Canada is on the cusp of a great leap in the use of 3D printing for housing, growing from a seed planted in a four-unit Leamington affordable housing project finished in 2022.

Based on knowledge gained from that first-in-Canada effort, the industry is preparing to scale up to levels that will make 3D printing much cheaper and faster than traditional housing, says the president of nidus3D, which provided the equipment and labour for the Leamington build.

“We learned a ton,” said Ian Arthur. “It was the first time we really had an opportunity to collect data related to a real job.”

3D printing is a process for making three-dimensional objects from a digital file. In the case of housing, concrete is applied in layers to form a shape according to instructions in the digital file.

Arthur said nidus3D is now in talks for projects with about five times more units than the four, 560-square foot, units in Leamington. The larger the projects, the cheaper the price per unit because of the significant upfront costs associated with the printer and the ability to rapidly repeat each structure.

“To be successful, we need to go from four units to approximately 20 units. And then we need to go up to somewhere between 60 and 100. That is where this technology shines. And that is where we become, I believe, the most cost-effective means of construction out there.”

“It’s just like renting an excavator, except you’re renting a printer,” added Fiona Coughlin, Executive Director and CEO of Habitat for Humanity WindsorEssex, which acted as the builder for the Leamington project. “If I’m renting an excavator for four houses, instead of one, it’s going to cost less per house.”

Arthur said Canada is about five years behind the United States and Europe, where the technology has received more government support. He pointed to the 100-unit, 3D-printed, residential community of homes near Austin, Texas being built by the ICON 3D printing company and Lennar Homebuilders. It offers three- and four-bedroom homes ranging from 1,574 to 2,112 square feet. Sales started last year, with prices ranging from $475,000 to $599,000.

“I think the ICON-Lennar build is incredibly important,” he said. “It’s the first time that we’ve seen a large-scale builder start to deploy this technology.”

Arthur also referenced Europe’s largest 3D printed building, the 600 m2 (6,600-sqare-foot) Wave House data center in Heidelberg, Germany, which was completed earlier this year in just 140 hours.

Dr. Sreekanta Das is a professor in the Civil and Environmental Engineering Dept at the University of Windsor, where he is also Associate Dean, Research and Graduate StudiesDas, who had been researching both modular and 3D printed housing for several years, was the academic muscle behind the Leamington project.  

He said a 3D printed house should cost about 30 per cent less than a traditional house. But he’s also excited about the speed of construction.

“It took about 10 working days to print the house which includes all walls, beams, and columns. We then used traditional methods to finish the roof, windows, doors and HVAC system, which 3D printing cannot do yet,” he said. “No other technology can beat that in terms of speed.”

“If you want to build houses very fast, especially for low-income people or in remote areas, northern communities, it’s best because it needs only 3 to 4 people to run. “So that is a perfect technology for building homes to take the homeless people off the street.”

Couglin, who said she has had calls from several other Habitat for Humanity affiliates interested in 3D printed houses, added another advantage: durability.

“These houses will stand the test of time,” she said. “And I think that’s a really interesting finding, that was maybe unexpected. People really focused on how fast and how cheap. But I think the durability is actually a really key component to these builds. That, I think, is a game changer.”

Finally, with more than a year of occupancy, it can be said that the tenants also like the product, says Krista Rempel, executive director of The Bridge Youth Resource Centre, which provided the land and inherited the buildings.

“From our perspective, and a tenancy perspective, we’ve had really good feedback. It’s a really interesting look and feel, very industrial look, aesthetically pleasing.”

Das is now working on a building code for 3D printed homes. The lack of such a code made the construction of the Leamington project more difficult and it needs to be addressed for the industry to flourish in Canada.

He is also lobbying for better training for construction workers so they can work on 3D printed homes. With 3D, he said, they need to be skilled with a computer, instead of a hammer.

See: Canada’s first 3D printed multi-unit homes – Part 1 of 3 (placetocallhome.ca)