3D Printing Buildings: Fire Up the Constructorbots
Quick note from Jared: This article was originally posted over on Crawford’s blog a few months ago. He sent it to me first, but as you know Shoegnome was fairly quiet this summer so I’m just now getting to sharing it. I’ve got a number of other past due guest posts to share as well in the coming weeks. Stay Tuned.
This Guest Post is by Crawford Smith
In the last
three decades, BIM tools have been changing the way buildings are conceived and designed. In a previous blog post, I described how I “drank the BIM Kool-Aid” and became a tireless (read: irritating) advocate for the adoption of BIM at the firm for which I was working at the time. I was really taken with the potential of having all of the information regarding the building centralized in one model, and could see that this was a very powerful tool. One of my enthusiastic arguments was that with BIM, the building design could one day be downloaded directly into construction robots, which would then go forth and build the building exactly as designed. I recall the reaction of one of the principals to whom I had told this: he raised a skeptical eyebrow—as if I had just reported Bigfoot hanging out in the lobby—and replied, “Don’t let any union guys hear you talking like that.” He was clearly unimpressed by my argument about the constructorbots, but was willing to give BIM a try nonetheless, which ended up being quite a good decision.
Now, thanks to 3D printing technology, the concept of taking a computer model of a building and loading it directly into fabrication machinery is a reality. Even I was surprised at how quickly my semi-facetious argument about loading a BIM model into a constructorbot has become reality.
There are a number of obvious advantages to 3D printing buildings: lower cost and construction time, less waste, less impact on the environment, and greater job site safety. The ability to cheaply and quickly create buildings also has a number of important social advantages as well. 3D printed housing could be created to provide low-income housing and emergency shelters following disasters.
Dutch Firm’s “Landscape House” to be 3D Printed
One of the first concepts for a 3D printed house was quite the opposite of low-income, however. Dutch architecture firm Universe Architects developed a design for the 5 million euro Landscape House. Based on the concept of a Möbius strip, the Landscape House is intended to blend into the landscape of the site.
The initial plan was to create all of the components of the house (except the glazing) using a large-scale 3D printer, called the D-Shape. Developed by Italian designer Enrico Dimi, the D-Shape uses the same 3D printing technology used by many commercial-grade printers, called granular binding. With this technology, a layer of sand is laid down, and a computer-controlled nozzle is used to apply a binder material in the desired shape. The unused sand is then removed, leaving the desired form, with a finish similar to sandstone. The D-Shape has already been used to create a 10-foot high pavilion, with plans to create an even larger version. Currently, I am unaware of any progress past the design stage for the Landscape House, although designer Janjaap Ruijssenaars has claimed in an interview that there are plans to “print” the Landscape House in one piece rather than assembling 3D printer-made parts. No details were provided.
3D Printing House Parts in China
In China, a firm has actually created buildings with components produced on a large-scale 3D printer. WinSun Decoration Design Engineering Company has developed a 3D printer that can create building components in a short amount of time. Unlike the D-Shape, the WinSun printer uses a technology similar to the fused filament fabrication (FFF) tech used by most desktop/hobbyist 3D printers. A movable extruder head lays down a layer of the material in the shape controlled by the design file. In this case, the material is a quick-drying combination of cement and construction waste.
The process is very quick. Recently, WinSun produced the components needed to make ten small structures in less than 24 hours. To be fair, they did not produce the components need for the roofs or glazing, and they were using four printers at the same time. Nonetheless, this was a pretty amazing feat, and the estimated cost for each structure was less than $5,000. The buildings were then subsequently assembled on an industrial site in Shanghai.
Contour Crafting: Complete 3D Printed Buildings
Taking the WinSun concept one step further is Dr. Behrokh Khoshnevis of the University of Southern California. Khoshnevis has developed a system called Contour Crafting, which would utilize a building-sized mechanism to create an entire building in situ. As with the WinSun printer, the Contour Crafting printer takes the FFF tech and scales it up even further. The device would consist of a gantry that moves across the site on rails, putting down layers of material to build up the walls and other components of the building. These rails could be extended for long stretches, allowing for the construction of multiple buildings or entire neighborhoods at once.
Khoshnevis promotes the Contour Crafting system’s ability to easily create curvilinear shapes. that would be more seismically stable than buildings with rigid linear forms. He also estimates that the cost of the building could be reduced by up to 60% due to reduced waste and labor costs. Finally, the time to build would be a fraction of what it currently is, with a 2,500 square foot house being built in approximately 20 hours.
The Contour Crafting system has the potential to use multiple types of materials. Fiber-reinforced concrete cement has been successfully employed on smaller concept-of-design machines. Other traditional materials, such as adobe, could also be used with this system.
As the WinSun system has demonstrated, there are limitations to what can effectively be “printed” at a building-sized scale—e.g. the roofs. Khoshnevis intends to overcome this issue by incorporating a robotic arm into the system which would select and place components such as wall reinforcements, joists and lintels – not unlike a pick-and-place machine used for assembling circuit boards.
This pick-and-place system would not just be limited to architectural and structural components, but would also include mechanical, electrical and plumbing systems as well. Khoshnevis envisions a high degree of mobile robotic automation that could supplement or even replace the gantry system. What Khoshnevis envisions isn’t far off at all from the joke I once made while trying to sell BIM to one of the firm’s principals.
Just as BIM revolutionized the process of building design, 3D printing has the capability of radically changing the way buildings are constructed. Individually, each one is a powerful transformative technology. Combined, BIM and 3D printing could have an incredible impact on how we produce our built environment, allowing for beautiful, safe and inexpensive housing that is unattainable with current methodologies. This is an exciting field, and merits a great deal of support. Perhaps it won’t be too long before we can finish off our BIM-based designs, download them to the on-site server, and fire up the constructorbots!
Learn more about Tesseract Design, Crawford Smith, 3D printing, and related technology on Crawford’s blog.