Mad River Mass Timber (MRMT) has opened California’s first commercial dowel laminated timber (DLT) facility, drawing on research from Assistant Professor Paul Mayencourt and the UC Berkeley Wood Lab.
Reported by UC Berkley yesterday, MRMT is using red fir, hemlock, Ponderosa pine, and other underutilised species to produce mass-timber panels without adhesives, a system that could restore forests, reduce fire risk, and speed up housing delivery.
Working with Mayencourt, it processes small‑diameter, low‑value, and even fire‑damaged trees into structural panels…and as the state’s first vertically integrated mass timber plant, MRMT lower-value tree species into prefabricated floors, roofs, walls and beams.
Previously covered by Wood Central, DLT’s appeal lies in its versatility. Unlike cross-laminated timber, it can be made from species that rarely enter the structural market. And because the panels are held together with wooden dowels rather than chemical adhesives, which makes them fully recyclable and easier to process at the end of a building’s life.
“It’s essential that we reimagine how we build,” according to Mayencourt, who has been studying ways to use undervalued California species in mass timber systems. Until now, most mass timber used in California has been trucked in from Washington or Canada, a supply chain that undermines the environmental benefits, but MRMT’s DLT offers a way to close that gap.
For company president George Schmidbauer, a fifth‑generation sawmill operator, the technology also solves a practical challenge. California’s species mix and sawmill infrastructure are poorly suited to cross-laminated timber, the dominant mass timber product in North America.
“With DLT, we can put lower‑value wood into panels and engineer around that species’ reduced structural capacity,” he says. “This means we can connect forest restoration and wildfire mitigation to the low‑carbon construction economy in more ways than previously possible.”
Schmidbauer first encountered DLT after visiting the UC Berkeley Wood Lab, where Mayencourt was experimenting with small‑scale prototypes. The two then began meeting weekly to troubleshoot the process and explore how to scale it.
And with support from the Joint Institute for Wood Products Innovation, Mayencourt and research associate Jitske Swagemakers were designing early DLT projects in the Tahoe region, while Schmidbauer worked on the manufacturing side in Humboldt County. To reach commercial production, MRMT designed and built its own DLT machine using standard components. The company is now supplying prefabricated panels for a range of building types, and Mayencourt helped write the design guide for the system, based on existing building codes.
The next frontier, however, is in affordable housing. Drawing on Schmidbauer’s background in affordable housing development and the Wood Lab’s design expertise, MRMT is developing prefabricated DLT kits for rapid‑build multifamily projects, which could help a state struggling with housing shortages.
