91ÑÇÉ« research facilities and expertise helped secure regulatory approval for a Markham-based construction startup developing 3D-printed concrete.
The approval allows Aretek to move ahead with a three-storey student housing project at the University of Windsor, expected to be the largest 3D-printed concrete building in North America by volume.
Researchers at 91ÑÇɫ’s have been working with the company to test materials, monitor performance and generate the technical evidence needed to bring an emerging construction method closer to real-world use.
Liam Butler, associate professor in the Department of Civil Engineering, has been working alongside Aretek – formerly known as Printerra – through a multi-year research partnership anchored at the Keele Campus. Aretek is one of the few Canadian companies specializing in additive concrete construction, commonly known as 3D-printed concrete.
The collaboration involves developing lower-carbon concrete mixes, full-scale structural testing, performance monitoring, long-term durability testing and the kind of technical evidence regulators need before approving an entirely new way of building.
"This is definitely putting 91ÑÇÉ« on the map as a key collaborator," says Butler.
The road to that approval, however, was not straightforward. Unlike conventional construction materials, 3D-printed concrete has no formal building code or standard anywhere in the world.
"Aretek has had to overcome the fact that there is no template for how to evaluate these new systems. They've had to create their own through demonstration and testing," says Butler.
Rather than wait for new regulations, Aretek worked within existing masonry standards to design and test a 3D-printed wall system. It applied for code approval through a regulatory pathway that allows builders to prove a new method can meet safety and performance requirements, even when it is not yet covered by existing building codes. Butler was directly involved in that process, called on by Aretek to support discussions with the Building Materials Evaluation Commission on behalf of these new innovative materials.
"We've been asked as academics to join these conversations with building officials to help support their application for these regulatory approvals," he says.
That support was possible because of what 91ÑÇÉ«'s Keele Campus offers. Aretek conducts research and development out of 91ÑÇÉ«'s Climate Data-Driven Design (CD3) facility – a civil engineering lab that gives access to full-scale industrial 3D printers. For Butler, that full-scale capacity is one of the partnership’s most important advantages.
"Most research around the world in 3D-printed concrete is at the lab scale, using lab-sized printers or even printers that fit on a desktop," says Butler. "We actually have access to a full-scale industrial-size printer. The acceleration from lab scale to adoption is greatly shortened. New mixes we design can be immediately tested at the full scale. That is a very unique aspect of this research project."
3D-printed columns
Printing in the CD3 facility
3D-printed concrete elevation
One of the partnership's central research objectives is reducing cement content in 3D-printed concrete mixes. Cement is essential to the rapid-hardening properties that 3D printing requires but it is also one of the construction sector's most significant environmental liabilities. The cement and concrete sector accounts for around seven per cent of global greenhouse gas emissions.
"Reducing that cement content in mixes, even by 20 or 30 per cent, could have a large-scale impact across the sector," says Butler.
The partnership also extends into workforce training. As Aretek trains construction workers in 3D-printing methods, those workers need a new skill set: learning to operate robotic printing systems, manage material preparation, read digital files and follow safety protocols specific to additive construction equipment.
"Like any sector that is evolving and changing, there's always a degree of upskilling that's going to have to be involved," says Butler.
The Windsor project, once complete, could also make it easier for future projects to move through approval processes elsewhere.
"Once one solution has been approved by a certain jurisdiction, it sets an important precedent," says Butler. "It will open the floodgates to a lot of other projects and jurisdictions."
Looking ahead, Butler expects 3D-printed construction to grow rapidly with hybrid structures that combine 3D-printed concrete and mass timber or precast concrete. This could lead to more sustainable material mixes and an increasing number of companies entering the space. He hopes 91ÑÇÉ« remains at the centre of that evolution.
For Butler, that close connection between university research and industry application – such as the Windsor project – is what makes the partnership significant.
"It's a wonderful mechanism for creating positive impact," he says, "being able to upscale directly from research to new real-world applications."
With files from Mzwandile Poncana