Additional survey results show that asphalt producers used an estimated 921,000 tons of reclaimed asphalt shingles (RAS) in asphalt mixtures in 2019. RAS usage during the 2019 construction season is estimated to have reduced the need for 184,200 tons (more than 1 million barrels) of asphalt binder and about 460,000 tons of aggregate with a total estimated value of more than $103 million.
Other recycled materials commonly reported include recycled tire rubber, blast furnace slag, steel slag, cellulose fibers, and fly ash. Fifty-two companies in 24 states reported nearly 1.3 million tons of these other recycled materials in the production of nearly 8.3 million tons of asphalt mixtures.
Asphalt mix producers also continue to make significant use of energy-saving warm-mix asphalt (WMA) technologies. In 2019, contractors used WMA technologies for the production of 164.5 million tons of asphalt mix. A number of environmental, worker safety, and construction benefits have been realized through the adoption of WMA technologies. Nearly half of the WMA production was at reduced temperatures decreasing the energy required to manufacture the mix. The most common WMA technology used is plant-based foaming, which injects a small amount of water into the asphalt binder during production.
NAPA collected survey responses over the first half of 2020. The report compiles results from 212 companies with 1,101 plants in 48 U.S. states, the District of Columbia, and one U.S. territory.