Freres curved PDX roof 1

Mass Ply panels are a sustainable timber product that allows builders to reduce the use of steel and concreate in a wide variety of structures, including residential high-rises. They allow construction to occur quickly, even on small urban lots. They even play a key role in the massive timber roof that covers Portland International Airport’s new main terminal.

Freres Engineered Wood has operated in Oregon for more than 100 years, and Its facilities in Mill City have long produced plywood and veneer. In 2017, Freres opened the $40 million plant that produces Mass Ply, a cross-laminated timber (CLT) product composed of glued layers of veneer.

Typically, CLT products combine thicker layers of dimensional lumber. In contrast, each inch of Mass Ply panel contains nine layers of Douglas fir veneer glued together with resin. One-inch panels – called lamellas – can, in turn, be glued together and machined to produce a wide range of structural building components. Freres can produce Mass Ply beams and columns up to two feet thick, four feet wide and 48 feet long. Individual panels can be up to 12 inches thick, 12 feet wide and 48 feet long.

Its strength and versatility allow Mass Ply to be used in a range of projects that otherwise might use concrete and steel. One recently completed project is the 1510 Webster project in downtown Oakland, Calif. The 19-story mixed-use housing development is one of the tallest mass-timber projects in the country. The floors of 1510 Webster are composed of thick layers of Mass Ply rather than concrete, which can require up to seven days per floor to install. Using Mass Ply, each floor required only six hours to install. And because Mass Ply is relatively light and easy to work with, fewer people are needed to complete a project.

Replacing concrete with Mass Ply also can reduce a project’s carbon footprint. The president of oWow, which built 1510 Webster, estimates that each cubic yard of wood that replaces a similar volume of concrete prevents the release of two tons of carbon dioxide.

Structures that use Freres Engineered Wood’s Mass Ply panels can be found in Oregon, too. Projects include the Chemeketa Community College Agriculture Complex, the Santiam Canyon School District’s new gym and the Meyer Memorial Trust’s new headquarters in Portland.

The highest profile use of Mass Ply to date is, of course, the nine-acre roof that tops the new main terminal at Portland International Airport (see photo above). The roof diaphragm – the outer shell connecting the structure’s exposed wooden beams – consists of Mass Ply panels. Because the roof undulates, each curved panel is unique.

Go here to learn about the A-dec 500 Dental Chair, the other finalist in the Coolest Thing Made in Oregon contest.

Chemeketa CC ag complex

Mass Ply panels are used in the beams, ceilings and other components of the Chemeketa Community College agriculture complex.

Santiam gym

The Santiam Canyon Junior/Senior High School gym features Mass Ply walls, roof, beams and columns.

Mass Ply cross section

Mass Ply panels contain nine layers of veneer per inch, and panels can be glued together to increase thickness.