3D Printing Will Transform Home Building – Contour Crafting

Imagine you’re having a new house built. Workers prepare the building site then a 6-metre tall crane-like gantry is brought in and installed on rails either side of the house. The machine rolls back and forth extruding fast-drying concrete and building up your house layer by layer. In 24 hours, it’s done, including conduits for electrical, plumbing and air-conditioning and the gantry is removed.

Although a relatively new development, 3D-printing technology has already been used to create successfully objects ranging from a nylon gown for Dita Von Teese to a working gun.

If used in construction, this technology known as Contour Crafting, could completely revolutionize the construction industry.

Building a 2,500-square-foot house in less than 20 hours?

It sounds like a fairy tale, but a professor at the University of Southern California Behrokh Khoshnevis says it is possible. He would toss out traditional building practices and replace them with a single 3D printer.

Contour Crafting technology has great potential for automating the construction of whole structures as well as sub-components. Using this process, a single house or a colony of houses, each with possibly a different design, may be automatically constructed in a single run, embedded in each house all the conduits for electrical, plumbing and air-conditioning.

“Construction the way it’s done today is very wasteful,” Behrokh Khoshnevis, the director of the manufacturing engineering graduate program USC,  explained in a presentation at TED (bellow).

“Our solution benefits from advanced technology…it is essentially a way of streamlining the process of construction by benefiting from the experience we have gained in the field of manufacturing.”

The 3D printer lays out concrete and interlocking steel bars as it builds a structure. Khoshnevis says that the printer can handle the plumbing, electrical networks, and flooring for multi-story buildings.

An animated video posted on ContourCrafting.org explains the building process in more detail:

“It’s a CAD/CAM solution,” says Khoshnevis. The buildings are “designed on a computer and built by a computer”. Contour Crafting hopes to create  “entire neighborhoods built at a fraction of the cost, in a fraction of the time, far more safely, and with an architectural flexibility that is unprecedented.”

The 3D Printed solution also produces much stronger structures than traditional building methods. According to Contour Crafting, the tested wall is a 10,000PSI (pounds per square inch) strength compared to an average of 3,000PSI for a conventional wall.

Khoshnevis sees the technology as a way to quickly rebuild communities and towns damaged by natural disasters.

“My true hope is that this technology gets to be used worldwide to the fullest extent possible,” he said.

Just as basic hobbyist models let designers create three-dimensional objects from bottom to top, Khoshnevis says contour crafting is working on bringing that technology to the realm of urban construction.

Khoshnevis estimated that Contour Crafting would save the construction 20 percent to 25 percent in financing and 25 percent to 30 percent in materials. The biggest savings would come in labor, where Contour Crafting would save 45 percent to 55 percent by using 3D printers instead of humans. There would also be fewer CO2 emissions and less energy used.

Their research also addresses the application of Contour Crafting in building habitats on other planets. Contour Crafting will most probably be one of the very few feasible approaches for building structures on the Moon and Mars, which are being targeted for human colonization before the end of the new century.