Nailed down

Most recycled wood is turned into biofuels, alternative daily cover or landscaping products. But what if lumber could be reused in its existing form?

Urban Machine, an Oakland, California-based robotics startup company, has developed an artificial intelligence (AI) solution to allow construction and demolition (C&D) recyclers to recycle lumber from construction debris, salvaging wood waste to reuse as locally sourced, premium lumber products.

Lumber often isn’t reused today because it’s typically filled with metal fasteners—nails, screws and staples—that can’t easily be removed at recycling facilities. Urban Machine’s solution uses AI technology and robotics to efficiently extract fasteners from dimensional lumber, from two-by-fours to six-by-eighteens.

If it works as intended, the AI technology will allow C&D recyclers to accept lumber from contractors, clean it up and sell it back to the lumber market as premium reclaimed wood.

Pilot projects

Urban Machine has been testing the technology in pilot projects at C&D recycling facilities, including Zanker Recycling in San Jose, California, as well as Napa Recycling & Composting Facility and Devlin Road Recycling and Transfer Facility, both in American Canyon, California.

Zanker, one of the nation’s largest C&D recyclers, processes everything from wood to metal and aggregates at its facility. The company’s feedstock matched what Urban Machine was looking for in a partner for its pilot projects.

“Our company was perfectly suited to give a platform for testing this technology,” says Jerame Renteria, director of marketing and business development at Zanker Recycling partner company GreenWaste Recovery Inc.

As part of the pilot program, Urban Machine took its AI machines to run at the Zanker facility for a couple months. Material was brought to the AI machine from different tipping floors, including the facility’s designated wood waste tipping floor, the AI solution was able to recover a number of different materials, Renteria says, including old-growth lumber, quality two-by-fours and engineered wood.

“Overall, it’s really cool technology that we would love to incorporate in the future,” Renteria says.

“Reclaimed wood carries its history on every panel, each scratch and scar, each stain from its previous life, and the markings created through natural weathering.” — Urban Machine

Devlin Road Recycling General Manager Steve Kelley says he’s been happy to work with Urban Machine to provide feedstock for a pilot project. Successful recycling and reuse requires end users looking to use material for the production of new products—and this technology offers the potential to reuse an existing product in its current form, he explains.

“[Our] staff are always looking at new technologies within the industry to find different opportunities to recycle or reuse products and materials that are commonly used and discarded,” Kelley says. “Dimensional lumber is a good product that can be reused if the fasteners are removed and the lumber is still in relatively good shape.”

The Devlin Road Recycling and Transfer Facility is a C&D processing facility that receives a significant amount of used dimensional lumber and other construction and demolition materials daily. Urban Machine has set up a processing site at nearby All Bay Mill & Lumber Co., located about a mile from the Devlin Road facility in American Canyon.

The Devlin Road staff sorts out good, clean dimensional lumber, Kelley says. Once they find lumber that is suitable for the Urban Machine fastener extraction process, they’ll place the lumber in racks provided by the startup.

When they have filled enough racks, the staff notifies Urban Machine to come pick up the collected lumber to deliver to All Bay, exchanging the full racks with empty racks to continue gathering suitable lumber for the project.

“We would definitely consider the opportunity to use the technology to be able to generate good second-use opportunities for reclaimed lumber,” Kelley says.

The Zanker pilot project has concluded and the Napa pilot is ongoing, says Aschley Hopkins, director of sales at Urban Machine.

Company history

Urban Machine was co-founded by Eric Law, a construction industry veteran whose passion for sustainability led him to seek alternatives to landfill disposal, and partners Andrew Gillies and Alex Thiele. Gillies developed the robotics prototype to automate metal fastener removal, while Thiele created the AI software to power the automated machine.

The automated solution is mobile and can reclaim large volumes of wood on-site. The technology promises diversion rates of up to 100 percent. The robot is designed to drive down time and cost for recyclers, and Urban Machine has an ultimate goal to reclaim 50 percent of the 37 million tons of wood waste thrown away in the U.S. each year, Law says. The company’s goal is to have more than 12 machines operating in metropolitan areas by the end of 2025.

The machine uses precision end- effectors, high-speed gantries and vision systems to locate and remove nails, screws and staples using robotic arms. Reclaimed wood is then cleaned and marketed to architects and contractors to incorporate into new construction projects.

Urban Machine sells a selection of salvaged lumber, from Douglas fir two-by-fours to old-growth wood planks, on its website. The All Bay facility also is producing dowel- laminated timber using lumber reclaimed by Urban Machine technology, further contributing to sustainable construction practices through the recycling of materials.

In addition to the high quality of lumber, which is often 40 to 100 years old, the company touts the carbon retention and circular economy benefits of reusing lumber versus building with virgin materials. “During growth, wood absorbs 1 ton of carbon per cubic meter. By keeping the same timber in circulation, we avoid releasing that carbon dioxide into the atmosphere,” Urban Machine says. “Reclaimed wood carries its history on every panel, each scratch and scar, each stain from its previous life, and the markings created through natural weathering.”

The author is managing editor of Construction & Demolition Recycling and can be reached via email at smann@gie.net.