“Is it plastic”? This is one of the most common questions 3D printing engineering company SQ4D gets when it comes to 3D printed homes. With the promise of cutting waste, reducing time on site and addressing housing shortages globally, some see 3D printing as the answer to many of the world’s problems. 3D printed homes are here and we share what we know about this sustainable way of building for the future.  

On the African continent, the city of Ben Guerir in Morocco was the first to house a 3D printed home. Be More 3D is a Spanish manufacturer that printed the 32 square metre house in just 12 hours. In Nates, France, the Ramdani family became the first in the world to move into a four-bedroom 3D printed house in 2019.  

3D-printed houses are created by using large 3D printers that can extrude concrete, plastic, or other building materials through nozzles to gradually build up a 3D object the size of a house. Only the frame and walls of the house are built; other elements, such as windows, electricity, or plumbing, need to be installed separately.  

Concrete is the preferred choice of building material for 3D printed homes, as it does not add any risks in terms of flammability or risks associated with poor construction materials.  There is no difference in the walls built by a 3D printer and the walls built by a construction team. A construction team, however can still get the measurements wrong – a robot cannot.   

3D printer reviewer Ludivine Cherdo explains the process in more detail, “House 3D printers use extrusion technology. Paste-type components such as concrete are used as filament. The material is pushed out of a special nozzle to form layers. To put it (very) simply, paste extrusion is similar using a piping bag to spread frosting on a cake”.  

The printer creates the foundations and walls of the building. The ground is the printer’s build plate. Some concrete 3D printers, however, are used to 3D print brick moulds. When moulded, the bricks are then piled atop each other manually (or with a robotic arm).  

3D Printing in South Africa  

South Africa has embraced 3D printing technology on many levels. From the medical field (the University of Pretoria has pioneered the world’s first middle ear transplant using 3D printed middle ear bones) to the possibility of sustainable housing – South Africa’s economic landscape makes 3D printed homes an obvious choice for low-cost and sustainable housing.   

A project that would usually take weeks can now be done in a matter of hours and for a fraction of the price and impact on the environment. From a sustainability perspective, homes created with 3D printing reduces a building project’s carbon footprint by 70 per cent.   

Medium-sized homes can be printed for as little as R150,000 making owning a house much more attainable to young people who not only want to own a home but also need to take care of their families.   

The lack of proper housing in South Africa is one of our country’s largest problems. The city of Cape Town alone has a housing backlog of more than 300 000 people registered on a waiting list for government-funded houses. The time, money and infrastructure it takes to build these homes traditionally is not a viable option for the poor anymore. 3D printed homes can solve this problem for us.   

There are not any community 3D housing projects on the go yet in South Africa, and the idea of 3D printed homes is something we may only enjoy in the near future. 3D printed homes is a new concept all over the world. One can imagine that there is a specific skillset involved to successfully complete such a project, but is it the answer to low-cost housing? Yes. 

Machines  

Numerous companies have created 3D printers for construction. The skillset and technology that goes into engineering one of these robots are of the highest standard. COBOD BOD2 is one of those machines. Whether you are constructing a home in Europe or a school in Africa, as they are doing in Malawi, it comes down to this machine. At Construction of Building on Demand (COBOD), they strive towards full automation in the construction industry by designing robotic 3D construction printers and automated processes for the building site. Watch COBOD in action.  

Another 3D printer at the forefront of technology is the Vulcan II printer from ICON. ICON wishes to revolutionise the construction field. The whole process is designed to be user-friendly with a tablet-based interface, and ICON’s Lavacrete concrete mix is optimised for easier printing.  

Batiprint 3D made international headlines when completing their Yhnova 3D printed house in Nantes, France, mentioned above. Their 3D printer not only prints cement but also insulation foam, which makes it one of the most complete 3D construction solutions.  

The Possibilities  

In SCULPTEO‘s 2021 Ultimate Guide to 3D printing for Construction and Architecture Projects paper, they write “3D Printing in the construction industry means greatly reduced production time. That’s because the machines themselves are very fast, some of them are capable of manufacturing a 600 to 800-square-foot (55 to 75-square-meter) home in just 24 hours”.   

Using 3D printing in construction saves production costs on material waste. SCULPTEA continues, “That’s because a 3D printer with robotic arms uses exactly the amount of material it needs. Producing buildings layer by layer and with lattice structures inside allows for a huge cost reduction. Not only that, but they are also capable of using recycled materials. This factor also benefits the environment”.  

The Limitations  

We were lucky enough to get a word in with Gerard Vermaerke, Marketing Director at Envioneers. Gerard says as wonderful as 3D printing is, there are a few things to take into consideration. The material that’s being printed, the scale (size) of the part (house) being printed (constructed), and time and design are all delicate factors to take into consideration.  

“Material is normally (although there is a huge variety available) a thermal plastic that sticks to itself and sets fast as it prints. The challenge with 3D printed homes is to get a cement-like material that can behave similarly. Scale is also a challenge. Most bed size’s (printable area or volume) is 250 mm X 250mm X 200mm. Which is the size of a large brick. To get a printer head that moves 10 meters or more in three different directions is going to have to be a very big three-axis machine. Lastly, the Design. 3D printers require what we call “scaffolding” to be printed that support the negative spaces under overhangs. For example, to 3D print a ceiling you need to print the entire room full of scaffolding – just for a ceiling. The design of the structure is key to its feasibility as a 3D printed product“. 

Due to the specific skillsets required to make 3D printed homes a success in South Africa, it may take a while before we too can enjoy the benefits of this innovative technology. Watch this space.