3D printing promises to transform architecture forever – and create forms that blow today’s buildings out of the water

James Rose University of Tennessee – In architecture, new materials rarely emerge.

Concrete, masonry, and wood have been the mainstays of many structures throughout history.

The steel frame revolutionized architecture in the 1880s. Steel enabled architects to design taller buildings and larger windows. This led to the creation of skyscrapers today.

Construction materials have been restricted to a limited number of mass-produced parts since the industrial revolution. This standardized set of parts, which includes steel beams and plywood panels has been used to design and construct buildings for more than 150 years.

That may soon change with advances in what’s called “large-scale additive manufacturing.” Not since the adoption of the steel frame has there been a development with as much potential to transform the way buildings are conceived and constructed.

A large-scale additive manufacturing process, such as desktop 3D printers, involves the construction of objects one layer at time. Whether it’s clay, concrete or plastic, the print material is extruded in a fluid state and hardens into its final form.

As director of the Institute for Smart Structures at the University of Tennessee, I’ve been fortunate to work on a series of projects that deploy this new technology.

Although there are still some obstacles to widespread adoption of this technology, I see a future where buildings will be built entirely out of recycled materials or materials sourced on site, using forms inspired by nature’s geometries.

Promising prototypes

One of them is the Trillium Pavilion. This open-air structure was printed using recycled ABS polymer. A common plastic used in many consumer products.

The structure’s thin, double-curved surfaces were inspired by the petals of its namesake flower. The students designed and printed the project at Loci Robotics. It was then constructed at Cherokee Farm, University of Tennessee Research Park in Knoxville.

Tecla is another example of large-scale additive manufacture. It is a prototype dwelling that measures 450 feet (41.8 meters) and was designed by Mario Cucinella architects. It was printed in Massa Lombarda in Italy.

Tecla was printed by the architects using clay from a nearby river. This unique combination of cheap material and radial geometry resulted in an energy-efficient alternative housing.

Back in the U.S., the architecture firm Lake Flato partnered with the construction technology firm ICON to print concrete exterior walls for a home dubbed “House Zero” in Austin, Texas.

The home, measuring 2,000 feet in area (185.8 square meters), demonstrates the efficiency and speed of 3D-printed cement. It also features a striking contrast between the curvilinear walls and the exposed timber frame.

Planning

Three knowledge areas are required for large-scale additive manufacturing: digital design, digital fabrication, and material science.

To start, architects create computer models for all components that will be printed. This software allows the designers to analyze how the components will perform under structural forces and adjust the components accordingly. These tools can be used to help designers reduce weight and automate design processes such as smoothing complicated geometric intersections before printing.

Slicer software is a piece of software that converts the computer model to a set instructions for the printer.

You might assume 3D printers work at a relatively small scale – think cellphone cases and toothbrush holders.

3D printing technology has allowed hardware to scale up significantly. Sometimes the printing is done via what’s called a gantry-based system – a rectangular framework of sliding rails similar to a desktop 3D printer. Because they can print in any orientation, robotic arms are increasingly being used.

The printing location can vary. While smaller parts and furnishings can be printed in factories for printing, entire houses must be printed on site.

Large-scale additive manufacturing can be done with a variety of materials. Concrete is a popular choice because of its durability and familiarity. Clay is an intriguing alternative because it can be harvested on-site – which is what the designers of Tecla did.

Polymers and plastics could be the most versatile. These materials have a lot of versatility and can be tailored to suit a wide variety of aesthetic and structural requirements. These materials can also be made from organically and recycled materials.

Inspiration from nature

Because additive manufacturing builds layer by layer, using only the material and energy required to make a particular component, it’s a far more efficient building process than “subtractive methods,” which involve cutting away excess material – think milling a wood beam out of a tree.

Even common materials like concrete and plastics benefit from being 3D-printed, since there’s no need for additional formwork or molds.

Today’s construction materials are mass-produced using assembly lines that are specifically designed to produce identical components. This process reduces cost but leaves little room to customize.

Large-scale additive manufacturing eliminates the need for tools, forms, or dies. This allows each part to be uniquely created without any time penalties for additional complexity or customization.

Large-scale additive manufacturing also offers the possibility to create complex components with internal gaps. This could allow walls to be printed with conduit and ductwork already in position.

In addition, research is taking place to explore the possibilities of multi-material 3D printing, a technique that could allow windows, insulation, structural reinforcement – even wiring – to be fully integrated into a single printed component.

I find it fascinating that additive manufacturing, which is a process of building layers with a slow hardening material, mimics natural processes like shell formation.

This creates opportunities for designers to design geometries that are hard to achieve using other construction methods but common in nature.

A lightweight lattice of tubes could be made using structural frames inspired by bird bone’s fine structure. Façades that evoke the shapes of plant leaves might be designed to simultaneously shade the building and produce solar power.

Learn from your mistakes

Despite all the positive aspects of large scale additive manufacturing, there are still many barriers to wider adoption.

The biggest challenge is its novelty. The entire infrastructure is built around traditional construction methods like concrete, steel and wood. This includes supply chains and building codes. Additionally, digital fabrication hardware costs are high and there is limited instruction in the skills necessary to design with these new materials.

3D printing in architecture will only be successful if it finds its niche. Like word processing, I believe it will be large-scale additive manufacturing which will make it more popular.

Maybe it will be its ability print extremely efficient structural frames. I also already see its promise for creating unique sculptural façades that can be recycled and reprinted at the end of their useful life.

Whatever the case, it is likely that future buildings will be 3D printed in some form.

James Rose, Director, Institute for Smart Structures University of Tennessee

This article was republished by The Conversation under Creative Commons. You can read the original article.