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
Codes and Standards | Aug 10, 2021
Dept. of Energy issues model energy code determinations for commercial, residential buildings
2021 IECC offers 9.4% site energy savings.
Digital Twin | Aug 9, 2021
Digital Twin Maturity white paper offers guidance on digital twin adoption
Provides lifecycle map and an approach for incorporating digital twins.
Codes and Standards | Aug 5, 2021
Contractors can be liable for building failures many years after project completion
Personal injury suits could be brought decades after substantial completion.
Codes and Standards | Aug 4, 2021
Mass timber is a natural choice for building recycling through deconstruction
Designing wood buildings to optimize recovery of materials for disassembly aids carbon sequestration.
Codes and Standards | Aug 3, 2021
Dept. of Energy releases initial version of the Spawn of EnergyPlus software
Targets new use cases in advanced controls, district systems, and grid integration.
Codes and Standards | Aug 2, 2021
Several U.S. cities among most expensive places to build in the world
San Francisco, New York, and Boston head the domestic list.
Codes and Standards | Jul 28, 2021
American Concrete Institute creates new director of innovative concrete technology post
Aim is to attract emerging technologies for development.
Codes and Standards | Jul 28, 2021
Higher ed faces infrastructure backlog of $112.3 billion
Study recommends integrated strategic planning for best results.
Codes and Standards | Jul 27, 2021
Add a wobbly moon to flooding risk factors
Earth satellite’s orbit variations will lead to sunny-day flooding in the mid-2030s.
Codes and Standards | Jul 26, 2021
Revamping of Florida building codes on the table after condo collapse
Tragedy could prompt upgrades like post-Hurricane Andrew effort.