Roofs to Roads

Every year, 4,800 tons of roofing tear-off shingles are dumped into Marin County landfills. But it doesn’t have to be that way. Discarded roofing shingles represent an incredible opportunity to turn construction waste into an asphalt base for paving. What’s more, using roofing shingles as part of the paving process not only diverts waste from the landfill, it makes the paving end product better.

The Marin Builders Association (MBA), in partnership with Marin Sanitary Service and ZeroWasteMarin.org, has launched the Roofs to Roads pilot project. Started in March, it encourages local roofers to recycle composition shingles at Marin Resource Recovery, located at 565 Jacoby Street in San Rafael. Already this year, 236 tons of roofing tear-off have been turned into renewable asphalt base for paving.

Brian McLeran, owner of McLeran Roofing, Inc., in San Rafael, and chair of the Marin Builders Association’s Roofs to Roads committee, states, “Our company worked with Marin Sanitary Service to see what we could recycle by starting with simple things. We quickly found we could save money by diverting some roofing tear-off from the landfill. From there, we pulled together all of the county’s licensed contractors, and now Marin is recycling composition shingle tear-off. This is an exciting first step!

“Other common roofing types include wood shake and tar-and-gravel. Our next step is to recycle the tar-and-gravel at Redwood Landfill, where we’ll turn it into road base.”

An improved product

Everyone understands the environmental benefits of recycling and striving for zero waste. The challenge with many recycling endeavors is weighing a compromised end product (made from recycled goods) against the environmental benefits of reuse. That problem doesn’t exist with the recycling of 
tear-off shingles. Because the shingles are made of asphalt, the product is 
easily converted into paving materials that actually improve the end product. MBA isn’t currently conducting any study of environmental trade-offs or impacts, but it’s known that the current limitation by Caltrans on the use of recycled asphalt shingles (RAS) in hot mixed asphalt (HMA) is 5 percent. Asphalt grades use varying amounts of heavy oil, but, in general, RAS is likely replacing approximately 50 percent of the oil needed in new HMA. 

There are many benefits to recycling roofing tear-off. Not only does it reduce the amount of material going to landfill, it also increases the life of pavement by reducing fatigue cracking, increasing the pavement’s resistance to wear and moisture and decreasing its vulnerability to rutting (in asphalt roads). So for many reasons, recycled shingles represent a more economical option.

Dave Garbarino of Marin Sanitary Service and a board member of the Marin Builders Association claims, “This will result in a great reduction of tonnage going to the landfill. We’re looking forward to this partnership with the roofing community.”

Zero Waste Marin

One of the reasons this program is so important is, in 2006, the Marin County Hazardous and Solid Waste Management Joint Powers Authority (JPA), along with a group of Marin’s community members, began to wonder, “Is it possible to completely eliminate waste in Marin? Can we really live a waste-free life?” The Zero Waste Marin by 2025 initiative was founded to answer this question.

The JPA helps residents and businesses reduce and recycle their solid waste and safely dispose of hazardous materials. It provides household hazardous waste collection, information on recycling and disposal, and ensures the county’s compliance with state recycling mandates—all while educating the citizens and businesses of Marin.

As part of the Zero Waste plan, 10 categories of items—those that generate the most landfill waste—were turned into individual challenges. Many are simple changes, such as eliminating plastic water bottles and grocery bags, using cloth or microfiber instead of paper towels, composting and choosing recycled goods whenever possible.

Asphalt shingle recycling (ASR) has been taking place since the 1980s in the eastern and Midwestern United States. Roofs to Roads is a perfect example of taking a plentiful waste stream and turning it into a recyclable resource that will prevent the use of virgin materials. About 95 percent of homes in Marin County currently have composite asphalt shingles, and a typical asphalt shingle roof has a lifespan of about 30 years.

Roofers who are interested in participating in this pilot program must be educated on the proper procedures and set up an account with Marin Sanitary Service. All roofers who recycle tear-off shingles will receive a discounted rate. For more information call Dave Garbarino, vice president, Marin Sanitary Service at (415) 456-2601 or Nicholas Minton, Resource Recovery & Recycling Operations at (415) 485-5647.