Mass Timber is the Future of Construction
Updated: Oct 27, 2022
Mass timber is a new category of wood product that can revolutionize how America builds. More and more developers are embracing mass timber as a cost-effective alternative to traditional construction materials. The material is viewed as highly sustainable and can be engineered just as strong as concrete or steel.
With $370 billion earmarked for alternative energy and climate change measures as part of the Infrastructure Investment and Jobs Act, it is expected that mass timber will be part of President Biden’s vision for the future. Alejandra Castillo, Biden’s assistant secretary of commerce for economic development, recently met with the Oregon Mass Timber Coalition and remarked, "I am excited because not only is it an industry that is very promising, it is the triangulation of the environment, workforce development and housing.”
Trade organizations such as the Carpenters Union are now offering training courses in how to work with mass timber. This is a good indication that mass timber is here to stay, and wide scale adoption is around the corner.
What is Mass Timber
Mass timber is the process of stacking and gluing small pieces of soft woods together to form larger pieces. The woods commonly used are pine, spruce, and fir but sometimes birch, ash or beech are used.
This is engineered into 5 different types of prefabricated wood: glue laminated (glulam) beams, laminated veneer lumber (LVL), dowel-laminated timber (DLT), nail laminated timber (NLT), and the most commonly used, CLT, or cross-laminated timber.
CLT lumber boards are glued atop one another in layers. Each board alternates in direction with the grain of one board running in the opposite direction of the board it is sandwiched against. Therefore, each alternating layer is situated at a right angle to adjacent layers. The end product rivals the strengths of steel and concrete and allows for the creation of slabs up to a foot thick and as large as 18 feet in length and 98 feet in width. CLT is perfect for large scale construction purposes.
Research suggests that replacing concrete and steel with mass timber will significantly reduce the production of green house gases. As it stands, construction is a huge contributor to greenhouse gas emissions- roughly 11 percent of global emissions is attributable.
A recent study at the University of Washington compared two buildings having similar functional characteristics, one built using cross laminated timber and the other constructed of reinforced concrete. The study concluded, "that an average of 26.5% reduction in the global warming potential is achieved in the hybrid CLT building compared to the concrete building."
Also, instead of materials being ordered to job sites and cut to size on site and assembled, the parts of a CLT building are manufactured in a factory using precision machinery. With detailed architectural blueprints, fabrications are exact - eliminating material waste, extra traffic, and the carbon heavy footprints intrinsic in delivery of raw supplies. Prefabricated pieces can be shipped closer to deadlines, and with more efficiency, which diminishes the need for onsite inventory.
In the past, what would have taken months with all the moving parts involved in conventional construction, can be trimmed to just weeks with substantially less labor costs involved. According to the softwood lumber board, “Mass timber buildings are roughly 25% faster to construct than concrete buildings and require 90% less construction traffic.”
Unions are Jumping on Board
Unions are betting big on mass timber. The Carpenters Union is taking initiative by offering classes in mass timber installation as part of their apprenticeships. Centers offering mass timber installer training include Elk Grove Village, IL, Kent, WA, Portland, OR, Millbury, MA, Rock Tavern, NY, Buena Park, CA, Philadelphia, PA, Richfield, OH, and New York, NY- with 5 more in development in Detroit, MI, Pleasanton, CA, Las Vegas NV, Atlanta GA and Charlotte NC.
“If Carpenters understand wood they understand how to handle it…they understand care has to be taken in order to install this properly…when we put on a training session and going through the class, they understood the process and how to do it efficiently…it’s still construction, it’s still erecting a building.. It’s just a matter of how everything goes together.” Says Craig Triplett, Assistant Director, Chicago Regional Council of Carpenters Apprentice and Training Program about their mass timber programs.
Into the Future
According to a study sponsored by the U.S. Department of Agriculture, 71% of mass timber construction is in Europe with 18% of completed or projects underway are in North America. However, this summer marked the completion (and opening of the world’s tallest) mass timber building, the 284 Ascent residential tower in Milwaukee Wisconsin. This is a sign that more developers in the United States are embracing the material as the future of construction. More and more construction projects are demonstrating the viability of building with mass timber. With the support of infrastructure money and a commitment from union labor, mass timber structures will become a standard in the years to come.