Birdair, the leading specialty contractor of lightweight long-span roofing systems and tensile structures throughout the world, has completed a retrofit roofing construction project on the Dedmon Athletic Centre at Radford University, Radford, Va (USA).

When considering new roofing options for the 52,000 sq ft Dedmon Centre – nicknamed “The Bubble” by students and faculty – energy efficiency, moisture resistance and sound dampening topped Radford University’s list of priorities. In addition, the university wished to maintain the aesthetic appeal and translucency of the structure’s previous air-supported roof, which was installed by Birdair in 1981 and outlasted its 20-year expected lifecycle by seven years. Birdair’s new Tensotherm with Nanogel offered the perfect solution, the company said.
Developed by Birdair, Cabot Corporation and Geiger Engineers, Tensotherm consists of Cabot Corporation’s Nanogel aerogel sandwiched between two layers of structural PTFE fiberglass membrane. This creates an insulated, energy-efficient inner layer that maintains translucency and promotes natural daylighting. The fabric is less than 50 mm thick, yet it more than quadruples the original roof’s thermal insulation performance with a value of R-12 and natural light transmission value of 3.5 per cent. This durable, fade resistant material also offers maximum moisture control and superior sound insulation. These performance features are permanent, so they will not change over time.
“Projects like the Dedmon Centre call for the beauty and durability of a fabric roof form, but also require a higher level of energy efficiency,” explains James Satterwhite, global daylighting business manager for Cabot Corporation, creators of the Nanogel aerogel insulation used in Tensotherm. “Options to create the balance between design and practicality remained a technical challenge until the advent of Tensotherm with Nanogel.”
By retaining cool air in warm conditions and warm air in cold conditions, Tensotherm with Nanogel meets increasingly demanding energy and building code requirements throughout North America. It can also contribute to Leed certification, garnering credits in categories including insulation, green materials, innovation and daylighting. Nanogel aerogel is additionally cradle to cradle certified.