A CEGEP teacher in Rouyn-Noranda is pursuing a somewhat crazy project: 3D printing houses adapted to the climate of Quebec.

This professor is called David Laliberté. He teaches industrial maintenance at the Cégep de l’Abitibi-Témiscamingue. But, in another life, he was a factory manager. His passion is the simplification of work processes with, as a result, a better quality product.

His interest in 3D printing homes began in 2018, almost trivial, following major renovations to his new home, he says. Simple water infiltration, caused by an error during the installation of a window, had the merit of piqued his curiosity for residential construction.

Why does building a house require so many steps of sealing, then drilling for vents, plumbing, electrical outlets that still need to be sealed? wondered this trained engineer.

“In terms of industrial engineering, all these gestures equal so many risks of error,” he explains. It was from this moment that I became interested in the automated printing of buildings. This made me want to learn more and do research on the subject. »

Basically, the 3D printing of a house is carried out thanks to a concrete pump whose nozzle moves with precision horizontally and vertically. It builds the structure of the building, without the need for formwork, by laying layers of materials, often concrete, on top of each other.

Enthusiastic, David Laliberté gathered around him a team of researchers in architecture, optics, composite materials, 3D printing, passive houses and concrete structures, all active in various CEGEPs and universities in the province.

The innovative nature of the project caught the attention of Quebec, which jumped on the bandwagon with the allocation of a research fund of nearly $1 million. “All because of a leaky window,” he slips deadpan.

The goal is simple, yet defies the imagination: Completely print a modular home by March 31, 2026, with the lowest possible carbon footprint, and then donate it to Habitat for Humanity Quebec.

“A real building, built sustainably, in which real people will really live,” summarizes Mr. Laliberté.

The idea of ​​printing houses is not new. Experiments of this kind have been attempted for a few years, all over the world, underlines Professor Ammar Yahia, from the University of Sherbrooke, who did not hesitate to join David Laliberté’s team.

“We’ve been interested in 3D printing for seven or eight years,” he says in his large lab, which just happens to have a concrete jet printer.

According to this fluid concrete specialist, this emerging technology promises a small revolution in the field of construction, which is currently struggling with a labor shortage. A higher quality house could thus be built more quickly, for less, with a minimum of workers, in a safe environment and, as a bonus, a limited production of waste, he believes.

That’s not all, he continues. “3D printing opens the door to an almost infinite possibility of complex geometric shapes, previously hardly conceivable,” he explains.

In Canada, buildings were printed directly on sites in Ontario last year. But David Laliberté’s approach is diametrically different: instead of lugging the necessary machinery from site to site, he plans instead to focus on printing modules at the factory to assemble the house on the construction site.

“In Quebec, you can’t print outside all year round,” he first argues. There are also relatively long lead times to set up the printer before construction and then remove it from the job site afterwards. It is believed that factory printing can reduce these delays. »

David Laliberté and his team will try to create a house with great ecological virtues. In this regard, concrete printing weighs heavily in the environmental balance.

“It’s not the greenest material. Its production releases a lot of carbon,” acknowledges the researcher, pointing out that it is possible to use “less polluting” concrete developed at the University of Sherbrooke. But other materials currently under study could become good replacement options.

The University of Maine would have obtained interesting results with a mixture of polymers and wood resin, says David Laliberté.

The researchers also want to create a high-caliber resilient envelope, with flawless sealing and insulation. In particular, they want to develop an optical device to bring more natural heat inside the building, and thus reduce heating costs.

“Now we just have to roll up our sleeves. But we have the means for our ambitions! believes David Laliberté.