SpecTopics: Single-Ply Roofing Membranes and Recycled Content

In the June 2021 SpecTopics post about Roofing Recycling Programs, we covered the programs available nationwide that recycle re-roof 'tear-off' materials such as insulation and roofing membranes, as well as recycling programs which take back adhesive cylinders for refill after construction is complete on a new roofing system.

In this SpecTopic, we are exploring the recycled content of the new membranes themselves.

Single-ply roofing membranes, whether they be EPDM, TPO, PVC, or KEE HP, are exposed to the weather year-round. From the heat of summer, to the cold of winter, to wind and rain, the single-ply roofing membrane must stand up to all kinds of weather. Throughout its service life, the membrane must repeat this performance year after year. And with roof warranties extending to 25 and 30 years, that performance needs to be assured through correct detailing and installation, as well as proper formulations and manufacturing processes.

Currently, these formulations and processes include post-industrial recycled content varying from 0% to 10%, depending on the membrane selected. These amounts have been tried and tested throughout the years to determine the balance between new material and what can be reused from the production line itself from new scrap material. Material performance and longevity is based on this new material and adding more and more recycled content could degrade the performance of the membrane.

The recyclers who will take roof membranes, post-consumer, grind these membranes into smaller pieces to be used for various industries, such as:

• EPDM – recycled into tires, rubber pavers, or other rubber products.
• TPO/PVC/KEE HP – recycled into flooring, composite plastic materials, or back into the raw material supply chain.

In the case of TPO/PVC/KEE HP being broken into constituent chemicals and put back into the raw material supply chain, that supply chain does not currently track raw material extraction or sourcing. So, unfortunately, there is no way of knowing if these materials came from a recycled roofing membrane or not. But as raw material tracking becomes more prevalent with the advent of green building standards and more product transparency, we are hopeful we can also start tracking the use of post-consumer material as a raw material infeed to our manufacturing process.

To learn more about the recycled content of Carlisle's roofing membranes and products, refer to the individual Product Data Sheets on the website, or check out our Product Sustainability Reference Guide.  

If you have any questions regarding recycled content, please contact Craig Tyler.