sun from penetrating the building by curling when heated. She’s also working on bricks with tiny thermobimetal vents to let the breeze through, inspired by biological systems like insect spiracle and trachea systems.

“We have to rethink the way we build, and what we build with. If we don’t, our problems will only get worse,” Sung said. “Being a researcher in smart materials and architecture right now is tremendously exciting. This is the time we’re going to change our future.”

“Bloom” was built in collaboration with consultant Ingalill Wahlroos-Ritter and structural engineer Matthew Melnyk, and is installed at Materials & Applications Gallery in Los Angeles through Spring 2012.