Populations in the developing world are not only growing, but urbanizing, and this rapid migration into cities has caused housing shortages. As Habitat for Humanity reports, “around 40%—in some cases, 75%—of the population of fast-growing cities…is housed in squatter settlements without basic services.” Think of the favelas of Brazil or the shanties of Africa.
A new technology could help reverse this trend of overcrowded, unsafe housing, by producing units that have faster construction, lower costs, and sturdier materials. They are called 3D printed homes.
3D printing of physical structures happens by first designing a model on a computer. Specifications are then used to “print” the material, typically concrete, that forms walls and design attributes, placed over a pre-built foundation. As any number of Youtube videos will show, the concrete is rolled out like soft-serve ice cream, via thousands of “layers” that produce the walls, causing a rigid surface that can later be smoothed over. According to various estimates, 3D home printing is 70% cheaper than standard construction methods and can be built in 24 hours. It also offers better insulation and earthquake resistance.
The technology has slowly grown in application, with scattered examples of 3D projects in the U.S., such as a barracks being built in Bastrop, TX, by the Texas Military Department. But 3D construction hasn’t become commonplace in the West, because it faces legal hurdles and is an untested technology. Rather, it’s being viewed by a number of organizations as a way to house the global poor and is seeing early adoption in the developing world.
As Brookings Institution researchers David Kanos and Chris Heitzig observe, African cities are growing and will likely continue to do so. “Africa’s population will double between now and 2050, and two-thirds of this population increase will be absorbed by urban areas,” they write.
This strains home supply, particularly in sub-Saharan Africa: 17 million units are needed to meet demand in Nigeria and 2 million in Kenya, according to the World Bank’s International Finance Corporation, and mass production of homes is particularly challenging.
A public-private partnership between the British government and 14Trees, an affordable housing provider, has constructed two consequential 3D projects in Malawi—a home and a school. Construction of the school was completed in under a day. For homes, 14Trees can build a unit in 12 hours, while boasting a construction cost of $10,000. (The cost of building a standard home in Malawi is $19,083.)
14Trees isn’t the only firm pursuing 3D printing in Africa. General Electric’s Lagos Garage was established to provide training in advanced construction and engineering techniques, including 3D printing. Meanwhile, in Tanzania, students developed a 3D printer capable of “small-scale manufacturing.” More projects like the Malawi development could prove promising.
80% of Latin America’s population is urbanized and, according to USAID, a significant share of the 117 million people classified as impoverished live in makeshift slums, where they are subject to poor sanitation and disease. One partnership between a 3D printing construction firm and a charitable organization hopes to leverage the new technology to mass-produce badly-needed new homes.
New Story is a non-profit dedicated to improving housing in Latin America. The group’s partner, Austin, TX-based ICON, uses printers that can install foundations in a day (ICON was also the company behind the Texas military barracks). The group has undertaken projects in El Salvador, Haiti, and Bolivia as well as Mexico.
The firm, which has built at least 2,500 homes, planned to complete a 50 building complex in Mexico’s Tabasco state by late 2020, although it appears the project is still ongoing as of this month. In this region, residents earn as little as $3 per day and the homes are vulnerable to earthquakes, which 3D structures are supposed to be better at weathering. (A Purdue University research team has also experimented with its own earthquake-resistant 3D printed structure.) A recent Instagram post by New Story asserts that none of its homes in Haiti were damaged in the August earthquake.
“ICON promises that the current version of the printer will be able to provide homes for less than $4,000 in less than 24 hours once safely delivered to the destination country,” reports Pop-Up City.
While 3D-printed homes are not yet mainstream, the continued advance of this technology spells promise for the developing world. In areas of limited income, there is a benefit to having “printers” that deliver sturdy homes cheaply and quickly. Hopefully, it can become common in the developed world, too, but that has its own affordability challenges.
This article featured additional reporting from Market Urbanism Report content manager Ethan Finlan.