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Houses hot off the 3D printer
Robotic building by Contour Crafting won the grand prize in a NASA magazine's Create the Future contest.
In the not-too-distant future, building a new home may be as simple as printing it out.
The process of wielding 3D printers to make homes is in its infancy today, but someday soon you may look out your window at a large-scale printer, swiftly spitting out a whole home under the instruction of just one operator.
"Generally, they'll be much cheaper, much faster, much safer and with much nicer architectural features [than traditional homes]," says Dr. Behrokh Khoshnevis, creator of and lead researcher for Contour Crafting, one of the leading companies working on scaling 3D-printed homes for the masses.
It's really not as crazy as it sounds.
There are 3D printers making dishes, building furniture and repairing appliances right now. But a home needs a much bigger printer.
On any scale, 3D printing works like this: Someone creates a three-dimensional digital design and sends it to the printer, where it's translated into something called a "G-code" file that slices a 3D design into thin layers.
The printer also contains the building material, which in the case of large-scale printing can be plastic or cement – any sturdy material that can go from solid to liquid and back again.
The material is melted or liquefied within the printer, and layer by layer the printer follows a path until the object in the 3D digital design is completely constructed.
The layers build upon one another and solidify as they cool.
A 3D printer from the WASProject (which stands for World's Advanced Saving Project) builds walls at the Maker Fair.
Using this kind of technology for home construction may be a few years out, but it's already in use in a few select projects around the world, from an artistic, design-driven canal house in Amsterdam to a utilitarian operation that can churn out a house in just one day in China.
Still, a lot of details have to be worked out before this technology is launched on a large scale. Factors like fireproofing, insulation and waterproofing are still in testing stages for many projects.
And in most cases, no building codes regulate the materials and construction processes used to print buildings, nor are there industry standards or best practices yet that builders can rely on. Every element -- printers, software, building materials -- is evolving.
Here are some of the more notable projects.
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3D Print Canal House
The current site of 3D-Print Canal House.
When DUS Architects in Amsterdam was looking for new ways to make home design interesting, the firm decided to craft an experimental 3D printer.
They wanted to build something grand, so they selected a spot along the Buiksloterkanaal to build a traditional canal house, mimicking the iconic traditionally-built canal homes throughout the city.
The group came up with the KamerMaker (or room-builder in English). It works exactly like a small-scale 3D printer, with a digital design being translated into a G-code.
The printer moves along the designated path and spits out the material – in this case a special bioplastics granulate.
Although the technology is a work in progress, DUS has designed a house that will use the KamerMaker to print rooms using the recycled bioplastic materials. The 13 rooms will form a nearly 50-foot-high, 20-foot-wide, plastic house when they are stacked on top of each other.
Construction on the actual house began in March and is expected to last for about three years – not a quick process. But the process is a vehicle for learning, DUS says.
According to Tosja Backer, who manages the project for DUS, people started coming by to watch and offer advice before construction on the house even began. That's when the project became a "co-creation platform."
"We are a platform much more than we are just a firm building a house," Backer says.
"We don't know all the answers yet, but we now have lots of people to help us with that. The key to it is research by doing. It's really a research project. We find solutions we couldn't have found if we didn't print it."
A rendering of what DUS Architects hopes to create with its 3D Print Canal House.
In the end, Backer says, the idea is to be able to create an adequate living space fairly quickly using reusable plastics.
That way, the technology could be used to help people, particularly after disasters. In that case, the homes could be built quickly and cheaply and then melted down when they're no longer useful.
The very same plastic that was used to build those temporary homes could be used to build more homes after another disaster.
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Total Kustom's cement castle
Though not technically a home, contractor Andrey Rudenko built this DIY small castle using a 3D printer he designed.
A contractor in Shorewood, Minnesota, had an interest in 3D printers and decided to go out and design one of his own using a computer, steel rails, motors and chains.
The printer – invented by contractor Andrey Rudenko, who calls it an "extruder" – spits out a special, very viscous blend of concrete and sand.
The printer currently fits inside a two-car garage, although Rudenko is looking to make it smaller as he improves on the design.
Rudenko can program this self-made printer to print layers of concrete in patterns he designs.
Recently, he used his printer to create a large-scale, 12-foot-tall, 3D castle in his backyard, which, while technically not a home, operates on the same principles as 3D-printed homes and is the most notable example of how 3D-printed structures could become DIY projects.
The castle stands mostly on its own, but Rudenko did place steel bars throughout the structure as extra support for the cement-printed parts. He also added some tower details on top of the castle after the fact, which were printed separately and then lifted onto the main structure.
The castle was finished in late August.
Rudenko says his next project will be a two-story, 32-foot-by-50-foot, 3D-printed house.
Fine-tuning architectural features is also one of the main focuses of the 3D Print Canal House project, Backer says.
"With the technique that we use, you can create lots of different forms that you can't get when you use a cast or mold. … Different structures that we've printed, you can integrate into your design," she says. "The cool thing is you totally bridge the gap between design and production. You can make each design unique again."
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Win Sun's printed-overnight homes
A Win Sun home can be printed in 24 hours.
Arguably the project with the most real-world results is one by Win Sun, a company in China that has already printed 10 houses in Shanghai.
All 10 houses were printed in less than 24 hours at a cost of about $5,000 each.
Unlike Rudenko's castle project, Win Sun created building blocks instead of layering the base of the whole home at once. Using a cement and glass mixture in diagonally reinforced patterns, the huge printer (about 22 feet tall and 33 feet wide) can very rapidly put out these building blocks.
The company used its large-scale 3D printer in a factory, then transported the fabricated blocks to the housing site where they were assembled into actual homes.
Win Sun hopes to use the technology for cheap, fast, low-income housing. According to Runji Shen, a marketer for the Win Sun project, 3D-printed homes of the future will be constructed in weeks – and for far less money than homes cost to build now.
The company says it's in talks with several construction companies in the U.S. about potentially exporting printers and technology.
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Contour Crafting's robotic construction system
A rendering of how the Contour Crafting construction process would happen on site.
With research based at the University of Southern California, Viterbi School of Engineering professor Khoshnevis hopes to combine 3D printing with other technologies to create houses on a large scale.
He says he's within two to three years of being able to share his technology commercially. He'd also like to use his technology to create habitable environments in outer space.
The homebuilding process uses hand-held tools, robotics and rapidly-fabricated, large-scale 3D objects, according to the Contour Crafting website. In Khoshnevis' plan, workers would lay down two rails.
The printer/robot designed by his team would glide along the rails and lay cement in layers from above to build the framework of the house, based on the G-code programmed into the printer. Workers would be needed again at the end of the process to install windows and doors.
Khoshnevis says the technology would allow for a home to be built in 24 hours for far less money than traditional building methods, although the process hasn't yet been used to build a full-scale house.
He says he hopes to master a system that can spit out a home in less time than it takes now to collect materials for a building, and include better architectural features than are available using traditional building methods.
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WASP's mud houses
The WASProject 3D printer in action, building a small-scale model of the homes that the company intends to build.
An Italian firm called the WASProject (for "World's Advanced Saving Project") is hoping to use its 3D printers to fight homelessness, particularly in the wake of natural disasters, by swiftly making homes from mud.
The company would utilize a mud-extruding 3D printer, which stands 20 feet tall and can build structures as tall as 10 feet. Taking a little from Win Sun's speed and a little from Contour Crafting's scale, WASP's printer can be assembled on site by two people in a few hours. It would use materials found on site, limiting the cost drastically.
So far the company has produced the bare bones of a prototype at the Maker Faire in Rome, using a smaller printer called the Big Delta Wasp. The company plans to print a full-size home this year.
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