“3-D printing is scaling up,” writes The Wall Street Journal (April 2, 2018). All over the world, an impressive diversity of people and organizations, ranging from startups to construction and engineering firms, are successfully prototyping 3-D-printed buildings. Prototype single-family dwellings have been 3-D-printed in China, Italy, Russia—and Texas. Global infrastructure firm AECOM uses 3-D printing to prefabricate jail cells and hospital rooms.
The technology is still nascent and it isn’t about to disrupt the $10 trillion global construction market. But the technology looks like it can save energy, materials and time. CLS Architetti in Milan has just finished 3-D-printing an 1,100-square-foot, single-family dwelling, using a portable concrete 3-D printer.
Using traditional methods, El Salvador’s People Helping People has already built more than 800 homes for families who previously lived in single-room shanties made of timber and sheet metal. Currently, a cinder-block house requires about 15 days and $6,500 to build. Printing a home instead is projected to take 24 hours, cost $4,000 and use half as much iron rebar.
Fundamentally, 3-D printing with concrete is a modern update of incredibly old building technologies. Worldwide, our prehistoric ancestors made homes from mud, adobe, cob and similar materials, building up their walls one layer after another. Their structures shared many of the same advantages of modern 3-D-printing: They were strong, cheap, locally sourced and minimized waste.
While concrete is by far the most widespread architectural-scale additive-manufacturing material, it isn’t the only one. In France, a home has been printed out of both concrete and foam. Researchers elsewhere are attempting architectural-scale building with cellulose, glass and a variety of novel composite materials.
Classroom discussion questions:
- What are the advantages and disadvantages of using 3-D printing to construct buildings?
- Is this technology really going to change the construction industry?