Toronto design firm DIALOG is seeking a patent for its design of a hybrid mass timber, net-zero carbon high-rise tower that could reach up to 105 storeys. (Courtesy DIALOG)

DIALOG, a leading global design firm based in Toronto, has developed a prototype design that could see hybrid mass timber high-rise towers sprouting in major cities and rising up to 105 storeys.

The patent-pending design – which would utilize a mix of sustainable mass timber, steel, and concrete in its construction – will also create a zero-carbon tower to address the growing concerns about greenhouse gas emissions and climate change.

Architect and principal Craig Applegath said DIALOG has been working on the idea for the past couple of years.

“It is zero-carbon which means that operationally it does not produce any emissions from its operations. Most buildings produce carbon emissions because they have gas-fired boilers and they have electricity that comes from the grid and the grid has a certain amount of carbon in it.

“So, just operating the building itself creates carbon. This is a building that creates no net carbon out.”

Canadian-designed algae bioreactor

Applegath said the building design is “super-innovative” and employs two sustainable systems to provide energy for its operations.

First, photovoltaics would be deployed on the east, south and west façades. As the sun moves around the building, energy is absorbed from the sun and turned into electricity.

The second is the use of a Canadian-invented algae bioreactor to suck the carbon out of the boiler and the co-generation plant.

“Under this building, there’s a co-heat and power gas-fired generator. The emissions from that  . . . get pumped into these big huge tanks filled with water and high-intensity LED light and algae,” Applegath explained.

“Algae grow like stink and they eat all of the CO2 and the nitrous oxides and sulfur oxides.

“That algae is valuable. That can be used literally to feed animals, or remediate soil, or it can just be burned again.”

The system was created by Pond Technologies in Markham, just north of Toronto. “We knew about that because I knew the CEO and I thought ‘this stuff is going to save the world’.”

A hybrid mass timber super-tall tower

A super-tall building is a definition in tall-building parlance. The Council of Tall Buildings and Urban Habitat (CTBUH) has defined super tall as anything standing more than 300 metres (just under 1,000 feet) in height.

The prototype design by DIALOG is for a building that is 460 metres (1,509 feet) tall. The net building area inside is about 115,820 square metres, or just over 1.2 million square feet.

DIALOG has offices in Toronto, Vancouver, Calgary and Edmonton, as well as an office in San Francisco.

“We’ve got architects, engineers, interior designers, landscape architects. We’re an integrated practice. We were sitting around at a retreat a couple of years ago and we said, ‘you know what, there’s a lot of cool technologies we’re dealing with in our different spheres. We need to bring these together in a way that can demonstrate the best way to create a zero carbon building,’ ” Applegath said.

“The editor of the CTBUH Journal, that asked us to write an article (on marrying the new design with the clean energy technology), said no one in the world has done this before as far as they can tell.”

DIALOG system creates open floorplates

Craig Applegath is an architect and principal with DIALOG. (Courtesy DIALOG)

Then there is the design of the building itself, which incorporates DIALOG’s prototype Hybrid Timber Floor System (HTFS). The HTFS is created via a unique combination of sustainably harvested timber, steel and concrete.

The system is designed to construct hybrid wood buildings with fewer support beams, resulting in more spacious floorplates which can be built to much greater heights. The result will be cleaner, elegant towers which will fight pollution rather than cause it, according to DIALOG.

The wood component of the flooring incorporates cross-laminated timber, a wood panel product made by gluing together layers of solid-sawn lumber.

Other structural aspects of the tower would be constructed in traditional fashion, employing a steel frame, Applegath said.

DIALOG is now seeking a partner to create its first development utilizing the systems.

“We want to get this out to the world that this is possible,” said Applegath. “We’re going to look for a development partner. Around the world, there are development partners that are looking to do super tall buildings.”

The company’s promotional material states global carbon emissions must be reduced 45 per cent by 2030 to avoid the worst effects of climate change. It says buildings and construction currently account for about 39 per cent of energy-related emissions.

“A number of us have become, in the last few years, sort of proponents and experts in mass timber. We’re passionate about mass timber,” Applegath said. “We thought, ‘We have to bring these two things together’.”

And, if they’re going to create a zero-carbon, hybrid mass timber tower, they want to make a statement.

“We said we can’t just have any old building: what we need is a building that really demonstrates how far you can push the limits reasonably. So we said let’s do a super-tall.”