ROOFING PRODUCTS, PHOTOVOLTAIC ROOFING ELEMENTS AND SYSTEMS USING THEM

摘要

The present invention relates more particularly to roofing products for use with photovoltaic elements, and to photovoltaic systems that include one or more photovoltaic elements joined to a roofing substrate. In one aspect, the invention provides a roofing product including: a bituminous roofing substrate having a top surface; and roofing granules embedded in the top surface of the roofing substrate, wherein in at least one over-pressed zone of the roofing product, the roofing granules are embedded so that (a) the over-pressed zone exhibits a 0.20 gram loss or less in a rub test as described in ASTM D-4977; or (b) in the over-pressed zone the average granule embed volume fraction is at least 0.5; or (c) in the over-pressed zone, the average distance between the top of the roofing granules and the top surface of the bituminous roofing substrate is 1.0 mm or less.