Uses for processed Shingles
Hot Mix Asphalt shingles, which account for two-thirds of the U.S. residential roofing market, are made from a fiberglass or organic backing, asphalt cement, a sand-like aggregate and mineral fillers such as limestone dolomite and silica. These are the basic ingredients of hot-mix asphalt used in road construction, which helps explain why the paving industry is the No. 1 end user of reprocessed shingles.
Cold patch for repairing potholes. Ground-up shingles mixed with aggregate and an emulsion can be used for patching roads. In fact, the mix actually improves road strength because of the fiberglass or cellulose content of the shingles.
Aggregate in road construction. Ground and screened shingles can be mixed with gravel and used to cover unpaved roads, minimizing dust, reducing vehicle noise and longer road life. Combined with ground asphalt and concrete, ground shingles also make a good road base for driveways.
Manufacturing new shingles. Some shingle manufacturers have tried using factory scraps to make new shingles, with mixed success.
Energy recovery. Shingles have an energy content of as much as 20,000 Btu per pound and the practice of using scrap as a fuel supplement is an established market in Europe. Some industries like cement manufacturers in the USA, are using old shingles as fuel.