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Recycled Asphalt Pavement (RAP) is commonly used as a component of new asphalt. Washington State Department of Transportation (WSDOT) allows the use of up to 20 percent RAP in new pavement.

Recycled asphalt shingles (RAS) can be processed into a ground product and used for road applications as a percentage of hot mix asphalt (HMA) pavement and cold patch. The manufacturing of warm mix asphalt (WMA) occurs at lower temperatures, using less fossil fuels to produce, creating 24 percent less greenhouse gases, and costing less than HMA.

In King County, the Solid Waste Division estimates that 40,000 tons of asphalt shingle waste is disposed each year and they have worked on developing local recycling markets for the material.



  • up to 20 percent RAP
  • up to 20 percent RAS
  • WMA instead of HMA


  • virgin asphalt

End of Life

  • recycling "where available"

An EPA checkmark indicates a certification or standard is recommended by the U.S. Environmental Protection Agency (EPA).

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