The hybrid timber tower would be the tallest building in Canada – and also one of the most sustainable. Construction uses a patent-pending, prefabricated, composite hybrid timber floor system combined with a diagrid steel structure and concrete core that slashes embodied carbon almost in half compared with a steel and concrete structure.
The building would contain 14 times as much mass timber as the current world record- holding tall wood building (Mjøstårnet, also known as the Mjøsa Tower in Brumunddal, Norway).
Dialog has joined many other Canadian architecture firms in signing a ‘2030 Challenge Pledge’ to make all buildings carbon neutral by the end of the decade.
“It’s an ambitious target and, if we’re being totally honest, a daunting one. Accounting for around 40 per cent of total global carbon emissions, the building industry is a big part of the problem,” says Dialog chair Jim Anderson.
“It can feel like a heavy weight to carry. That’s why this project has been a beacon of hope for our integrated practice – it has invigorated and energised us.”
One simple question started the entire journey: How can you build a clear span of 12 metres for a Class A office building using mass timber? Answer: The new hybrid building encases post-tensioned cables in steel cages, in a concrete trough that is then recessed into a CLT wood panel to achieve longer spans.
The architectural and engineering design team recognised early on that this innovation could help wrest mass timber out of its small-span niche, but they needed to make sure it could be constructed and be cost-competitive.
An R&D team demonstrated that not only was the system viable from a constructability standpoint, but the cost premium for the system was in line with other structural innovations.
Once the team had a proven concept, they wanted to demonstrate that it could work in any building type. That’s what spurred the idea of a super-tall structure.
“It’s six buildings that are just stacked on top of each other,” says project architect Cam Veres.
Article first appeared in Timber & Forestry E-News