Although LEED and ASHRAE 90.1 (Energy Standard for Buildings Except Low-Rise Residential Buildings) standards require or reward use of white “cool” roofing to mitigate urban heat island effects, it is not always the best choice of material.
Cool roofs can cast heat where it is not wanted. “Architects and roof consultants need to be aware of potentially adverse thermal effects when choosing roof membranes, particularly where roof surfaces are adjacent to walls that can be affected by bounced sunlight,” says Elizabeth Grant, associate professor in the School of Architecture + Design at Virginia Tech.
Choosing the best material for a commercial roof is a nuanced decision requiring a careful examination of the application. “Roof selection is an architectural issue,” Grant said. “It’s not as simple as slapping a white roof on everything to gain a LEED point.”
The study compared the thermal impact of white and black roofs. The black roof heated the air within 5 ½ inches, but there was no difference in air temperature impact for black or white roofing above that zone. Researchers also found that electrical metallic tubing and glazed and precast concrete wall panels near white TPO roofing were 3 to 9 degrees Fahrenheit warmer than those near black EPDM roofing.
Related Stories
| May 31, 2012
ANSI approves Green Building Initiative’s design standard
The Green Building Initiative (GBI), a Portland, Ore. nonprofit organization, has had its new consensus-based standard for the design, construction, and operations of environmentally friendly buildings approved by the American National Standards Institute (ANSI).
| May 31, 2012
USGBC testing Minnesota buildings to see if they are living up to LEED standards
The Minnesota chapter of the U.S. Green Building Council (USGBC) has teamed up with EnergyPrint, a St. Paul, Minn. energy consulting firm, to study the energy and water use of more than 150 buildings in the state that have LEED certification.
| May 29, 2012
Reconstruction Awards Entry Information
Download a PDF of the Entry Information at the bottom of this page.
| May 25, 2012
Major retail chains welcome LEED Volume option
Large national chains such as Starbucks, Marriott, Verizon, and Kohl’s are welcoming the LEED Volume Program that enables them to batch certify similar projects.
| May 25, 2012
Alaska’s okay of gravel aggregate with naturally occurring asbestos opens up development
Some long-delayed projects in the Upper Kobuk region of Alaska may now move forward thanks to legislation that allows construction in areas that have naturally occurring asbestos.
| May 25, 2012
Las Vegas building codes may thwart innovative shipping container development
A developer wants to build a commercial development out of steel shipping containers in Las Vegas, but city codes would have to be altered or the project would have to obtain waivers for it to receive the city’s go-ahead.
| May 25, 2012
Collapse of Brooklyn building that killed worker blamed on improperly braced frame
The Occupational Safety and Health Administration cited SP&K Construction with 11 safety violations, for which it could face more than $77,000 in fines.
| May 25, 2012
Study: Safety inspections don’t hurt the bottom line
A new study suggests that random safety inspections by regulators help reduce injury claims without hurting profits.
| May 24, 2012
2012 Reconstruction Awards Entry Form
Download a PDF of the Entry Form at the bottom of this page.