The International Mass Timber Conference was held, in-person, April 12–14, at the Oregon Convention Center in Portland, Oregon, this year. This event is the largest gathering of mass timber experts in the world, so it’s a perfect opportunity for training and education.

We took particular interest in three of the multiple education tracks offered this year, Raw Materials and Supply Chains: Best Practices, Development and Construction Principles, and the Practicals of Mass Timber Design and Engineering. Some of the topics covered in these tracks were:

• Introducing and Mastering Design Topics
• Healthy Forests
• Preconstruction Planning
• Navigating Codes, Approvals, and Details
• Designing to Maximize Mass Timber’s Climate Benefits
• Modularization
• Structural Efficiency and Optimization

Participants also had the option to take a remote tour outside of the convention center walls, including:

• The expansion project of the Portland International Airport, where a seismically isolated, curved timber roof is being installed.
• A 40-home subdivision, the first of its kind that is utilizing CLT in the United States.
• The new, state-of-the-art Advanced Wood Products Laboratory at Oregon State University, where participants could see, firsthand, the cutting-edge research focusing solely on mass timber, fabrication, and construction techniques.

Three representatives from Mid-Atlantic Timberframes attended the International Mass Timber Conference, each taking their own education tracks and respective courses. It was a great opportunity to meet and learn from other likeminded mass timber professionals. Below are some of our top findings from this one-of-a-kind, informative, and beneficial conference:

Mass Timber Connection Systems

Large-scale hardware and connection suppliers are pushing hard into the mass timber market with their proprietary connection systems. However, there is also a push to develop standardized connection systems. This will be an interesting challenge since mass timber buildings themselves are nonstandard, but there is promising help from the USDA and Lendlease, who are providing joint funding to further the goal of a line of standardized connection systems.

There is also quite a bit of energy being devoted to developing a concealed connection system. While this would offer a cleaner look on a mass timber structure, there are a few challenges standing in the way of this type of connection system. One of them is how to conceal the connector without removing too large a section of timber.

Software development aimed at automated connection design is also in the works. This software would be able to automatically calculate the forces at a given joint to properly recommend the correct connection devices. The goal would be to also offer a variety of cataloged connections to select from.

CLT-Concrete Hybrid Floor Slab Construction

This type of hybrid construction is gaining traction, and there is a good reason for it. It’s possible to significantly reduce the depth of timber floor joists and girders by inducing composite action (where the two materials act together as a single unit from a structural point of view) using concrete slabs poured over CLT panels.

Mass Timber Building Codes

Navigating code requirements can be one of the biggest challenges of a mass timber project — especially in the commercial sector. The codes are there to serve as a framework, but they’re hardly “one size fits all” for these unique types of projects. It has been proven time and again that new codes can be presented and adopted for mass timber construction.

Areas of concern with respect to code adherence need to be identified and assessed early with the entire project team. It is also recommended to involve local building officials as early as possible, as your local jurisdiction might not be familiar with mass timber. Making an effort to educate them early on will go a long way toward a smoother process later in the project and also for future projects.

An interesting example of navigating code requirements was provided, a commercial project that had deep joists and girders. This created a requirement for an increased number of sprinkler heads. A code consultant developed a fire model in 3D software. The findings showed that the deep beams worked like baffles and sequestered smoke during a fire event. Thanks to this fire model analysis, the project was allowed to have significantly fewer sprinklers than had been originally required. Early involvement from a highly motivated team is imperative for an approach like this to pan out.

Moisture Management

A moisture management plan should be created during the design development and construction document phases. However, if a mass timber design-assist is not on the project team, it is unlikely that a plan will be in place during design development.

There are three types of moisture protection. The type selected is based on the assessed projected duration of exposure for a given component.

1. Repel (low robustness) $$
2. Shed (moderate robustness) $$$
3. Proof (high robustness) $$$$

Healthy Forests

Deforestation and sustainability remain hot topics. We learned a few interesting stats:

• Harvests occur on less than 2% of working forest land a year.
• Private working forests provide 73% of forests’ annual gross sequestration, 54% of total carbon storage, all while providing 90% of the harvest for forest products.
• In the United States, private forest owners are growing 43% more wood than they harvest.

The United States has been very attentive to sustainability and deforestation issues compared to other countries around the globe. The construction world has realized the benefit of regrowing more of this sustainable natural resource because they see the demand. This is positive news for the support of the future timber / mass timber market.

Residential/Single-Family Use of Mass Timber

While the commercial world has seen an extraordinary uptick in mass timber structures, demand still lags for utilizing mass timber in single-family residential construction. It’s more expensive to build with CLT and glulam compared to conventional construction, so the choice to build a single-family home with mass timber is purely for aesthetics and has a “cool” factor. Because of this, mass timber on a single-family residential scale is not likely for the foreseeable future.

Initiatives for Growth

Several initiatives, including governmental, are pervading the mass timber space, in hopes of spurring further growth:

• The Future Timber City program helps to spread best-practice information on the design, technologies, construction, and planning of mass timber buildings and larger timber communities.
• The USDA and the Forest Service are funding a Wood Innovation Grant. In 2021, half of these funded projects focused on mass timber.
• More and more large and prestigious universities are not only embracing mass timber in their curricula and studies, but they’re also pushing for new campus buildings to be constructed with mass timber.

Supply Chain Woes

The supply chain will remain an issue for quite some time. Although lumber and timber prices are expected to fall, they will continue to be higher than they have been for the past two decades. Demand is so high because:

• We are coming off a 15-year recession, and lumberyards were not prepared.
• Lumber producers and buyers reacted predictably — homeowners have not these past couple years.
• There is a lack of employees. Older employees are retiring due to the good economy, and it is difficult to find younger employees.

Some things that can help are:

• The industry investing heavily in new capacity.
• Expansion in the US South.

We have not seen the end of this pent-up demand, which will continue driving the housing market through to the next recession. That is when the industry will be able to reset and catch up.

Mass Timber Outlook

Overall, it seems the possibilities for building with timber are only increasing, not decreasing. Building with mass timber is a data-driven decision based on the performance of these structural systems, not an emotional decision or a fad. There is support for mass timber construction. Engineers and designers are not being stonewalled in jurisdictions wherever mass timber code is adopted.

We see new and innovative things on the mass timber horizon and are already looking forward to learning about them at next year’s International Mass Timber Conference. Consider saving the date, March 25–29, 2023. It will be held in Portland, Oregon, again.

If you can’t wait until next year, there’s also Advancing Mass Timber Construction 2022, a conference coming up September 12–14 at the Crowne Plaza Boston-Woburn in Woburn, Massachusetts, just outside of Boston. Its focus will be on building taller and more innovative timber structures.

In the meantime, if you have any questions about heavy timber or mass timber construction, please contact us today!