Making Green Building Blocks from Recycled Pallets

What happens when you combine recycled wood pallets, a passionate entrepreneur working out of a shuttered lumber mill in rural Oregon, a dash of cement, and an Oregon BEST researcher who runs a seismic research lab in downtown Portland?

First: a green building construction product that uses fewer resources and lowers energy costs. And second: more new sustainable jobs for Oregonians.

And if things go as planned, this unique product might more widely replace stick-framed structures because it is designed to last decades longer, is much more energy efficient, and is easier to work with.

Here’s what’s happening, and how Oregon BEST is involved. A small business called ShelterWorks, Ltd. is located in a former lumber mill building on the outskirts of Philomath, Oregon (a few feet from the company’s front door stands an abandoned wigwam burner, a rusting relic from the hey-day of the timber industry). Company president, Tom Van Denend (pictured with blocks), connected with Oregon BEST researcher and Portland State University professor Peter Dusicka (pictured, below) to help with testing of its interlocking building block wall system called FasWall, which is made of 85 percent mineralized wood chips from recycled pallets bonded together with 15 percent Portland cement.

The hollow blocks, known as ICFs (Insulated Concrete Forms), are stacked, threaded with rebar, and filled with concrete. They are mold proof, breathable, and lightweight. And because the blocks contain no polystyrene, there is no out-gassing, VOC’s, or formaldehyde, something that many Insulated ICFs can’t boast. Although the blocks meet or exceed building and energy codes in all 50 states and are being used in residential applications, in order to be accepted more widely the wall system needs additional testing for seismic integrity and other factors.

That’s where Dusicka’s expertise and lab facility capability come in. He has been working with Van Denend on a range of testing at PSU's iSTAR (infraStructure & Applied Research) Laboratory, a signature research facility of Oregon BEST.

“I’m interested in new structural systems, especially in the area of green building applications,” Dusicka says. “And I’m most intrigued by companies using non-conventional and recycled materials.”

So ShelterWorks is an ideal fit, and the collaboration has gone well. Dusicka and his graduate students helped quantify the performance behavior of small scale sections of wall made from the FasWall blocks. The researchers analyzed the role the recycled materials have on the structural integrity and investigated practical details that would positively influence the structural performance. In the end, the news was positive.

“We’ve had good, useful results even on the small scale,” Dusicka says.

When one takes into account the ease of assembly (the blocks are much lighter than traditional concrete blocks), the thermal capacity, and the long-term durability, it is a very competitive construction system, Dusicka says.

“ShelterWorks has been excellent to work with. They’re really interested in doing things right,” Dusicka said. “Tom’s a great guy with a long term vision, and we’d like to find the funding necessary to work with him longer term as a research partner.”

Additional testing and research is also what ShelterWorks wants, so the company can expand into commercial markets and areas with stricter seismic codes.

“We need to get our product code-certified using cyclic seismic testing, which is what Peter’s lab does,” says Van Denend, who believes the product has the capacity to contribute structurally to commercial buildings, instead of just providing a shell.

“Peter and I have a similar perspective on green building, and we have developed a very good working relationship. His research proved our product (a shell) has structural value, clearly showed a structural contribution, and makes it obvious that this is worthy of further investigation.”

Van Denend hopes to ultimately decrease the amount of concrete infill and boost the structural role, which will increase the insulating capacity of the wall system because less concrete will be needed. And less concrete makes for a greener building.

Oregon BEST is working to help make the next level of testing a reality, so that ShelterWorks, which currently employs nine people, can market their Oregon-made product more widely.