Could This Robot Build A House In A Day?

Dr. Behrokh Khoshnevis poses by a robot-built wall.
Courtesy of Contour Crafting
By's Christine Lagorio

Building a home in one day is a feat accomplished rarely without dozens of plucky Habitat for Humanity volunteers or an entire "Extreme Makeover: Home Edition" cast. But a California academic named Behrokh Khoshnevis is sure he can do it.

Actually, he thinks a robot can do it.

Khoshnevis — an inventor, engineering professor and director of the Center for Rapid Automated Fabrication Technologies at the University of Southern California — says the idea is a simple one: "If you look around, everything else we use is made automatically, like the pen you're holding, the shoes, the cars. The reason we don't have [automated homebuilding] is simply that we haven't had the large-scale technology."

It came to him a decade ago when an earthquake damaged his house. When using a hand trowel to fill in cracks, he thought, "a machine could do this."

"Through that experience it occurred to me that I could use this simple tool, the trowel, with mechanical elements and construct things," Khoshnevis tells

For the past ten years he's been working on an idea he calls Contour Crafting, a process by which a concrete mixture-depositing bulky one-armed robot layers rows atop each other until a structure forms. The robot takes its orders from a computer, and prints the concrete onto the earth the way a printer lays down ink.

The first attention-getting building machines Khoshnevis constructed were small, table-top robots that took computer instruction to make shapes that resembled beehives, funnels or curvy vases. By 2004, he made a larger version able to build a wall.

"It attracted a lot of publicity, and a lot of people thought this was going to revolutionize the construction industry," he says. "When you build one wall, you can build four walls and have a room, and with many rooms to have a house."

Watch a robo-builder in action
Dr. Dan Boss, Associate Director of the Discovery Group at construction-supplier USG's Corporate Research and Technology Center, came across Khoshnevis's Contour Crafting at an innovation session at USG. Boss watched Khoshnevis's machine build a small freestanding structures out of concrete, and USG decided to invest in the research for Contour Crafting.

"It is very early, but I think we see that it could change how at least some buildings are done in developing parts of the world and in remote sites where you don't want to bring in a lot of outside material," Boss says.

Khoshnevis says it could bring about a more sweeping change in the construction industry.

"Eventually this technology can be used to make single-residence structures, condos or high rises," he says. "We are just at the beginning of an era in construction where full automation is going to be important."

But first, Khoshnevis must show the world he can build even one house, in one day, using a robot. He says this is the year.

By the end of summer 2007, his structure – an undulating, futuristic concrete demonstration building – should be in place at the information sciences institute at the University of California in Marina Del Rey.

"It will use curves to demonstrate the process," he says. "This technology allows you to be very flexible, and make domes and curves at the same price as linear walls."

But the house has been 10 years in the making already, and Khoshnevis has had trouble making a large-scale machine support enough weight and be precise enough to build a reliable structure.