The present invention relates to a roof coating containing paint, and more particularly, to a reflective roof coating which contains treated paint or paint waste.
Re-roofing an existing roof is an expensive operation, as such an operation typically includes tearing off the existing roof and replacing defective decking, sheathing, insulation, and the like. There is usually 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.
In order to avoid the expense of removing and replacing an entire roof, an increasing emphasis has been placed on products for extending the life of existing roof structures. Such products include asphalt and coal tar cements, as well as caulking, aluminized asphalt, elastomeric sealers, patching tapes, and the like. However, such systems may contain cold tar derivatives, which are known to contain carcinogenic polynuclear aromatic compounds (PNAs).
Moreover, both in restorative and new construction, there is an increasing demand for roofing systems which contain recycled content. For example, the U.S. Green Building Council has promoted recycling efforts in construction through its “Leadership in Energy and Environment” or LEED program.
In recent years, roofing products have been developed which utilize recycled automotive paint sludge as a polymeric component. See, for example, U.S. Pat. Nos. 6,455,598 and 5,880,218. However, while such products are environmentally friendly, the use of large amounts of paint sludge having an inconsistent composition results in a wide variation in the roofing product composition. For example, paint waste may be collected in a number of different ways and can include a variable mixture of several different components including primers, paints, and solvents. In addition, the paint sludge may include other automotive solid waste materials such as production-related trash, metal parts, and the like.
It has also become desirable in recent years for roof coatings which can be easily cold applied to the roof substrate or the existing roof. Additional benefits may be provided when these coatings are reflective in nature as a means of reducing air conditioning demands and energy costs. Some estimates indicate that 15% of a building's cooling cost can be saved through the proper use of a reflective roof surface.
Therefore, it would be desirable to provide a roof coating which provides good reflective properties.
Accordingly, there is a need in the art for a roof coating which will extend the life of an existing roof and which is cost-effective, environmentally friendly, provides effective sealing and adhesion characteristics, good reflective properties, and has low or no VOC content.