Cool Roofs Could Be "Hot" Issue

Change is a constant in today's roofing market, so organizations have to stay active to deal with continual industry developments. SPRI, representing sheet membrane and component suppliers to the commercial roofing market, participates in a wide variety of related industry activities. For example, SPRI representatives are monitoring a new organization called the Cool Roof Rating Council (CRRC).

CRRC's first meeting was held in September 1997, hosted by Lawrence Berkeley (CA) National Laboratory, which is operated by the Dept. of Energy. Several other roofing associations are also sending observers to CRRC meetings, held every few months.

CRRC was reportedly formed by a number of researchers, academics, government officials, and others concerned with addressing the issue of urban heat islands. Urban heat islands are thought to be impacted by both roofs and asphalt paving on roads and parking lots, which are the largest man-made surfaces in urban areas. Urban heat islands are considered to be closely tied to the number of days of smog formation.

Researchers note there are a number of ways to mitigate heat build-up and poor air quality in cities, such as planting more trees, addressing the issue of heat absorption by asphalt roadways and parking lots, and looking at ways to increase the reflectivity of roof surfaces.

However, the differences between the potential reflectance of roofing materials in their just-manufactured state needs to be compared with how they age and perform over time, roofing experts point out, as well as what the maintenance requirements could be. And while certain roof systems may save energy on certain buildings in certain climates, another key factor is how well insulated the roof is.

And, points out one roofing industry expert, there are benefits to using black roofs in colder areas of the U.S.

Information about CRRC can be found on the Internet through the website of Pacific Gas & Electric, at http:www.pge.com/pec/progtoc/crrc.html.

The web site reports CRRC's mission is to "implement and communicate fair, accurate and credible radiative energy performance rating systems for roof surfaces."

The site also lists the Council's far-reaching goals. These start with "developing a rating system, and developing or utilizing a labeling system for cool roof surfaces that enables... interested parties to easily differentiate products."

Furthermore, CRRC plans to "develop tools that help customers evaluate other features of cool roofs that will affect their ability to provide sustained radiative benefits."

The website continues: "Features may include the following: retention of reflectivity, durability of the radiative roofing product, and compatibility."

Plus, it hopes to "provide analytical tools to help code officials, electric utilities and specifiers/builders accurately assess the energy performance of reflective roofing products, which will aid in product selection, building load estimation and equipment sizing. And develop educational materials and tools that help customers understand the benefits of reflective roofing products, e.g., energy savings, air quality improvement, and extended life of a roof system."

Some observers compare the new CRRC to the National Fenestration Ratings Counci, a third-party organization that developed and issues ratings for windows. However, at the January CRRC meeting, it reportedly was decided that it may be a useful idea to develop a procedure for rating roofs but not to administer a ratings program.

To see for itself how some of these technical issues manifest themselves, SPRI is about to sponsor research at another DOE facility, Oak Ridge (TN) National Laboratory. This joint SPRI-ORNL program is intended to evaluate the intermediate and long-term reflectivity of a variety of thermoplastic roof membranes. One question, for example, is how quickly do materials change.

By planning ahead with studies like this, SPRI will be able to offer hard data on reflective performance over time of specific types of roofing. As one observer notes, "it's good to be ahead of the game."

Like most things, however, the color of a roof surface is not a black and white issue, and it is not yet clear what direction the CRRC's activities will take. Stay tuned for more news on this potentially "hot" issue.