Single-Ply Cool Roofing Systems
Many single-ply roofing systems have become popular in commercial applications due to their long-term performance, easy maintenance, and life-cycle cost benefits. Some of them have emerged as the best long-term cool roofing options. Their common attribute: high reflectivity.
- Polyvinyl chloride (PVC) single-ply roofing systems have the best track record of long-term performance among white single-ply cool roofing systems. The first white PVC systems were installed in Germany during the 1960s, and their overall performance and life cycle cost benefits made these early systems popular in Europe during the 1970s and ’80s.
- Chlorosulfonated polyethylene (CSPE) single-plies were the earliest widespread white roofing systems in the U.S., introduced in the 1970s under the Hypalon® brand. Although effective as a cool roofing system, Hypalon has not achieved the same commercial success as PVC, EPDM and other single-plies.
- More recent cool roofing single-ply developments include the introduction of thermoplastic polyolefins (TPOs) and certain new co-polymer alloys (CPAs) during the late 1980s and 1990s.
Today, many single-ply roofing systems are available in white, including EPDM and modified bitumen, but PVC and TPO systems are the most popular and best-performing in terms of long-term reflectance. The National Roofing Contractors Association (NRCA) has identified the PVC/TPO thermoplastic single-ply category as the fastest growing roofing sector in America for several years. The coolest among these systems typically have solar reflectance ranging from 70 percent to 85 percent.
Installing a single-ply cool roofing system can save energy and money for building owners all over the United States.
The Cool Roof Rating Council was created to develop accurate and credible methods for evaluating and labeling the solar reflectance and thermal emittance of roofing products. The CRRC’s web site enables you to search for rated products as you investigate roofing systems that will help make your building as energy-efficient as possible.
In our final installment we will discuss Regulatory Incentives and Mandates.