3D printing of buildings and assisting construction

  • 3D printing could become ‘critical’ in providing affordable homes with some estimates as low as $4,000
  • Government house building targets to reach double current rate by 2022 – providing opportunities for execution
  • Construction market ripe for 3D printing by new and disruptive entrants

Three-dimensional printing, also termed Additive Manufacturing, refers to the layered production of materials to create an object or shape which has three-dimensions – length, width and height.

It’s possible to 3D print a wide range of items – from manufacturing equipment and medical appliances to edible cake decorations and shoes. One of the most documented medical uses of a 3D printer, is to produce prosthetics at a massively reduced cost. Elsewhere, when applying the process to the construction industry adhesive material such as concrete or molten steel is deposited in layers to print buildings via a giant robotic nozzle. The media coverage includes reports of arty and ultra-modern looking dwellings – such as the five bulbous homes built in the Dutch city of Eindhoven.  In January 2019, the world saw the longest printed concrete bridge installed in Shanghai, China, while Denmark-based COBOD and PERI recently 3D printed the walls of four houses in four days at the bautec 2020 exhibition. Such clever applications have provided excitement about the possibilities for the building industry and householders alike.

Advantages and disadvantages within construction

The three-dimensional printing technique was first developed in the 1980s, but had limited practical applications. It was expensive and challenging to deploy. It’s come a long way since the 80s, but suitable 3D printing techniques and materials are still being researched. However, applications by early adopters in the construction trade are already demonstrating how it may benefit and complement existing modern methods of construction (MMC) – such as prefabrication and the use of modular components.  Although the topic is still evolving, 3D printing has the potential of simplifying key processes in the building lifecycle, such as the design for manufacturing principles. It also stands to reduce waste while increasing the quality of the final output – at a fraction of the cost. Specifically, using robotics may allow for more accurate construction, while mitigating the need for complex work to be carried out by humans on-site.

Another advantage of 3D printing is its sustainability, as much less concrete is required and hence less cement – reducing the CO2 emissions created by the production of the cement.

Nevertheless, there are several challenges with 3D printing, including the scale of project that can be delivered. Currently the size of the models produced makes it difficult to print a whole 3D model at once. Furthermore, three-dimensional printing materials can be problematic – as often contractors have little knowledge of them and the assembly techniques required. This has the potential to result in poorer quality finished structures and the possibility of additional risks. Stringent practices should be in place to ensure the fire safety measures are robust and rigorous, as well as deepening the understanding of how such constructions behave in the event of flood or escape of water.

A country in need of quality social housing

Research last year showed that the country was on course for its worst decade for housebuilding since the Second World War. The UK’s housing infrastructure delivery has been under pressure for a number of years and the government needs a solution to achieve its targets at nearly double current rates. In order to meet this quota, the industry needs to look at new and innovative methods of construction. As traditional masonry construction is unable to meet the demand, there is an urgent requirement for the housebuilding sector to devise new processes. Building techniques such as 3D printing may become critical in assisting delivery of the volume of housing required, whilst meeting important regulatory standards on safety.

One can see how innovators are disrupting the market and using 3D printing to help those most in need of new homes in El Salvador – where homelessness is a big problem in the densely populated country. An organisation called ICON, in partnership with charity organisation New Story, plans to build a neighbourhood of economical 3D printed houses. The prototype for the three dimensional printed home cost around $10,000, but ICON claims that it can be lowered to just $4000. The build time for ICON’s 3D printed house is approximately 24 hours. There are also possibilities here for quickly delivering emergency shelters in times of crisis, for example, following a natural disaster.

There are many clear benefits of three dimensional printing including the cost and time saving. And although 3D printing is not a sole solution to all of the problems in the construction trade, there is a huge prospect for disruption. New and emerging enterprises are driving innovation and change – and with this comes the opportunity to help the UK to tackle the problem of under-supply of affordable housing. We mustn’t forget, however, that with all innovative practices we alter the risk landscape and the new risks we introduce should be researched, understood and mitigated from the design phase, through implementation and inhabitation of these buildings.