A Perfect Woody Union: Nail-Laminated and Urban Wood

By Kathryn B. Reis, North Carolina Certified Environmental Educator

While perusing my LinkedIn feed today, I saw a post by one of our esteemed urban wood leaders, Jennifer Alger. The U.S. Forest Service Truckee Hotshots recently partnered with Tahoe Prosperity Center, Berkeley Wood Lab, and Tahoe Earth Institute to host an affordable housing workshop in Truckee, California. These four partners showcased how a 150-year-old construction technique can transform national forest harvests into panels for floor, wall, and roof installation.

We all know how our national forests are decades old tinderboxes for wildfires that break annual records year after year. As the U.S. Forest Service conducts land management techniques to thin and restore these forests, the agency needs a disposal plan for the large volumes of wood coming off its public lands. Rather than burning the woody debris or shipping it elsewhere for processing, innovative people have opened their history books to create a more sustainable solution.

And this is where nail-laminated wood meets urban wood.

What is nail-laminated wood?

Anyone can form nail-laminated wood (NLT) by nailing (or screwing) together a succession of boards that are 4 to 12-inches thick. With each mechanical attachment of lumber, the wood panel’s structural integrity increases.

• Type III is any form of “ordinary construction,” such as interior floors, walls, and roofs, primarily among buildings with three to five floors. Since the building material is functional and economical, it may not be fire resistant. Installment of a fire sprinkling system is a must.
• Type IV is any form of “heavy construction” in which large dimensional lumber serves as the structural material. Examples include large wooden beams, columns, and decking found in churches, schools, and historic buildings. The timber’s increased level of thickness, compared to Type III construction, makes it a more fire-resistant choice for builders. Installation of a fire sprinkling system is still warranted.
• Type V is any form of “wood frame construction” in which wood is the main structural material. In addition to dimensional lumber, the wood could be a paneled or engineered product. The wood, however, must be spiked tightly together and be at least 64 mm deep for roof paneling and at least 89 mm deep for floor paneling. This type of wood construction is common among homes and “light” commercial buildings since it is cost-effective and easy with which to build. Installation of a fire sprinkling system is still warranted.

As for architects, they are drawn to nail-laminated timber because it unleashes their design creativity. Want a curved roof or cantilevered stairs in your office building? Use NLT. Want to guard against structural collapse? Cover your NLT panel with plywood or a sheath of oriented strand board to create a shear wall or structural diaphragm.

How was nail-laminated timber historically used?

A quick perusal of an 11 October 2018 article in Treehugger.com reveals examples of nail-laminated timber in recent construction projects, including a 7-story office building that spans 210,000 square feet in Minneapolis, Minnesota. Historically, however, builders used NLT to construct industrial warehouses, factories, bridge decks, and grain elevators. In Saskatchewan, Timberwood Innovations salvages NLT from historic grain elevators in prairie towns to use as floor, wall, and roof panels in new construction projects.

Why the resurgence of NLT today?

In years past, many wooden structures fell to destructive forces of fire. To safeguard the lives of occupants, architects and builders transitioned to concrete and steel for new construction projects. In the 21^st century, however, fire alarms are much more advanced than they were 30 years ago. In commercial buildings, fire alarms often include sprinkler systems. This technological advancement means that architects and builders can return to locally sourced, cost-effective dimensional lumber to embed their creations with zany, warm toned designs.

Want to explore the world of nail-laminated timber creation? Click here to access Timberwood Innovation’s product and design guide. This guide discusses the value, application and installation of NLT in new construction projects. You can even examine load bearing details of how NLT panels should be assembled for floors, walls, and roofs.

Which brings me back to the LinkedIn post I read today. The U.S. Forest Service and its partners united builders, businesses, and other community members on April 24 to discuss how wood exiting national forest lands around Lake Tahoe can be milled locally to construct affordable homes and accessory dwellings. All participants engaged in the nailing of locally sourced dimensional lumber to experience first-hand the versatility of NLT. Their collective efforts will be used for the construction of a workforce housing prototype. The U.S. Forest Service Truckee Hotshots, a team of wildfire fighters, will sleep in the finished prototype once it’s erected in Hobart Mills.

Which community will follow the Lake Tahoe’s lead to showcase the power of urban wood?

Sources:

“Building Tahoe Housing from Local Wood” 27 March 2026 press release

“The Old is New Again with Laminated Timber”. Treehugger.com, 11 October 2018

“Hail to the Nail!” Think Wood®

“Nail Laminated Timber – NLT”. StructureCraft.com

“Nail-Laminated Timber (NLT)”. NaturallyWood.com

“What are the Different Types of Construction?” New England Institute of Technology

“Nail Laminated Timber: Product and Design Guide / January 2024 / Rev 1”. ABMT Wood Solutions Ltd.