Mass Timber & Tall: What’s Driving it, and What’s Holding it Back?

27 May 2021


CTBUH CEO Antony Wood chairs the panel discussion, “Mass Timber & Tall: What’s Driving it, and What’s Holding it Back?” with panelists (top row, from left): Tim Gokhman, Director, New Land Enterprises; Lisa Podesto, Senior Business Development Manager, Lendlease; (bottom row, from left): Jeff Spiritos, Founder & Manager, Spiritos Properties LLC; and Rainier Strauch, CTO and Managing Director at CREE Buildings, CREE GmbH.

With clear benefits relating to carbon sequestration, renewability, and construction time, tall mass timber buildings are gaining traction rapidly on the global building stage. But as mass timber techniques rise to the forefront, parallel questions surface as the industry researches and considers evolving codes, standards, and expectations relating to fire safety, financial feasibility, and exactly how high tall timber can go. On 20 May 2021, a panel discussion entitled “Mass Timber & Tall: What’s Driving it, and What’s Holding it Back?” convened four tall timber experts at the 2021 CTBUH Tall + Urban Innovation Conference for a robust discussion, chaired by CTBUH CEO Antony Wood.

Wood kicked off the panel by introducing a two-year CTBUH Research Project currently underway called “Future Timber City: An Awareness and Educational Program for Tall Building Industry,” which is being jointly funded by the USDA Forest Service and the Binational Softwood Lumber Council (BSLC). As part of its objectives, the project will identify global best practices in tall timber and is currently tracking some 75 tall timber projects greater than seven stories or 25 meters in height around the world. Wood is the principal investigator of the research project, and all four panelists are members of the steering committee.

Tim Gokhman, Director, New Land Enterprises, talked about how working on Ascent—a 25-story timber-concrete composite residential building in Milwaukee—transformed his views on timber from an aesthetic choice to a material with multiple interlinked advantages, citing its shorter construction period, lighter foundation weight, and health benefits, among others. “What started as a visual inspiration turned into a conviction that this material represents the future of construction.” He then talked about how marketing new projects often includes factors related to operational sustainability, but is not always transparent about how the building is built, and how timber as a material could shift that in a significant way. “We know our industry has a huge carbon footprint,” he said. “But like Tesla, like online sales, mass timber is a disrupter,” he said.

 We know our industry has a huge carbon footprint, but like Tesla, like online sales, mass timber is a disrupter.
- Tim Gokhman, Director, New Land Enterprises

Tim Gokhman, Director, New Land Enterprises talks about developing Ascent, Milwaukee, a 25-story concrete-timber composite residential building. 

Expanding on some of the benefits of timber, Lisa Podesto, Senior Business Development Manager, Lendlease, spoke about how the development and construction firm has several long-term carbon targets, towards which it plans to use timber construction to achieve. “We’re trying to find a better way to build buildings,” she said, and spoke about how timber will help advance the company’s main objectives to improve design and construction efficiency through minimizing design cycling, compressed construction times, and predictable outcomes. “We want to be erecting buildings; not necessarily building them on-site,” she said. “How much of construction can we take off-site that can be in parallel with other aspects of design and preconstruction and really compress the overall schedule of a project?”

Jeff Spiritos, Founder & Manager, Spiritos Properties LLC, asserted that Passive House and mass timber techniques are key to a low-carbon future, which is “not optional.” “The clock is ticking. It’s our responsibility as real estate people to eliminate the 40 percent of the climate issue that comes from our work,” he said. Rainier Strauch, CTO and Managing Director at CREE Buildings, CREE GmbH, echoed Spiritos’ sense of responsibility, talking about the online infrastructure being developed by CREE Buildings to share mass timber best-practice information with the world, with the end goal of helping save non-renewable resources through all-timber, timber composite, and timber hybrid constructions. “We deeply believe in collaboration and that, only if we share our knowledge, can we create a better built environment,” he said.


Jeff Spiritos, Founder & Manager, Spiritos Properties LLC,  discusses the ways in which mass timber techniques are key to a low-carbon future.


Commercial viability was also touched on, with Gokhman citing the COVID-19 pandemic as a case study in how buildings that offer something different are superior at retaining tenants and ramping up sustained interest. “Only when we build with mass timber do people off the street approach me, and want to talk about how it’s built,” said Gokhman, regarding timber’s natural appeal to building users. Wood then asked Spiritos about the market opportunity for building timber extensions to existing buildings. “There are historic buildings that are treasures, but they don’t offer the densification we need if we’re not able to build on top of them,” said Spiritos. He also pointed out that vertically extending a building with a mass timber addition has its advantages, namely because the material is significantly lighter than steel and concrete, and because it lends itself easily to prefabrication techniques.


Lisa Podesto, Senior Business Development Manager, Lendlease explains why timber constructions are well-suited to prefabrication techniques. 


Podesto shed some light on why timber constructions are such great candidates for prefabrication. “Timber enables prefabrication for a number of reasons,” she said, citing volumetric bathroom pods and scaffold-free façades as two prefabricated elements often incorporated into Lendlease projects. “It’s a very precise medium. There’s not a lot of dimensional change in the engineered timber itself.”

Pivoting to timber composite construction and modular systems, Strauch expanded upon the CREE system, which predominately pairs timber and concrete compositely. “You need some mass in your building, for thermal reasons, vibration prevention, and deflection protection,” said Strauch. “You can combine this mass with structural performance and that’s what concrete-timber composite does well.”  


Rainier Strauch, CTO and Managing Director at CREE Buildings, CREE GmbH discusses the CREE system and its benefits to mass timber construction.


Despite its benefits, mass timber still faces some resistance, particularly to do with fire safety concerns. Wood asked what the four timber experts felt was holding mass timber back in terms of gaining more traction. “I think it’s a perception issue,” said Podesto. “The fact that you have combustible material in a building is going to give people lots of pause…but the code right now does not recognize aspects of wood that are really beneficial, for example that it can self-extinguish.” Regardless, all seemed aligned on the significance of strides in the industry. “All of these issues can be overcome with time and commitment. This is what innovation looks like,” said Gokhman.

Asked how high he thinks timber can go, Spiritos said that all we can really be sure of is that there are unknowns. “Steel and concrete tall buildings didn’t build high based on information that was known. We don’t even know how the future tall mass timber buildings will be built. Podesto offered a more affirmative response: “I think it’ll be 45 stories, residential, and in Chicago.”