We all have an idea of what's involved in building a house: great expense, a lengthy design process and an even lengthier construction process involving men wearing yellow safety helmets. But this scenario is being upended by the use of 3D printing techniques.
On building sites of the future, the traditional laying of bricks and mortar may be replaced by automated piping of layers of concrete, programmed with precision from the original architectural designs. This is no different from the process that takes place inside a desktop 3D printer – it just uses different materials, and it's a great deal bigger.
The latest example has just been unveiled by the construction technology company, Icon, at the South by Southwest Festival in Austin, Texas – a 650 square foot, one bedroom house, printed in less than a day for under $10,000.
With a global housing crisis that will, if unchecked, force about 1.6 billion people into inadequate shelter by 2025, 3D printing offers a glimpse of a solution – not least because the houses unveiled in Austin are pleasant to look at. Unlike cheaply built homes of the past, these are buildings you might actually want to live in.
Solving homelessness is a lofty ambition for a technology that most people associate with small-scale thermoplastic gizmos such as pen holders or doorstops. But 3D printing has made quiet, but significant inroads into many industries, including clothing, aviation and medicine.
The breakthroughs being made in the construction industry have raised eyebrows because of their scale. From the first printed house in Shanghai almost four years ago, to the Office Of The Future constructed at the foot of the Emirates Towers in Dubai in 2016, each announcement is met with collective amazement that construction on that scale could be automated.
"Getting [3D printing] machines of that size is difficult, so flexible robots play a big role," says Guglielmo Carra from engineering company Arup. It pioneered experiments with printing building elements in metal.
'Robots don't need to go home at the end of the day'
"But it's important to prove that new technologies can work on a large scale," he says. "You need to think about how a wall can cope with wind, or seismic activity. It also helps with public acceptance of these experiments because if people see a small-scale prototype, they then say 'OK, but now what?'"
Moving from prototype designs to actual buildings is something that 3D printing handles effortlessly. It is a simple scaling up process that can be done with total precision. That precision brings with it a raft of additional benefits, says Carra. "Reducing mistakes means reducing costs, optimising use of materials and improving sustainability," he says. "It also has huge scope in terms of freedom of shape. We've created very complex shapes in metal that you couldn't make in any other way, and which have added huge value in terms of the performance of the building."
The skill and speed with which robots are able to “print” materials, be it using concrete, metal, sand or plastic, puts them up in competition with construction workers – because they don’t need to go home at the end of the day, and you don’t need to pay them.
800 million workers to lose their jobs to robotic technology
A recent report from the McKinsey Consultancy estimates that 800 million workers will lose their jobs to robotic technology by 2030, and the construction industry will undoubtedly make a contribution. But humans will still be needed on construction sites.
"Workers are not going to be left out of construction sites," says Carra. "Robots can undertake the difficult operations and free up humans to do the less risky work. Also, not all buildings will be 3D printed. Yes, there may be a requirement for it if a building needs to be constructed quickly, or if complex shapes are needed. But 3D printing just offers more choice and more freedom to pick the best process for that specific project."
The issue of building codes
It’s been two years since UAE Vice President and Ruler of Dubai, Sheikh Mohammed bin Rashid, announced a plan to base a quarter of Dubai’s buildings on 3D printing technology by 2030, and the first 3D printed villa is due to be unveiled imminently.
More widespread use of the technique across the world, however, may initially be held back by building codes and regulations that lag behind technological change – after all, most countries don't allow you to just erect a building however you want.
Last September saw the "Bod" (Building On Demand) put up in Copenhagen, the first to comply with EU building regulations, and Carra believes that the rule books will change as the technology consolidates. "Some building codes don't specifically allow the use of 3D printing," he says. "But that doesn't mean that you can't do it. It does mean, however, that you have to go through a longer approval process."
El Salvador is one country that is offering its approval. Icon has announced that it has partnered with a homelessness charity, New Story, to construct a development of 100 of its 3D printed homes there next year.
By that point Icon hopes to have brought the unit cost of each house down to just $4,000. It almost seems too good to be true but of course rolling out new technology at such a scale is not without its problems.
“The issue of scale is one that still needs to be proved feasible,” says Carra. “And of course the technology relies on robots, which requires initial capital investment, so the economics have to be proved feasible, too.”
What is not in question is the agility of the process and the aesthetic merit of the results. “It might sound like a less relevant problem in relation to the housing crisis,” says Carra, “but this is an opportunity to bring better looking housing to certain parts of the world. Nicer environments, nicer neighbourhoods, with buildings that don’t have to look identical and can have variation without incurring extra costs.”
We already know that attractive surroundings are conducive to our well being. What we are now learning is that 3D printed buildings could, at least in theory, improve the quality of life of thousands if not millions of people.
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