Roofing shingles into roads
Recycling asphalt shingles
Minnesota annually generates 500,000 tons of post-consumer shingles.
An asphalt shingle contains the same basic ingredients as hot-mix asphalt: aggregate, asphalt cement, and mineral filler.
Laboratory and field testing by researchers at the University of Minnesota and the Minnesota Department of Transportation (Mn/DOT) shows that scrap from asphalt shingle manufacturers (pre-consumer) can be used successfully in hot-mix asphalt. Based on this success, Mn/DOT has issued specifications that allow for the use of up to 5 percent manufacturers' shingle scrap in hot-mix asphalt.
Research and development continues on uses for tear-off roofing waste (post-consumer). Nationally, an estimated 11 million tons of used shingles are landfilled each year.
Toolkit: A guide to the use of roofing shingles in road construction
Fact sheets and additional information about the use of shingle scrap in hot-mix asphalt and other paving applications.
A project of the Minnesota Department of Transportation and the Minnesota Pollution Control Agency.
Bituminous Roadways (Minneapolis, Minn.) has developed an improved processing system for turning shingle byproduct from the manufacturing process into asphalt for roads. Use of 5 percent shingle byproduct improves the performance of hot-mix asphalt, and is cost-effective, with potential cost savings from $0.50 to $1 per ton. BR is currently using 25,000 tons of shingle manufacturing scrap. BR has used the product in mixes for parking lots and residential and commercial roads.
BR is also involved in testing the use of post-consumer tear-off shingles in hot mix asphalt. This next phase will develop a national engineering and environmental specification for the approximately 500,000 tons of post-consumer shingles generated in Minnesota each year.
For more information
Use these contacts for more assistance on the use of shingle scrap in paving applications.
- Improving Recycling of Shingles in Minnesota project:
James Klessig < firstname.lastname@example.org >, Mn/DOT Office of Research Services, 651-282-2472
- Technical assistance on mix-design approvals involving shingle byproducts in Minnesota:
Roger Olson < email@example.com >, Mn/DOT Office of Materials and Road Research, 651-779-5517
- Consultant technical assistance in Minnesota:
Dan Krivit < firstname.lastname@example.org >, Dan Krivit and Associates, 651-489-4990
- Shingle recycling and product development operations in Minnesota:
Kent Peterson < email@example.com >, Bituminous Roadways, Inc., 651-686-7001
- Driving Change: Manufacturer Shingle Scrap Recycling (Krivit, SWMCB, 2004)
Full report (900Kb)
This project examined the barriers to recycling shingle manufacturing scrap (pre-consumer) in the Twin Cities metro area, with additional investigation into expanding into tear-off roofing waste (post-consumer).
- Influence of Roofing Shingles on Asphalt Concrete Mixture Properties (Newcomb, et al., 1993)
Summary & Abstract (4 pages, 38Kb) | Full report (108 pages, 9Mb)
The production of new roofing shingles generates approximately 1 million tons of waste annually in the U.S., around 36,000 tons of which comes from the Twin Cities Metro Area. This report presents the results of an effort to evaluate the use of roofing waste generated by manufacturers and from reconstruction projects. Research showed that up to 5%, by weight of mixture, manufacturing waste roofing shingles could be used in asphalt concrete with a minimum impact on the properties of the mixture.
- Minnesota's Experience With Scrap Shingles in Bituminous Pavements (Janisch & Turgeon, October 1996), Office of Research Services, Mn/DOT
Abstract | Full report (48 pages, 7.5Mb)
- Evaluation of Use of Manufactured Waste Asphalt Shingles in Hot Mix Asphalt (Mallick, et al., 2000)
This laboratory study by researchers at the Worcester Polytechnic Institute and UMass Dartmouth showed that the properties of hot mix asphalt with 3, 5 and 7 percent shingles are not significantly different from the properties of conventional hot mix asphalt used for surface courses.
- Additional Technical Reports from around the country: www.shinglerecycling.org
- From Roofs to Roads: Recycling Asphalt Roofing Shingles into Paving Materials (1998) | 450Kb
Conferences and workshops
- Presentations from the July 2006 summit/workshop reviewing results from lab testing of hot mix asphalt samples are posted on ShingleRecycling.org.
- Presentations from the March 2004 workshop at the Minnesota Asphalt Pavement Association conference are posted on GreenGuardian.com.
- Presentations from Minnesota's March 2003 forum on asphalt shingle recycling are posted on the Mn/DOT web site.
An online resource for those interested in recycling asphalt shingles. Developed by the University of Florida in collaboration with the CMRA, the National Roofing Contractors Association, and U.S. EPA, Region 5.
- Recycled Materials Resource Center || www.rmrc.unh.edu
The RMRC is a national center at the University of New Hampshire created to promote the use of recycled materials (pavements, secondary waste, by-product materials) in the highway environment. They focus particularly on the long-term physical and environmental performance of recycled materials. The RMRC has a unique role in the growing area of recycled materials use in highway construction: They will serve as a principal outreach and evaluator of information for the Federal Highway Administration (FHWA) and the main contact for information about recycling in the highway environment.
- California Integrated Waste Management Bureau || www.ciwmb.ca.gov/condemo/shingles/
California's site discusses the recycling of asphalt roofing shingles, from their share of the waste stream, composition, processing, products, and products made from recycled shingles.