Long term, architects might forsake traditional building envelopes
Architects see dramatic changes afoot in the way contract glaziers erect typical building envelopes. Long term, the energy-conservation concepts discussed at the AIA 2006 National Convention June 8-10 in Los Angeles would profoundly affect glaziers’ work.
In just one workshop during the convention, hosted by the American Institute of Architects in Washington, D.C., a team of engineers backed the use of operable windows in naturally ventilated buildings, and presented case studies that show how to go about it. The use of operable windows slightly reduces the total amount of glass in a project.
In countless other seminars, architects encouraged their peers to use canopies, light shelves, screens or shades to keep direct glare off glass and orient buildings to maximize daylight while minimizing solar heat gain.
During a daylong workshop June 7, Joel Loveland, professor of architecture, University of Washington, Seattle, divided approximately 45 attendees in groups of six or seven, and asked them to come up with daylighting criteria and design strategies for existing buildings.
As further evidence of the trend, AIA officials announced June 8 that the U.S. Conference of Mayors approved an AIA-backed resolution to seek energy reduction in all new and renovated buildings to half the national average for each building type until those designed in year 2030 would be “carbon neutral, meaning that they will use no fossil-fuel energy.”
In the session on natural ventilation, Gail S. Brager, professor of architecture at the University of California in Berkeley, said the American Society of Heating, Refrigerating and Air-Conditioning Engineers’ ASHRAE 55-2204, the Adaptive Comfort Standard, sets goals for architects designing naturally ventilated facilities. The research behind the standard was based on studies of 160 buildings on four continents. The data show “people are comfortable in a wide range of temperatures,” she said.
Peter Alspach, an engineer with Arup Partners in San Francisco, named key strategies for achieving natural ventilation including operable windows and vents, wind-assisted ventilation and ceiling fans. Some architects were putting operable windows in some parts of buildings and air conditioning in other parts, he said. Make “air conditioning a thing of the past,” he urged attendees.
Case studies cited included the San Francisco Federal Building now under construction; Berkeley Civic Center; Chesapeake Bay Foundation in Chesapeake, Md.; Big Horn Home Improvement Center in Silverthorne, Colo.; and the visitors center of Zion National Park in Utah. Whereas few of these facilities boast traditional glass curtain walls, in the name of another popular green-building trend—daylighting—some have skylights and solar cells.
Steve Coonen, vice president of sales for the Open Energy Corp. in Grass Valley, Calif., said the photovoltaic market is growing at a tremendous pace in North America. “From 2000 to 2002, the photovoltaic market grew 60 percent each year,” he said. “This year has seen 25 percent growth already, and we’re expecting 50 percent growth by the end of the year.” The PVs cost about $80 per square foot, but there’s a 35 percent tax credit on full systems, he noted.
Solar cells, skylights and their accessories in glass and plastics were prominent on the trade-show floor. For a round up of innovative products from the show, click here.