Kalwall

Insulation Idea Jells
Manchester hotel installs aerogel, world's lightest solid

The Telegraph
Nashua & Region
January 15, 2003

DAVID BROOKS
Science From The Sidelines

How do you know when a rooftop installation is unusual? When management folks go up to watch.

"There were a lot of people with suits on the roof, watching them install the panels," said Fred Bailey, owner of the Comfort Inn in Manchester, chuckling.

Although this sounds like the title of a parody musical - "Suits on the Roof: A Fable of Dot.Com Life" - it actually makes sense.

The roughly 800-square foot covering, installed late last year over the hotel's swimming pool, is America's first everyday application of aerogel - the world's lightest solid, a weird, funky stuff that until now had only shown up in spacecraft, cryogenics and other cost-be-damned applications.

"My father was interested in aerogel since it was invented," said Bruce Keller, marketing vice president for Manchester-based Kalwall, which built the super-insulating panels in conjunction with chemical firm Cabot Corp. of Boston.

"We've been pursuing aerogels for years as part of our corporate mission ... We've used our own research guys, and in conjunction with labs - mostly entrepreneurial - and near the end worked with (German chemical giant) Hoechst and Cabot in a joint venture," he said.

Aerogel has been around for 70 years, and has been seriously studied for more than a decade in places such as the Jet Propulsion Laboratory, which uses it in a variety of spacecraft.

Basically, aerogel is a solid foam made of silicon, but due to an odd molecular structure, it is the ultimate puffball. Measuring 99.8 percent air by volume, 1/300th the density of water with a bluish tint, it has been called frozen smoke.

Aerogel's porosity makes it a fabulous insulator. Jet Propulsion Laboratory has a picture of wooden matches lying unconcerned on a sheet of aerogel, despite a blue-hot flame roaring underneath.

Kalwall sandwiches aerogel, made in a factory in Germany, between panes of glass to create panels that let in enough light to illuminate a room, yet insulate as well as a cinderblock wall.

They have an R-value - a standard term used to measure insulation - of about 20, which is five to 10 times the insulation value of a thermal pane window, and twice the value of the current translucent champion, a curtain wall system using mirror films and argon gas between multiple panes of glass.

At the Comfort Inn, nature has provided a perfect test.

"The snow on the outside of the roof is very slow to melt. We had a first-generation (Kalwall) roof before, and there's a dramatic difference," Bailey said.

Otherwise, there's nothing unusual about the roof, which looks very similar to its predecessor.

"People don't notice it - just that they're warm and comfortable, and that it's light in there," Keller said.

This Queen City test is a great business opportunity for Kalwall, which prides itself on being technologically ahead of the pack, but it's also an exciting example of basic research changing basic life.

"Most of the technology making this possible came from the entrepreneurial side - one guy in a laboratory devoting his life to working on making it work," Keller said.

The key was new manufacturing processes, done in Germany, which lowered costs to real-world levels.

"It manufactures the material chemically rather than relying on terrific heat and pressure ... to explode these molecules, like popcorn," he said.

Cabot, a $1.7 billion-a-year firm, hopes to use aerogel as a superlight insulator in everything from cars to clothing. It's already available in some material for polar explorers.

But for now, Manchester is the place to go if you're an aerogel fan. And many people are, it seems, aerogel fans.

"We've had a lot of tours of engineers," Bailey said.


Joel Nelson oversees the facility at the Comfort Inn in Manchester, where a new roof covers the swimming pool. Kalwall of Manchester has developed material used in the high-tech roofing that keeps it lightweight, allows light to pass through and has higher insulating properties than the former plexiglass structure.