3D-Printing: Are You Ready?

How well will this approach to pre-fab translate to the multifamily sector?

A few months ago, Chinese company WinSun took the wraps off the first 3D-printed multifamily structure, a five-story apartment building on display at China-Singapore Suzhou Industrial Park. That unveiling has spurred questions about the 3D printing of multifamily structures in the U.S. Given the benefits of 3D printing, from time, labor and material savings to greener construction, how soon might we see the arrival of this construction technology on these shores?

Not soon enough for some observers. Yolanda Cole, principal at Hickok Cole in Washington, D.C., believes that whether it’s used in construction, manufacturing or art studio creations, 3D printing is destined to change the world.

“We are moving toward ‘mass customization,’ where you can design and manufacture exactly what you need in a short time frame,” she said. “This opens up the possibility of design solutions we have yet to imagine.”

Once 3D printing can be undertaken on a large scale—and using a variety of materials—the possibilities will likely be limitless, Cole believes.

“We could create spaces that are not tied to 90-degree corners, shaping them in exciting ways for ordinary people,” she remarked. “We could develop facades that are tailored to their specific orientation and context, design structural components to their mathematical profile [and] take pre-fab construction to a whole new level. I am truly excited about the possibilities.”

Its current cachet as a cutting-edge technology notwithstanding, 3D printing has actually been around for 30 to 40 years, said Casey Mahon, director of design technologies for Carrier Johnson + Culture, a multidisciplinary architecture, planning, branding and design firm based in San Diego, Calif.

What is comparatively new are the dramatic advances in the scale of the 3D printing machines in recent years, Mahon said. “A lot of the advances in the technology are coming from people investigating printing with materials other than extruded plastic and powder,” he reported. “The large-format printers tend to be using ceramics, such as porcelains, and/or concrete.”
The technology for printing in concrete or ceramics is based off the fused deposition model. That technology in construction uses concrete that lacks the aggregate, or the small pebbles and rocks typically mixed into concrete. The result is extrudable, and more like the grout in a masonry wall.

Technology outpacing adoption

Outside of WinSun’s multifamily construction project in China, Mahon is not aware of any entity undertaking large-format 3D printing technology in multifamily construction, or indeed any 3D-printed construction on a similar scale.

“That’s really the first project any one of us has seen where some of the research that’s been done has been tested and deployed at scale,” Mahon said.

WinSun is printing segments of cavity walls, which appear to be from 12 to 16 feet in length, and about four and a half to five feet tall, he said. Those segments are delivered to the construction site and assembled there.

The off-site printing of components is based on the fact that 3D printers, especially large ones, function better in controlled environments. “The project in China is almost akin to a pre-cast concrete strategy for construction,” Mahon said. “They are prefabricating the concrete, embedding the reinforcing members and connections required, so when on site they’re easy to stack up. Then they deploy those pieces and parts on site and simply connect them.”

As for the technology’s viability in North American multifamily construction, Mahon says the WinSun project points to the plausibility of 3D printing on a large scale. At this point, though, advancements in technology are outpacing the adoption for a number of reasons. Many have to do with regulatory factors.

It can be very difficult to adopt a new construction technology, due to the testing, inspection and certification such technologies require, he said. For adoption to occur, there must be a group of very ambitious builders, architects, developers and building engineers joining forces to push the envelope.

When 3D printing technology is adopted, pre-cast concrete contractors will likely be in the forefront. “It’s a system and process they’re already familiar with,” Mahon said. “The labor and production time savings would be very significant.

“There are risks early on adopting any emerging technology. Unexpected outcomes is one. An untested process is another. Willingness to push boundaries of what is currently accepted practice is still another.”

The offsetting benefit is interpretation of construction documents would no longer be needed. “The 3D model of the building would be the one printed,” Mahon said, adding this transformation alone would cause a sea change in the way people work. “Architects, engineers, contractors, everybody would need to readjust workflows if the technology were to become widely accepted,” he said.

Size an issue

One of the challenges that must be addressed is the size and location of the 3D printers being used. If printing enormous components of an apartment building, for instance, the printer needs to be even larger than the components.

What’s more, some of the conversation taking place around 3D printing focuses on using the technology to print entire buildings, not just components. “That kind of challenges the idea of having a printer on site, because you would need a printer larger than the entire building,” Mahon reported.

There are other size-related hurdles to overcome. For instance, the printer used by WinSun Company is 20 by 33 by 132 feet in size, he said, leading to questions about the curing time of the concrete in pieces that large.

As materials research proceeds, it is likely larger objects are going to be printed. And as the technology to print them moves forward, there will likely emerge 3D printers different from those currently being used, Mahon said.

While the WinSun project is impressive, some fairly pedestrian aspects of 3D printing have not yet been fully worked out, he added.

“The actual living conditions, how plumbing and electrical is run through the concrete walls, and things as simple as how you’re going to hang a picture are yet to be understood,” Mahon said. “Because the technology is outpacing what we’re doing in practice, it’s really exciting to see what’s possible.

“But more insight into what’s feasible is also necessary.”

As for Cole, she says she hopes to see work that is beautiful as well as functional soon. “Innovation is happening at an increasingly rapid rate,” she added. “So hold on to your seats and let’s see what happens!”