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
| Jun 5, 2012
OSHA launches campaign to warn of heat dangers in outdoor work
The Occupational Safety and Health Administration has begun a campaign to warn outdoor workers about the dangers of heat exposure.
| Jun 5, 2012
AGC’s Safety and Health Conference focuses on regulations, legislation
More than 150 industry professionals and other attendees will participate in the Associated General Contractors of America’s (AGC’s) safety and health conference July 11-13 in Washington, D.C.
| Jun 1, 2012
New BD+C University Course on Insulated Metal Panels available
By completing this course, you earn 1.0 HSW/SD AIA Learning Units.
| May 31, 2012
Proposed change in Michigan’s building code would hurt innovation, say critics
Legislation pending before the Michigan Senate would change the law that calls for building codes to be updated every three years to require an update only every six years.
| May 31, 2012
Natural gas industry opposes federal carbon-neutral construction rule
The natural gas industry and some allies are working to block a federal green building rule that was expected to be a national model for carbon-neutral construction.
| May 31, 2012
Lawsuits push the legal boundaries of green building definition
This article explores some legal issues stemming from lawsuits in which plaintiffs have charged developers with not delivering on a promised level of sustainability.
| 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.