Opening Access -
Guilford wNLT Demonstration Building

The Guilford demonstration building is the first of its kind in the U.S. East Coast. It is constructed with welded-wood Nail Laminated Timber (wNLT ) panels. wNLT is a type of building technology that layers wood studs together using wood nail fasteners. Solid wood panel products like this are referred to as “mass timber.”

Wood nails, when driven at a high velocity into a piece of wood, create heat that burns wood lignin cells and bonds the wood nail to surrounding wood. wNLT panels can be fabricated with inexpensive automatic nailing equipment and construction skills used in the most common form of U.S. wood frame construction.

wNLT as an Alternative Technology
Wood-weld fastened Nail-Laminated Timber (wNLT) and wood dowel Laminated Timber (DLT) is attracting interest from the U.S. building construction sector. Using wood fasteners for mass timber has cost, construction, and environmental advantages compared to more mainstream mass timber products like metal nail laminated timber (NLT) and glue adhesive Cross-Laminated Timber (CLT).

1. wNLT can incorporate low-value logs from forestry operations. Wood waste utilization helps to defray the cost of managing healthy forests and protecting existing forestland from urban development pressures.

2. Where wood building demolition debris from glue adhesive and metal nail-fastened wood panels is difficult to downcycle, wood nail-fastened panels open unique opportunities for easy machining during end-of-life building recycling and downcycling chemical-free wood panels into biofuel energy feedstocks, packaging, pulp products, and compost.

3. wNLT is comparable to common metal nail NLT in terms of fabrication cost, but wNLT has lower embodied energy and fewer environmental degradation factors.

Some of the most important and often overlooked advantages of wNLT are social and cultural.

One of the most popular types of mass timber, CLT, requires higher upfront facility costs, expensive certifications (ANSI PRG 320), and scaled up production to justify the time and funds invested up front. wNLT buildings can be constructed on a small scale with inexpensive equipment by anyone familiar with light wood frame construction. wNLT has potential to support better working conditions (off-site pre-fabrication work that is closer to home and out of harsh weather) for rural, less centralized labor forces and has potential to regrow stronger region-specific building cultures and gift-economies to counter the construction monocultures that exist in the U.S.

Why are living demonstration buildings important?
Demonstration buildings are easy to understand and provide better access to alternative building materials, techniques, and practices. The Guilford demonstration building is the first building in the U.S. East Coast to use Lignoloc wood nails and driver equipment for NLT mass timber wall and roof systems. Euclid Timber Frames has used Lignoloc wNLT in Utah. However, several types of wood fastener products and panel systems are currently in development in the U.S. This work (including testing and development by the Guilford demonstration project team) is supported by institutions like the U.S. Forest Service Wood Innovations Program.

The Guilford demonstration building is a counterbalance to the rush to patent and commercialize wNLT and other wood-fastened mass timber panel technologies, fabrication equipment, and fastener types in the U.S. Sharing construction materials, knowledge, and practices freely can prioritize the growth of building cultures centered on social health and environmental protection.

Advocating for open access:
Focusing early investments on creating easy-to-understand building demonstrations, fabrication training, and user-friendly code language for building permitting is important for protecting access to newly developing, alternative building materials and technologies like wNLT fasteners and panels.

Many alternative construction practices (including environmentally and culturally sustainable traditional building technologies like adobe, cob, and strawbale as well as new technologies with potential to be patented) are not well-supported by certified testing, code language, accessible structural guidelines, and best practice manuals with user-friendly design details. For example, existing International Building Code (IBC) language does not provide specific guidance for using wood nail fasteners in mass timber buildings. Design values and code perscriptions for metal fasteners in light wood frame construction (Type V) and peg fasteners in heavy timber construction (Type IV) can be pieced together and translated into design details for a wNLT building, however, the result is likely a loss in accessibility for the general public and local builders. Anyone who wants to attain even a simple residential permit for constructing a building with wNLT would likely be advised to pay for custom engineering drawings.

PROJECT TEAM

Architect/Designer/Project Lead
Jana VanderGoot

Builders
Baybrook Remodelers
Josh Beebe Construction

Client
Dean Takahashi, Executive Director, Carbon Containment Lab

Website Design
Jana VanderGoot, 2024, using the Cargo Wireframe J587 template

Advisors
Lignoloc/Beck America: Chad Geise and Patrick Donahue

Carbon Containment Lab: Sinead Crotty, Justin Freiberg

Yale School of Architecture 2022 CC Lab Fellows:
Qian Huang, Fuad Khazam, Silas Newman, Jun Shi, Hao Wang

Eli Gould, US Representative at Quebec Wood Export Bureau

Mikhail Gershfeld, Engineer