A Texas construction technology company says it has developed a 3D printer that will be used later this year to build a cluster of houses in an impoverished Latin American community as the experimental equipment graduates to real-world use.

The project will pair the Austin-based company ICON with a California nonprofit called New Story that has been building houses in the region for the last several years. ICON will roll out its Vulcan II printer for the project, an updated version of a printer that was unveiled last year in Austin where it printed a single-story house in a couple of days.

Since then, ICON has been tweaking the design and now says it can create the walls of a house in a day or less, according to an article posted by Fast Company. Wiring, plumbing, windows, doors, the roof, and other details all would be left for crews using conventional techniques. ICON regards 3D printing as the most promising technology for building affordable and durable housing in distressed areas.

In addition to taking on the Latin American project, ICON says it plans to ship Vulcan II printers to a small group of customers this year while it actively seeks orders for 2020. Fast Company didn’t offer details, and ICON declined in an email to answer any questions.

How the printing process works

According to information posted at ICON’s website, the gantry-style printer is capable of printing walls that are 8-1/2 ft. tall and up to 28 ft. wide (the length of the building is, in theory, unlimited). A computer-guided nozzle dispenses a 1-in.-tall, 2-in.-wide bead of a proprietary cement-based material that cures to form finished walls.

The printing material, called Lavacrete, is mixed and pumped from equipment housed in a trailer. The 3,000-lb. printer uses 2 gal. of water per minute and can lay between 5 in. and 7 in. of material per second. It requires a crew of four to six people to operate.

ICON says 3D printing has many advantages over conventional construction, including faster builds, near-zero waste, and less reliance on manual labor. Concrete is a well-understood and affordable material, the company adds, and printed walls combine structure, interior and exterior sheathing, a moisture barrier, and insulation into one.

Although the company says the high thermal mass of printed walls are advantages for comfort and energy efficiency, the R-value of a completed wall isn’t listed. Given the low thermal resistance of concrete in general, it’s not clear whether these printed houses would be suitable for anything other than very mild climates where freezing temperatures aren’t a concern. If additional insulation would be added for some climates, the company doesn’t explain how that would be done.

The Latin American project is a mystery

Fast Company writes that New Story was frustrated at the slow pace of reconstruction in Haiti after a major earthquake there in 2010. The nonprofit thought that rebuilding with conventional construction techniques would be too slow, so it began working with ICON on the development of the printer.

New Story originally said the printer would be used to make dozens of houses in rural El Salvador this year. The houses could be created in a single day for about $4000, much less than the $6500 that New Story was spending to build simple houses with concrete walls, according to an article published last year.

But a variety of factors, including access to land, permitting, and utilities, prompted the nonprofit to move operations to another part of Latin America. Where, exactly? New Story won’t say, because “intense interest that the technology generates could undermine completion of the project,” Fast Company reported.

New Story’s website says the houses will be between 600 sq. ft. and 800 sq. ft., and that in the future it would share the technology with other nonprofits and governments that are focused on providing housing for underserved families.

In an email, New Story declined to answer questions about the project.

Printing houses is becoming more common

Icon is by no means alone in developing the technology for printing full-scale houses. In an article posted at ALL3DP, an industry newsletter, Leo Greguric mentions four examples (including the Austin house produced by ICON). They range from a 410-sq.-ft. house built by a Russian company for $10,150 to an office building in Dubai that took 17 days to print at a cost of about $140,000.

The Chinese company WinSun says it built 10 small houses in just 24 hours in 2014, and later went on to fabricate a three-story villa that could be printed in a month at a cost of $160,000.

In 2014, a Minnesota man named Andrey Rudenko printed a small castle with a gantry-style printer he designed. Rudenko’s website shows a variety of buildings made with a printer, and he will sell you a printer of your own for as little as $300,000. It’s capable of printing a house measuring 10 meters by 15 meters (33 ft. by 49 ft.), according to his website.

Although it’s difficult to generalize about costs, Greguric writes, it’s possible to print a house for as little as $4000, a price that would include the roof.

“As time progresses, more and more companies will adopt 3D printed buildings,” he says. “This, combined with developing technologies, will bring prices down and quality up. And that’s great news if it means more access to safe, affordable shelter for those in need.”