buildings

The potential of additive manufacturing, also known as 3D printing, to change the way buildings are made is indisputable. It’s being touted as a solution to challenges in our cities ranging from the need for affordable housing to infrastructure modernisation. The process has been slow, but it may well be a key ingredient in the future of the building industries.

In the last two years, technological advances in scalability are allowing 3D printing to move beyond small-scale architectural models and prototypes. It is now being used in actual housing and infrastructure construction—achieving lower labor costs and finally delivering those long-promised economies of scale.

Helped along by the increasing prevalence of digital 3D modelling software for building and infrastructure design, some of the new results are pretty mind-boggling, too.

Here are three of the latest examples from around the world, which reveal the ways in which 3D printing is changing approaches to architecture, engineering and construction.

1. Kurilpa Bridge, Brisbane

Road and bridge infrastructure is just as important as housing to make cities liveable and workable. Until recently, direct metal laser sintering (DMLS), essentially 3D printing metal parts, was used extensively in the aerospace and automotive industries. But it was not explored thoroughly for usability and cost-effectiveness for bridges and other types of urban infrastructure. The primary reason is because each bridge is a unique design and the savings from prototyping and manufacturing aren’t as obvious.

Moving now to Australia, global engineering firm Arup was tasked with creating components for an unconventional pedestrian bridge. Arup decided to use 3D printing as an internal research project to determine how a laser-sintered, printed metal part could hold up to structural standards. The parts for such a bridge also had to be load-bearing connections.

Arup’s engineers came up with a complex design with “root” supports and extra struts were added to the part to support it during printing. The struts allowed for a hollow design that reduced the overall weight of the bridge node and was more aesthetically pleasing than a traditionally machined one. The design and production of the bridge nodes allowed new degrees of design freedom and Arup is already using the research on other projects.

2. Canal House, Amsterdam

The first entrant in the race to build a fully 3D-printed house is Amsterdam’s DUS Architects. Using The KamerMaker (room builder), a 20-foot-tall custom 3D printer created by DUS and Ultimaker, the architecture firm has been printing a house along one of Amsterdam’s famous canals bit by bit for the last year-and-a-half and expects to have it completed in 2015.

The KamerMaker works essentially like a larger version of a desktop Makerbot. The printer head extrudes the melted plastic material along the programmed path on the X and Y axes and when finished moves up one step along the Z axis. Unlike its desktop cousin, it can print whole rooms.

The exterior walls of the Canal House cover a range of sustainable materials, including Hotmelt—a type of industrial glue developed by German chemicals manufacturer Henkel. Comprised of 80 per cent vegetable oil, Hotmelt is used to form bio-based plastics. DUS and Henkel are also experimenting with eco-concrete. They are testing out a variable concrete mix that allows the team to add insulative material and colour to the wall sections. Once printed, the wall sections fit together sort of like Lego.

While the Canal House won’t be completed until next year, it has already created several innovations, including one of the largest-scale 3D printers in the world and advances in sustainable materials.

3. WinSun Houses, Shanghai

On the other side of world comes an entirely different perspective on 3D-printed housing. While the Canal House is experimental, architecturally elegant and pushes the envelope of materials science and constructibility, it will take three years to complete.

Meanwhile, Shanghai WinSun Decoration Design Engineering claims to have erected 10 3D-printed houses—each costing about $4,800—in less than 24 hours.

There’s some debate over whether Shanghai WinSun’s houses are genuinely a 3D creation because they were printed not as a single item, but in parts that were then assembled onsite. But the feat is impressive nonetheless.

The simple, concrete-framed buildings were made using an enormous 3D printer that is 150 meters long, 10 meters wide and 6.6 meters high. The houses each cover an area of 200 square meters and were designed to someday provide affordable housing to the homeless.

The 3D-printed “ink” of each structure is a combination of recycled construction and industrial waste materials formed into structural concrete and wall panels.

These houses may not win any design awards, but the manufacturing concept that delivered them so cheaply and quickly is a leap forward in sustainable tilt-up construction. The process contains costs and could be applied to solving housing crises in major cities around the world.

New Uses For 3D Printing

The above examples are just three among the many new uses of 3D printing at building scale that are popping up around the world. They clearly point to a world where advances in 3D-modelling software in combination with advances 3D-printing technologies (both in terms of size and materials like concrete and carbon fibre) will allow architecture and construction professionals to more efficiently and more sustainably design and implement building solutions for our rapidly urbanising planet.

As the organic form of Arup’s root supports suggest, 3D printing may also indicate a future of beautiful new architecture and infrastructure in our cities.