A Virginia woman and her son recently made history when they moved into the world's first owner-occupied 3D-printed home, taking the nascent technology out of the lab and into a local neighborhood. That project, a collaboration between Habitat for Humanity and Alquist, is an interesting development for the construction category, which in 2019 had a global market share that stood at just $4 million but is projected to grow to $1.8 billion by 2029.

Developments in artificial intelligence (AI) and robotics—including construction 3D printing, also called c3Dp or 3DCP—could address inventory and affordability challenges and materials and labor shortages while having a positive impact on sustainability and equity. But the purported benefits of implementing this technology on a large-scale basis remain unclear due to current logistical challenges and limitations. What are the potential benefits and barriers of 3D-printed homes, what needs to happen for them to become a viable option in the housing ecosystem, and what can the industry expect and anticipate from this emerging trend?

3D-Printed Construction Touts a Short History—But a Long List of Potential Benefits

A 3D-printed house is built via a process called additive construction, which uses various hardware and software components to create and fuse together walls and other parts. One of the most common methods currently uses a robotic arm that extrudes a concrete mixture layer by layer.

3D-printed home construction dates to 2004 when a professor at the University of South Carolina attempted to print a wall. In the past few years, however, innovation has progressed rapidly. In 2018, the first 3D-printed home in the U.S. was unveiled at SXSW, and in 2020, Austin-based developer ICON created its first 3D-printed homes as part of a community for people experiencing homelessness. On the heels of that project, ICON unveiled last year the largest 3D-printed structure in North America, a 3,800-square-foot military barracks in Texas. Today you can peruse 3D-printed homes for rent on Airbnb in British Columbia and San Diego, and an increasing number of global construction companies use this process.

Although in the beginning stages for home construction, 3D printing can offer several potential benefits.

It can meet the growing demand among buyers for homes that are sustainable, resilient, accessible, and energy-efficient that use smart technology, while creating the opportunity to incorporate these features more intentionally and efficiently. Experts at Habitat for Humanity, Alquist and the Virginia Center for Housing Research cite other upsides including:

  • Addressing lack of affordable supply: If 3D printing can be effectively scaled, streamlined, and standardized, it could be a useful tool in increasing the number of affordable homes that can be built each year.
  • Minimizing required resources: 3D printing with concrete can alleviate specific pain points as it requires significantly fewer materials, including siding. Furthermore, less dependency on the variable availability of resources equates to more control in the process.
  • Faster construction: 3D-printed walls can be built in hours instead of weeks, with a smaller crew of workers. (Workforce development programs are encouraged to replace lost framing jobs.)
  • Lower price point: These dwellings can cost around 15% less to build than stick-built homes; they aim for savings of 30% within the next two years.
  • Energy-efficiency: A concrete 3D-printed home’s double-wall cavity system is very well insulated; Alquist says their houses require half as much energy to heat and cool as a traditional stick-built home. Raspberry Pi technology embedded in the walls can sense air quality, temperature, humidity, vibration, sound flames and gases, while an electric vehicle charger can be installed in any abode.
  • Homeowner input and maintenance: Buyers can choose between ribbed or smooth exterior or interior walls, and materials in the open market including paint can adhere to them. A 3D-polymer printer and digital files allow owners to easily print replacements like doorknobs, cabinet pulls and light receptacles.
  • Out-of-the-box solution: Household formations today are different than in previous generations, as millennials are delaying marriage and children, multiple generations are living together, and people are even jointly buying houses with siblings or friends. 3D-printed homes can be easily customized to accommodate these and other scenarios.

Just Press Print? Not So Fast.

Despite some of the attractive attributes inherent in using 3D printing for home construction, the innovation is not without its limitations or obstacles. To begin with, the equipment is expensive and difficult to ship, and once onsite it takes a day or two to set up and calibrate—factors that can be mitigated by printing multiple homes in one trip, like in a housing development. The printer’s unwieldy footprint makes it unfeasible for high-density urban areas, while glitches in hardware, software and firmware need to be solved. Right now, zoning code challenges exist, 3D printing is more cost effective for attached or semi-detached homes than it is for fully detached single family units, and the structural viability for two-story dwellings has not yet been established.

But the biggest single factor impacting more mainstream use of 3D-printed construction is weather.

For the process of concrete extrusion, the temperature should be between 60- and 80-degrees Fahrenheit, and absolutely cannot be below 40 degrees or above 95 degrees. Printing can proceed during light but not heavy rain, and it shouldn’t be attempted during high winds. Once constructed, it remains to be seen how a 3D-printed home will withstand major weather events including hurricanes, tornadoes, floods, earthquakes, and fires.

What’s Ahead for 3D-Printing 2.0?

Despite the barriers that need to be addressed, there are some developments on the horizon that may help to make 3D-printed homes an affordable, appealing option for more American homebuyers. At some point in the future, it may be possible to go to your neighborhood home improvement store, view accessories and replacements for your 3D-printed home, use a QR code to purchase relevant files, and take them home to print them on demand. In the shorter term, experts foresee:

  • Materials like hemp and clay used for printing, since they are more sustainable than high carbon-cement—a required component in concrete aggregate. Mighty Buildings is also experimenting with Corian, a synthetic stone that hardens upon extrusion—but it’s expensive.
  • Design developments that enable wall surfaces to resemble wood, stucco, or stone.
  • Solar panels installed into roofs, adding to homes’ sustainability and energy-efficiency. This retrofit will soon be added to the Virginia home, which is also EarthCraft-certified.

It remains to be seen exactly how much of an impact 3D-printing construction will have on the housing industry. Freddie Mac is watching with a close eye on technologies and trends such as 3D printing that could affect the housing ecosystem and our efforts to promote affordable, energy-efficient, equitable housing for all Americans.