Ontario Construction News staff writer
Mass timber projects are moving from conceptual to practical and will reshape the building industry’s landscape, speakers at a Toronto panel discussion explained last Wednesday.
The Carpenters’ District Council of Ontario (CDCO) organized the event and tours of its specialized training facilities as the union anticipates rapidly increasing demand for timber construction in a diversity of residential, commercial and institutional structures.
Speakers, including representatives of a contractor, developer, structural engineer and industry supplier, described some of the opportunities and challenges as timber construction techniques expand from traditional residential single-family and low-rise markets to much more challenging and expansive opportunities.
For example, Leith Moore, founder of wood construction rental developer R-Hauz, outlined how he has started constructing mid-rise all-wood rental housing projects in Toronto, designed to fit within standard “Main Street” lot-line footprints.
Moore said the goal is to simplify the building approvals process by avoiding the need for land assemblies and rezoning for larger developments. By building six to eight-story structures on standard 40-foot lots, R-Hauz hopes to “reinvigorate the streets to create more rental assets on top of a retail or mixed use,” he said.
The idea is to create an easily-replicable template. Panels and components are constructed off-site, simplifying assembly. All building components, including, stairwells, are made from wood, using Cross-Laminated Timber (CLT). With a standardized framework, design, permitting and approvals and construction time-lines are greatly reduced, saving on costs.
Not that it has been an easy road to get to the stage of building the first pilot structure, he said. “We’ve just finished a year of piloting. And two years of approvals for pilots.”
“That was a long, life-wearying process. But one of the best days of my life was seeing those panels go up and being in a building that was warm and smelled good in the middle of winter.”
Moore said the design developed for the initial structure includes relatively large apartment units with open floor plans and elevators leading directly to individual units, but the model can be adapted. For example, non-load bearing partitions and other variations would allow for smaller rental apartments.
There is no underground parking, but some surface spaces at the rear. But parking isn’t a major issue since the R-Hauz properties are located where there is good public transit.
Earlier in the discussion, Mark Gaglione, director of Building and Material Sciences at contractor EllisDon, outlined how his organization is working on a variety of larger-scale wood building projects, also adapting off-site panelization concepts.
After Moore finished his presentation, Brock O’Donnell, technical sales representative for Rothoblaas, described how the northern-Italy headquartered business has developed an international expertise in providing fasteners and supporting materials for wooden construction.
David Moses of Moses Engineering explained the learning curve and innovation in the past decade as mass timber construction concepts evolved from leading-edge innovation to standard practices.
He said change involves innovation, transformation and education. “In my practice over the years we’ve been lucky to be involved in a lot of projects that moved the envelope and caused us to really take pause and learn,” he said. In the early going, projects required massive numbers of hours of engineering time, but as progress has been made, the ideas behind mass timber construction are moving from theory to practicality.
The “sweet spot” for mass timber right now is “going to be anywhere around eight to 12 stories,” Moses said. “And as the technology changes and evolves, and I think more of computing capacity of modelling, all of that can get transferred down” to improve design and construction efficiency.
Yet the speakers acknowledged there are still some significant hurdles for mass timber to truly become the primary construction method for more buildings.
Construction insurance, for example, remains problematic. While EllisDon has its own internal insurance brokerage and so doesn’t face some of these costs, Mark Gaglione said that mass timber construction rates exceptionally high. In recent years, “the rates were in the order of like 10 times of what we saw in the concrete world” and it was hard to find insurance even at these costs.
Insurers willing to take on wood construction projects also set very low capacity limits, perhaps $10 or $20 million maximum on a $50 million job. “So we would need to bundle up carriers together into something that’s called a subscription policy to cover a $50 million job, which eliminates any kind of competitive insurance brokering right there and then.”
Insurers simply didn’t have enough precedent for mass timber projects to price competitively, and so set rates at levels common for smaller residential structures (but scaled up in size). Rates are coming down, but are still well above what they would be for concrete construction projects.
Concerns also remain, largely with fire services, about combustion risks.
David Moses said progress is being made, with “a lot of full scale fire tests across Canada” and there are plans to build a few more full-scale one-to-two storey buildings and “invite the fire service to come and watch the fire because there’s nothing like seeing it with your own eyes to convince somebody, knowing there’s an inferno on one side of a piece of CLT and you can put your hand up against the other,” he said.
The Carpenters’ Union, meanwhile, is addressing another key issue in the expansion of mass timber – having enough skilled tradespeople ready to work effectively with the material. The CDCO invited the panel discussion audience to tour the union’s training facilities in Woodbridge, where carpenters learn how to manage large CLT beams, walls, and panels.
These specialized training programs combine with a diversity of entry-level and more advanced apprenticeship and trades training at the College of Carpenters and Allied Trades (CCAT). The training organization is rapidly growing to meet the increasing demand for new tradespeople, and overcome the looming retirement of more senior carpenters.
A CCAT instructor described the union’s increasing outreach to women and minorities, including young people from economically disadvantaged communities. Right now, about one in 10 to 12 carpenter apprentice trainees are women, he said. The numbers are not yet at the level of the general population, but are much greater than before.
Many CCAT training resources are available to non-union carpenters, because of partial government funding for the program. However, the union also offers enhanced programs to increase members’ skills, including applying Building Information Modelling (BIM) and computer skills to their work.
Union compensation – pay, benefits and pensions – make carpentry an ideal career, since carpenters can upwards of $100,000 or more a year, while they are still in their 20s.
“Where can you get opportunities like that when you are young?” the instructor asked, describing how he could afford his own own home long before others his age could have imagined possible.