3-D printing is going mainstream. It’s already become an incredibly useful tool for rapid prototyping in the manufacturing world, and now it’s moving into the world of buildings.
A handful of inspired architects and engineers across the globe have been seriously geeking out 3-D printing over the past several years. And they’re painting exciting visions of how entire buildings or their constituent parts can be made, today and in the future.
In the world of manufacturing, many have touted industrial 3-D printing as an inherently green technology. Deeper studies have however questioned and debunked a lot of those claims. Ecological fails–toxicity, exorbitant energy use, and wasteful use of materials–have been found, counterintuitively, to outweigh some of the oft-touted wins like reduced transportation impacts, recyclability, and biodegradability.
With compelling applications of 3-D printing bubbling up to the architectural scale, should the environmental alarm bells be going off like they are in the world of manufacturing?
Earlier this year DUS Architects began the long, expensive process of printing–room by room–a whole house in Amsterdam. Billed as an interactive research project, the 3D Print Canal House uses mostly bio-based plastic, an enigmatic secret sauce engineered by the world’s largest adhesive manufacturer, Henkel (the makers of super glue).
While they won’t discuss the actual material composition, DUS proclaims that their 3-D printed parts produce zero waste, reduce transportation impacts, and are fully recyclable. These perceived benefits seem to echo some of the flimsy assertions orbiting industrial additive manufacturing.
Sourcing materials that are natural, non-toxic, and recyclable is commendable. But melting plastic uses lots of electricity. Research has found that for industrial 3-D printers the bulk of impacts are linked with the amount of energy they use, which outweighs benefits like lower transportation impacts and recyclability. Choices for materials shouldn’t be ignored. It’s just that in the big picture, their importance is overshadowed by the need to find much less energy intensive ways to print.
One promising approach is to not melt materials at all. Instead, it’s possible to use binding agents alongside substances reclaimed from the waste stream. That’s exactly what Ron Rael, an architect and professor at UC Berkeley, is up to. His design agency, Emerging Objects, is experimenting with new materials and methods of organic form-making for modular architectural elements. Rael’s vision is to one day scale up to an entire building.
He’s reluctant to boast the environmental advantages of his work, since emerging research portrays 3-D printing as anything but sustainable. Given that, he makes durability and affordability his primary research and development goals, along with reclaiming materials that would otherwise end up in a landfill.
Using an eclectic palette of cement, recycled sawdust, pulverized tires, paper, and even salt, Rael’s work has a distinct lightness to it, an aesthetic supported by advanced digital modeling and computation tools. Making porous, perforated walls isn’t just interesting visually. It allows him to use less material and less energy to create a monolithic object with the same function.
While low-cost solutions are Rael’s target, don’t expect to nab an Emerging Object creation today at a discount price. For now, at least, they’re admittedly at the higher end of most construction project budgets.
That’s not to say 3-D printing building components can’t be done economically, if recent news from a Chinese company called WinSun proves accurate. Like Rael, they’re printing individual components that are assembled into fuller, habitable structures. But in this case 10 2,000-square-foot homes can be fabricated in a single day, at $5,000 a piece, making it a particularly promising advancement for populations facing extreme poverty or displacement in the developing world.
There’s nothing particularly “green” about WinSun’s materials. Concrete, which uses cement for structural binding, generally has a high energy and environmental footprint. But these concerns likely take a back seat to the social benefits of cheap and rapidly deployable shelter for people in desperate need of housing.
USC Professor Berok Khoshnevis also has plans to apply a 3-D printing technology to help impoverished populations improve their living conditions. Rather than fabricating individual components for later assembly, Khoshnevis’s company Contour Crafting aims to literally print a building from the ground up. His automated construction technique uses robotic arms and a gantry system to deposit concrete through a nozzle. With continued development, he foresees a spacious dwelling being built in as quick as one day.
Khoshnevis is bullish about the ecological benefits of his approach. In a comparative life cycle assessment study, he found the environmental impact of Contour Crafting’s technique to be much lower than traditional concrete masonry construction methods. But he’s quick to qualify that without a deeper and more rigorous study, making absolute judgments on Contour Crafting’s greenness is premature.
That kind of cautious optimism is appropriate, especially considering the history of similar ambitious–and frequently unfounded–claims for industrial 3-D printing. In all of the examples discussed here, there’s just not enough data yet to make a call on whether or not 3-D printed buildings, in any of their many forms, has environmental excellence bragging rights.
And for now, that’s okay. The sky is not falling. These pioneers will continue refining their craft in the coming years, hopefully with a determination to rigorously quantify, communicate, and improve their aggregate benefits to the planet they aim to serve.