This fall, the construction site of a pair of large warehouses near Kingston will look vastly different than a regular building site.
Instead of the typical dozen or so workers on site wielding tools to erect the structures, there will be just a few people – working mobile devices that control software to operate an immense 3-D-printing machine.
The printer’s human-sized nozzle methodically extrudes layer after layer of concrete to create walls. In just one pass, the printer can produce the equivalent of cladding, sheathing, thermal breaks and formwork for structure and interior finish, leaving perfect cut-outs for windows and doors (which, along with floors and roof, aren’t part of the printing process – yet).
If all goes according to plan, these warehouses will become Canada’s first 3-D-printed buildings permitted for commercial use.
Last August, the developers, Kingston-based nidus3D, printed the country’s first-ever multifamily apartment building, a fourplex in Leamington, Ont. And in December, the company printed the first two-storey structure in North America, a house on Wolfe Island, also near Kingston.
Those two residential projects are relatively narrow because the printable area of nidus3D’s gantry-style 3-D concrete printer stretches just 40 feet. The upcoming warehouse development will inaugurate a nidus3D-pioneered system that uses site-printed wall sections that will be fitted together by crane – allowing the company to print buildings that are much larger than the printer.
The company says 3-D-printed structures can be built quickly – the ground floor of the Wolfe Island house went up in two weeks – using less materials and producing virtually zero waste, such as off-cuts, to deliver sustainable, highly insulated, airtight and energy-efficient buildings.
For now, costs are equivalent to typical masonry structures, but it aims to become more affordable as it scales up, with more printers expected to be delivered to Toronto and Vancouver by next year.
“We do anticipate costs dropping dramatically,” says Ian Arthur, nidus3D’s president and founder, and until recently, Kingston’s NDP MPP. “We think that, within a couple of years, it will be the most affordable means of putting up a building.”
According to a 2018 study in the U.K. research publication IOP Science: Materials Science and Engineering, 3-D printing can cut costs by at least 35 per cent compared with current manual costs.
Mr. Arthur says his one-term political career spurred an entrepreneurial interest in solving housing affordability and some of the mounting issues challenging the construction industry.
“It’s a sector in nothing short of a crisis,” he says. “It’s facing pressures from so many different directions.”
In addition to material-cost and supply volatility, “we have a huge labour crisis across the country, and as the boomer generation retires, this labour pinch is only going to get worse.”
”We have a huge labour crisis across the country and as the boomer generation retires, this labour pinch is only going to get worse.— Ian Arthur, president of nidus3D
Statistics Canada’s latest report records an all-time high job vacancy rate in the construction sector of 7.7 per cent, with employers seeking to fill 81,500 vacant positions.
Citing BuildForce, it says the industry needs to recruit 309,000 new construction workers over the next decade, driven predominantly by the expected retirement of 259,100 workers.
Meanwhile, the Canada Mortgage and Housing Corporation (CMHC) estimates that to meet affordable housing requirements, the country needs to substantially increase the number of homes projected to be produced by 2030 – from 2.3 million units to 3.5 million. The biggest housing supply gap is in Ontario and B.C., where housing is least affordable, according to the CMHC.
Unless the industry “starts solving how to build in a different way” that requires fewer workers, Mr. Arthur says, it is unlikely to meet the country’s housing demands.
“We build homes with hundreds of materials, thousands of components and, honestly, millions of steps to get a building out of the ground,” he says. “3-D construction printing simplifies the process and automates it,” making it substantially less labour-intensive, Mr. Arthur says, adding that nidus3D’s construction printers will eventually be run by just two people.
Another company goal is to print with an eco-friendly concrete alternative, “such as wood fibre with a binding agent,” he says. “We have research partnerships with universities, so over the winter we’re looking to print a lot of samples.”
Even if nidus3D succeeds at lowering costs and emissions, the question remains whether Canadian lenders and investors will be quick to embrace 3-D-printed buildings.
“Quick is never a word that’s used in Canada when it comes to banks,” says Marlon Bray, senior director at Altus Group. “The Canadian environment is a lot more risk- averse, a lot more cautious, than other countries.”
The international real estate industry has slowly started to warm to 3-D-printed buildings, a product Mr. Bray describes as “extremely niche.” China, an early adopter, boasts the world’s tallest 3-D-printed structure, a five-storey apartment building, while a 6,900-square-foot municipal building in Dubai is the world’s largest, according to ArchDaily.
In the U.S., last year construction firm SQ4D sold what it claims was the country’s first 3-D-printed home, in Riverhead, N.Y., for US$299,000 ($403,000).
U.S. construction company Icon is at the forefront of the country’s 3-D printing and is currently printing a 100-home community in Texas designed by Bjarke Ingels Group. In December, the partners were awarded a US$57-million NASA contract to develop a livable, 3-D-printed lunar base on the moon’s surface.
Mr. Bray says advances in construction automation, such as 3-D printing and robotically manufactured modular structures, will be part of Canada’s future, but it might take “at least a decade” to reach critical mass.
“The entire capacity for robotics in construction right now is about 2 to 3 per cent of the whole North American market: A tiny, tiny bit,” Mr. Bray says. “And while I think it’s a huge part of the future, it’s a mid- to long-term time range.”
Prefabricated buildings are further along than 3-D-printed ones, he says, “but could even modular apartments ramp up in two or three years? No. The technology needs significant investment.”
And that usually takes many, many years, he says.
“If you look at the car, it took 13 years for it to replace the horse,” he points out.
author: NANCY LANTHIER originally published here 11 January 2023