Additive manufacturing represents a compelling, if uncertain, approach to building construction. Employed by computationally savvy design firms and manufacturers, the method has enabled a generation of intriguing building blocks and assemblies. Yet many questions remain about its fundamental application advantages, as well as how the process may be used as a vehicle for conceptual inquiry. Implemented by design firms primarily in the form of 3D printing, additive manufacturing requires the combination of compatible software, hardware, and material feedstock. Architects and designers who pursue this approach are exploring the interrelationships between computational modeling and material research, seeking meaningful ways through which to bridge the gaps between the virtual and physical realms.
Two practices that typify this effort—Emerging Objects and Smith|Allen Studio—represent promising avenues for the integration of additive manufacturing via 3D printing in architecture, each with its own unique set of aspirations and challenges.
Both firms consider materials to be the primary driver of their work, but each emphasizes different aspects of the related research. Oakland, Calif.–based sculptor Stephanie Smith and her Smith|Allen co-founder Bryan Allen focus on a subset of 3D-printed materials, which has allowed them to create tools, details, and methodologies for manipulating specific material attributes. By concentrating primarily on polymers—such as photopolymer resin or PLA bioplastic—the designers have accrued important knowledge about materials that are not commonly used as building blocks in architecture, but still have advantageous properties. Smith and Allen shape their design process around granular problems like how individual components are stacked, as well as holistic concepts about the entire assembly. They continually revise their design process based on balancing often conflicting goals. “The major challenge for us is finding forms and details that are architecturally, formally, and spatially interesting while still being able to be rapidly constructed, affordable, and fabricated within the limits of existing 3D printers,” Smith says.
For Emerging Objects co-founders Ronald Rael, AIA, and Virginia San Fratello, AIA, also based in Oakland, material provenance is the primary concern. The architects initiate each project by asking questions such as “Where does a material come from?”, “What are the implications of its origins?”, and “What is the material's future trajectory?” Emerging Objects experiments with a wider range of materials than Smith|Allen, including many of the firm’s own invention, hence its prioritization of material origin.
Rael and San Fratello’s palette is largely derived from raw material sources. Some materials like nylon or acrylic are common in additive manufacturing processes, but others—such as salt, sawdust, chocolate, and a proprietary cement polymer—are among the more novel ingredients used by the firm. In one example, the architects have created multifaceted building blocks and web-like trays using century-old salt harvested from crystallized ponds in Redwood City, Calif. (Which comes from later stages of the brine-boiling process shown in the photo above.) According to Rael and San Fratello, these modules are not only durable, but also translucent and waterproof. Other objects are made from 3D-printed sawdust, composed of recycled hard and soft woods, with optional fiber reinforcing for added strength. The material is similar to wood in that it exhibits a grain based on the depositions created by the printing process, yet it is inherently translucent and isotropic.
For Smith|Allen, material selection is based on the intended application. Unlike Emerging Objects, the firm uses readily available materials. “We go to great lengths to try to use off-the-shelf materials as much as possible,” Smith says. But because these materials are not usually associated with full-scale construction, their use in such applications is still inherently novel, albeit easy to source en masse.
Since scalability is a fundamental objective, the designers are often challenged by size-related constraints. “Since we are using so much more material than a normal 3D printing user, we tend to run into the limitations of how small the 3D printing world still is,” Smith says. “There’s a huge difference between running through a couple spools of filament in an office while prototyping to running through hundreds of rolls in tens of thousands of hours of print time.” Echoviren, a 10-foot by 10-foot by 8-foot bio-plastic construction that the firm claims to be the world’s first 3D-printed, full-scale architectural installation, exemplifies such an approach.
Although many of their projects are made using a single medium, Smith and Allen have begun to incorporate multiple materials, as well as interactive elements and lighting systems, into their constructions. This approach has required the pair to understand how 3D-printed components can interface with other materials. An example project is Liminal Mass, an interior ceiling installation in a house in Bolinas, Calif. The suspended surface, which measures 51 inches wide by 91 inches long, is made of 3D-printed bioplastic modules attached to a water jet–cut aluminum frame. The undulating, light-transmitting field serves as a primary visual focus within the house, and it references contextual influences such as ocean waves and site topography. As with any new venture, the hybrid composition of Liminal Mass presented a problem. “We had designed everything to fit together with the same tolerance, yet outside the digital realm, we had some error,” Smith says. The designers had to manually drill out several of the holes in the 3D-printed blocks to slot into the aluminum structure. Like most digitally fabricated work, final manual touches remain a requirement. “It’s always interesting for us to go from the digital to physical," she says. "It usually comes down to someone swinging a hammer to finish the installation.”
In Emerging Objects’ case, Rael and San Fratello were motivated to develop novel substances after facing hurdles in the use of standard materials. “Six years ago, we wanted to use 3D printers to print durable, architectural components, but it was too expensive and the materials were very much a 'non-material' used solely for prototyping,” Rael says. “Thus, we decided to make our own materials for 3D printing.” This new direction led to the development of unexpected qualities in seemingly known materials—or, as Rael describes, “ ‘natural’ materials that have ‘unnatural’ properties,” such as translucency, ultrahigh strength, or unanticipated surface textures. In a 3D-printed bench called the Seat Slug, the designers discovered that they were able to achieve surprising strength by integrating a polymer into the process, and developed a new translucent cement composite as a result. The creation of new materials presents its own set of challenges, however, particularly in terms of premature weathering. “We do not work in a temperature-controlled environment, so our work is often affected by the weather with sometimes interesting but sometimes disastrous results,” Rael says.
Both firms are optimistic about the increased use of additive manufacturing for practical applications in architecture despite its slow start. “It’s already making inroads into design in general,” Smith says. “Architecture proper is just a bit of a conservative industry and resists change.” She references Somerville, Mass.–based Nervous System’s dress and jewelry collections, as well as the pieces created by 3D Systems for Google’s Project Ara, as examples of component mass customization that represent a promising avenue for architecture.
For Rael, a remaining hurdle is the lack of virtual tools with sufficient knowledge of material properties—a challenge that will “require software manufacturers, or designers skilled in computation, to integrate material logics (strength, weight, translucency, and other material characteristics) with geometry for non-standard or homogeneous materials,” he says.
Smith points to related fields, such as building science and engineering, which are actively advancing a data-driven analysis of materials. “Part of the problem [for why] this is not as widespread in architecture is the cost of doing this sort of deep analysis,” she says. “However, with the increasing availability and thus affordability of digital fabrication machines, it’s becoming easier to not only propose structures with this level of complexity, but to realize them as well.”
Smith and Rael offer keen observations about disciplinary obstacles and opportunities in 3D printing. However, their firms' more important contribution is the demonstration of promising approaches for future design and construction. From Smith|Allen’s explorations in material hybridization and scaling to Emerging Objects’ experimentation with new materials, 3D printing may be viewed as a convincing—if still imperfect—method for realizing architecture.