Tried and True Approach to Cool Roofs in Cold Climates

Once again, as the temperature begins its downward slide, those of us who live in cool-to-downright-cold climates are faced with the reality that winter will soon be here. And once again, the staff and members of ERA feel the need to remind our extended community of roofing contractors, building owners, specifiers and architects that “cool” roofs in cold climates are not the best choice. That shiny white roof reflecting rather than absorbing the warmth of the winter sun can cause condensation problems, and deliver higher heating bills.

In the rush to embrace environmental correctness and lower skyrocketing energy costs, a tried-and-true approach to reflective roofing has been overlooked, and ERA has worked hard to remind the building industry of the value of ballasted roofing. Simply put, ballasted roofing will save more energy over time than a reflective roof that becomes discolored from air pollutants. This is based on a study from the highly respected Oak Ridge National Laboratory. The research was so compelling that the EPA recently modified language on its ENERGY STAR website to state:

“While the ENERGY STAR program is not structured to apply its label to complete roofing systems, the EPA recognizes that Ballasted EPDM roofing systems are a very effective means of significantly lowering the roof top surface temperature similar to reflective roofing products.

In addition to providing a cooling benefit, Ballasted EPDM roofing systems also save energy by eliminating the 3-8% loss in R-value from the thermal bridging of mechanical fasteners as the natural weight of the stone or paver ballast holds the roofing system in place.

Ballasted EPDM systems are known for their sustainability due to their proven long life cycle, low environmental impact and the recyclable nature of the major components. Ballasted roofs have great aesthetic appeal; eliminate the need for periodic cleaning to retain reflectivity and have well documented resistance to hail damage.”

It’s not just the EPA and Oak Ridge that have supported the use of ballasted systems. Codes and standards, including ASHRAE 90.1, ASHRAE 189.1, California Title 24, and the City of Chicago Energy Code, have changed in the past decade, to allow ballasted systems as an alternative to reflective roofing.

ERA recently asked the city of Philadelphia to amend its Building Construction and Occupancy Code to include ballasted roofing as an exception to its highly reflective roofing requirement. And, as part of our service to the industry, ERA would also like to remind you of the benefits of ballasted. Energy savings winter and summer, without the problems associated with reflective roofing in cold climates. Good sense supported by good science. And a time-tested solution for 21st century roofing requirements.

Ellen Thorp