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EP-4737117-A1 - COVER BOARD FOR THERMALLY JOINED ROOFING ASSEMBLIES

EP4737117A1EP 4737117 A1EP4737117 A1EP 4737117A1EP-4737117-A1

Abstract

A roofing cover board, having: a top layer having a greater affinity to bond with TPO than PVC; a core layer including recycled material; and a bottom layer having a greater affinity to bond with PVC than TPO.

Inventors

  • MOUNTAIN, Gregory

Assignees

  • Carlisle Construction Materials, LLC

Dates

Publication Date
20260506
Application Date
20251028

Claims (15)

  1. A roofing cover board, comprising: a top layer having a greater affinity to bond with TPO than PVC; and a bottom layer having a greater affinity to bond with PVC than TPO.
  2. The roofing cover board of claim 1, wherein at least one of the top and bottom layers comprises recycled material.
  3. The roofing cover board of claim 1, wherein both the top and bottom layers comprise recycled material.
  4. The roofing cover board of claim 1, further comprising: a core layer positioned between the top and bottom layers, wherein the core layer comprises recycled material.
  5. The roofing cover board of claim 4, wherein the recycled material in the core layer comprises paper.
  6. The roofing cover board of claim 4, wherein each of the top, core and bottom layers comprise recycled material.
  7. The roofing cover board of any of claims 2, 3 or 4, wherein the recycled material comprises paper or plastic or blends of paper and plastic.
  8. The roofing cover board of claim 1, wherein the top layer comprises recycled TPO, PE or PP.
  9. The roofing cover board of claim 1, wherein the bottom layer comprises recycled PVC.
  10. The roofing cover board of claim 1, wherein the bottom layer comprises: a core portion made of recycled material, and a facer on the bottom of the core portion.
  11. The roofing cover board of claim 1, wherein the facer is made of: cellulose, kraft paper, a glass mat or a plastic film.
  12. The roofing cover board of claim 1, wherein the top layer comprises a core portion made of recycled materials.
  13. The roofing membrane of claim 4, wherein the core layer comprises shredded paper or shredded or granulated post-consumer or post-industrial plastic films.
  14. The roofing membrane of claim 1 or 4, wherein at least one of the core layer, or top or bottom layers comprise fillers, including but not limited to, calcium carbonate, barium sulfate, talc and clay.
  15. The roofing membrane of claim 9, wherein the core portion comprises: shredded paper or shredded or granulated post-consumer or post-industrial plastic films; and/or fillers, including but not limited to, calcium carbonate, barium sulfate, talc and clay.

Description

Related Application: The present invention claims priority to U.S. Provisional Patent Application Serial No. 63/713,437, entitled Improved Cover Board For Thermally Joined Roofing Assemblies, filed October 29, 2024, the entire disclosure of which is incorporated herein by reference in its entirety for all purposes. Technical Field: The present invention relates to cover boards for TPO and PVC roofing systems. Background of the Invention: Cover boards are typically installed on top of blocks of roofing insulation material. A top roofing membrane is then installed thereover (e.g.: rolled out and attached) on top of the cover board. Roofing membranes are typically made of materials like TPO and PVC. Adhering TPO or PVC roofing membranes on top of the cover board is typically done with adhesives. Unfortunately, TPO and PVC materials have very different polarities meaning that unique adhesives must be formulated to adhere to either of these materials. As a result, a typical cover board can only be used with a subset of adhesive chemistries based on the surface properties of the cover board. In addition, thermally joining the roofing membrane to the cover board or insulation material requires similar facer chemistries to be chosen to match the surface energy properties of the membrane to permit proper thermal welding and joining. It would instead be desirable to provide a cover board that can be used with either a TPO or a PVC roofing membrane. As will be shown, the present cover board system can be used with either TPO or PVC roofing systems, as desired. Secondly, to reduce pollution, it has become desirable to use recycled materials in roofing systems when possible. For example, when TPO roofing materials have finished their normal lifespan of use, they are simply removed from buildings and are sent into landfills. What would instead be desired would be systems for recycling these old TPO roofing membranes such that they are not simply discarded after they have reached the end of their operational lives. In short, finding a way to recycle TPO roofing membranes into desirable new building materials would cut down on landfill pollution. The same is true for PVC roofing. Specifically, when PVC roofs need to be removed and replaced, they are also simply broken up and sent to landfills. It would instead be desirable that both TPO and PVC roofs could be recycled such that some of these materials can then be re-used in new roofing systems. Generally speaking, there are many other materials (including various paper products, plastic products and even textiles) that would benefit from being recycled. Ideally, it would be desirable if such materials could be used in roofing systems and cover boards in particular. As will be shown, the present system incorporates many different recycled materials to provide a novel cover board solution that can be quickly switched to work well with either a TPO or a PVC roofing membrane. As will also be shown, this will be possible when either adhesives or induction welding is used to attach the roofing membrane onto the top of the present cover board. Summary of the Invention: The present invention provides a cover board having top and bottom layers that have different surface properties. Specifically, in preferred embodiments, the top layer is designed to bond well with TPO and the bottom layer is designed to bond well with PVC. Advantageously, this is true whether the bonding is performed either with adhesives, hot air welding or with induction welding. During installation, the operator simply places the TPO-friendly top layer on top when attaching a TPO roofing membrane thereover (i.e.: to the TPO-friendly side). Conversely, the operator simply flips the cover board upside down thereby placing the PVC-friendly layer on top when attaching a PVC roofing membrane thereover (i.e.: to the PVC-friendly side). In preferred embodiments, the present invention provides a roofing cover board, comprising: a top layer having a greater affinity to bond with TPO than PVC; anda bottom layer having a greater affinity to bond with PVC than TPO. In preferred embodiments, either or both of the top and bottom layers comprise recycled materials. Preferably, the recycled materials in the top layer are formulated to promote bonding to TPO roofing membranes and the recycled materials in the bottom layer are formulated to promote bonding to PVC roofing membranes. Most preferably, the top layer includes recycled TPO and the bottom layer includes recycled PVC. This advantageously permits a quick and easy installation as the same cover board can be used with either TPO or PVC roofing, and the operator only has to flip the correct side of the cover board up and then complete the installation of the desired roofing membrane on top. In other preferred embodiments, the roofing cover board further comprises a core layer positioned between the top and bottom layers. This the core layer comprises recycled material. Pref