Design evolution

Maximum daylighting remains a top green priority, as building designers continue to look for ways to lower energy costs. However, the trend toward heavily day-lit structures has evolved in recent years, as architects increasingly account for solar heat gain and glare. “In the past, designs would just attack with high transmittance products to get natural daylight, and it would have the potential to create other problems,” says Greg Carney, president, C.G. Carney Associates, Gulfport, Miss. “I’m certainly seeing the use of transmittance products, with other considerations,” he says.

Examples of this trend appear on the following pages in the form of four green projects: the 1050 K St. office building in Washington, D.C.; the Consol Energy Center hockey arena in Pittsburgh; the Sarasota (Fla.) Police Headquarters; and the Silver Lake Branch Library in Los Angeles. Despite different building segments and geographic locations, all of these projects rely heavily on glass to provide natural daylight deep into the building, reducing the energy costs associated with artificial lighting. They also feature a variety of complementary shading tools—sunshades, fritted glass, translucent products and automatically controlled interior shades—to further curtail costs and improve occupant comfort. In several cases, the architects report that they carefully designed for orientation as well, reducing light infiltration on the elevations with the most sun exposure to address heat gain and glare concerns.

To provide further insight into the projects’ design, Carney offers his glass-related expert opinion on each. Former technical director for the Glass Association of North America, Topeka, Kan., he has about 30 years experience in the glass industry, focusing on technical
applications of architectural glass.