The present invention relates to a composite roofing overlay containing recycled paint waste and recycled crushed glass, and more particularly, to a composite roofing overlay for use on new or existing roof surfaces.
Low-sloped roof construction is used for a wide variety of commercial and industrial buildings. Typically, low-sloped roofs include a waterproof layer or membrane which prevents the penetration of water resulting from precipitation or condensation on the roof surface. Where the waterproof layer comprises a membrane, the membrane may be comprised of materials such as EPDM rubber, thermoplastic polyolefins (TPO), polyvinyl chloride (PVC), chlorosulfonated polyethylene, and modified bitumen. The waterproof layer may also comprise a composite including layers of hot applied asphalt, reinforcing fiberglass, cloth, or paper. Elastomeric sealers may also be used in combination with cloth to form a water-resistant membrane. A number of additional layers may be included below the membrane such as insulation, supporting cover boards, and various vapor or thermal barrier layers.
Re-roofing an existing low-sloped roof is an expensive process as it typically requires tearing off the existing roof. In addition, there is a period of time during the re-roofing process in which the inside structure is exposed to outside weather elements, rendering the inside structure vulnerable to water damage. Further, tearing off an existing roof structure is environmentally undesirable as most of the components are discarded in a landfill, and the underlying components, such as insulation, also have to be replaced. Accordingly, it would be desirable to restore the existing roof.
In order to avoid the expense of removing and replacing an entire roof, an increasing emphasis has been placed on applying a secondary roofing system over an aged roof which allows all of the sub-roof layers to be utilized. Currently, the application of an EPDM or TPO membrane is widely used in re-roofing processes. In conjunction with the application of such a membrane, the underlying substrate which supports the membrane is important. Typical support substrates which have been used below roofing membranes include cover boards such as iso-board, asphaltic board, mineral fiberboard, fiberglass board, plywood or oriented strand board (OSB), wood fiberboard, or mineral aggregate board. While these materials generally lie flat in new construction, when used in reroofing applications, they may cause improper sloping, blisters, bubbling, raising, or seam separation due to the multiple underlying layers. In addition, support substrates comprised of these materials are not generally waterproof, and therefore not capable of preventing water infiltration into the roofing system in the event that the roof cover becomes compromised.
It would be desirable to provide an improved support for a roofing membrane which does not suffer from the drawbacks of roofing substrates such as cover boards.
Accordingly, there is a need in the art for a substrate which may be used in conjunction with a roofing membrane for use in new roofing construction or on an existing roof which is cost-effective, environmentally friendly, and which provides effective sealing and adhesion characteristics.