While some researchers are pushing the 3D printing envelope by working in the unfathomably small nano-scale, University of Southern California engineer Dr. Behrokh Khoshnevis is thinking much larger.

Khoshnevis is developing a 3D printer that will be able to build houses.

It's a process Khoshnevis calls Contour Crafting, and works on the same principle as a desktop printer extruding material like ABS or PLA, only it's on a much larger scale and the printing material is concrete.

"What we are hoping for are entire neighborhoods that are dignified at a fraction of the cost, at a fraction of the (build) time, that are far safer and can be architecturally varied," Khoshnevis said.

The giant printer would work on tracks set up on opposing sides of the house's foot print with poles extending up and connected with a crossbar, on which the extruder is attached with a computer controlled gantry system.

Once it's set up, it's just a matter of putting in the print file like smaller extruder printers.

A 2,500-square-foot house could be created in about 20 hours. Not only would such a project be super convenient, it could dramatically reduce construction costs as well.

Khoshnevis hails the printer as a possible answer to the demand for low income housing needed for the 1 billion people living in substandard housing around the world.

"These slums are the breeding ground for disease, crime, illiteracy and over population," Khoshnevis said. "Naturally, governments are after solutions. They are after finding ways to change the situation. However, they are facing the problem of conventional construction. The current construction methods are being employed. They are, generally speaking, slow, they are labor intensive and inefficient. If you look around yourself, pretty much everything is made automatically today. Your shoes, your clothes … your car. The only thing we still build by hand are these buildings."

The printer could also create impromptu emergency housing in disaster areas, or even extra-terrestrial housing for lunar colonies and beyond.

Khoshnevis and his team also claim the process would be much more environmentally friendly than traditional construction methods, cutting down on the excessive use of water, energy and materials.

"Construction is a most hazardous job" Khoshnevis said. "It's more dangerous than mining and agriculture. In this country, it kills 10,000 people every year and there are about 400,000 injuries every year."

Koshnevis said the machine could open up the construction industry to many people who would normally be left out of the conventional process.

"There is a lot of concern about people being put out of construction jobs, the reality is that a lot of new jobs can be created in this sector as well," he said. "You know, women and the elderly do not have much opportunity to work in the construction industry. With new technologies like contour crafting, those people can also be employed in more creative activities of construction.