3rd Jun, 2020
In 1983 Charles Hull developed the first successful 3D printer. Over the years this technology has evolved to be used for more than just the printing of objects, it has become a frenzy in many different industries. We will be focussing specifically on how 3D printing has been incorporated in the construction industry.
3D construction printing consists of the 3D printer that is controlled by a computer and prints layer over layer with concrete (or a mixture of additives suitable to qualify as construction material). It has many advantages from an overall perspective, especially when considering cost and time, which are the greatest factors that are considered when initiating a new project. It also reduces waste and labour during construction.
Let us say we compare a project that will take weeks, or even months to complete, should it be constructed the conventional way; it may be possible to construct the same within hours or days. Sure, it would not look the same since it is not constructed with “conventional” building materials, but it will serve the same purpose. This just shows how it influences the time frames required for construction, it opens a world where we can do much more in less time and at less cost. This also influences the contractors in a positive way, as they can complete more buildings than they previously could. A project that will take roughly 6 months, can be completed in less than 2 months.
When comparing cost specifically, it is much cheaper due to material costs, almost no wastage (according to Neil Strother’s post on Forbes, 3D printing only has 30% of the waste that conventional methods of construction have), less time allows for better management of resources. The biggest trials that construction industry will face is letting go of some of the staff, as you will only need personnel to manage and oversee, as well us placement of items like placement of rebar, windows, door frames and doors, roofing, depending on the requirements of finishes, plaster and paint, tiling, ceilings, etc. but the structure itself (being concrete / precast brickwork) will be done by the 3D printer.
The question comes in when asking how durable this method of construction is and how does it compare to the requirements regarding concrete strength, finish etc. Well, testing of concrete strength is still a requirement for 3D printed buildings, but this method is believed to be better than and last longer than conventional buildings.
The biggest limits we face in terms of development will be the fact that it is something new, the number of architects, engineers, etc that have designed 3D homes and constructed them, are extremely limited. Our building codes and regulations do not make provision for 3D printing specifically, even though some trades are still required to be conventional, this is something that will need to be formalised. In South Africa specifically, there has been numerous requests to start looking into the methods of 3D printing for affordable housing, however the only real sign of initiation of 3D printing is the fact that a research programme has been launched at the Stellenbosch University’s Centre for Development of Sustainable Infrastructure (CDSI), where a 3D concrete printer was designed and manufactured for research purposes. It seems that the challenge lies with the theoretical connection to the practical application thereof.
Is this our future?
Keeping all the above in mind, it is undoubtably a way of saving time and costs, but my concern lies with the limits that this method has on design. I think it is the perfect method to introduce to low cost housing and especially for developments where duplication of units take place. When looking at developments, including residential, commercial, retail, etc. of today and how construction has become a form of art rather than just a building, how we have evolved with technology and especially different materials that are used to create a “personalised art piece”, I think it would be hard for people to accept the limits. But on the other hand, there are numerous developments that prove that the limits are not that big of a deal as it allows a different and new form of creativity.
Fact or fiction? The concept of 3D printed developments might seem futuristic, but it has been gaining traction in the construction industry over the past few years. Below are a few developments done by using 3D printing.
The common designs came across as being one- to two- storey buildings, but WinSun, a company in China, have developed a five- storey apartment building using the largest 3D house printer in the world, in 2015. According to WinSun they had cut construction time by 70%, cut cost of building materials by 60% and about an 80% cut on labour costs. They also claimed that management of the site was easier, and noise and dust levels were low throughout the construction period.
WinSun uses a mixture of cement, glass fibres and recycled construction waste as the mixture they print with, making it an eco-friendly development.
WinSun has also developed 10 houses of 200m² each within 24 hours. They did this by pre-printing sections of the houses at their warehouse, transporting the sections to site and erecting the house on site.
Here you can go look at this video posted by Apis Cor (one of the leading companies in 3D construction printing), where they have constructed the biggest building yet using a 3D printer. It gives a particularly good idea of where we are heading and how successful it already is.
ICON has developed the Vulcan II printer together with the robotics controlled with a tablet, software and materials capable of 3D printing. They claim to be able to print homes of up to 2,000m². ICON together with New Story have initiated a project where they have developed houses for a community in Tabasco, Mexico, 46.5m² houses with a living room, kitchen, 2 bedrooms and 1 bathroom constructed in only 24 hours.
Another form of 3D printing that we have not discussed, is 3D models. Since most developments today are designed using technology that allows us to see the development in 3D on our computers, as well as BIM being used more frequently, we might as well start using the information available to print 3D models of the developments prior to construction. This will allow the client to truly see his development as it will be once finished.
Honestly, this will have a great effect on our future as it develops.