Table of Contents
For the past few years, there has been almost daily news coverage of 3D printed homes and construction. But what are these homes made of?
A general list of materials successfully used in projects like WASP’s Gaia, the Fibonacci House, the Canal House in Amsterdam, and other 3D printed housing projects is available, even though the precise combinations or amounts may not be known to the general public. This shows how established, and emerging technologies interact and provides a preview of potential future developments.
This article will look at the materials used in 3D printing construction, whether for prototypes, unfinished projects, or operational structures.
Materials of 3D Printed House: Concrete
Confusion may result when considering concrete because the two words occasionally interchangeably. Additional ingredients include cement, water, sand, gravel, or crushed stone.
Most 3D-printed housing projects you’ve heard of used materials that resembled concrete but weren’t necessarily made of concrete. As previously stated, this indicates that a combination of cement, sand (or crushed stone or gravel), fibers, and sporadically other materials are used.
Portland cement, which is not a specific brand but a generic type of cement that is most frequently used, is the main component of most concrete mixtures. As reported in IIT Tech Ambit in 2021, projects like the first 3D-printed house in India from Tvasta based their concrete mix on Portland cement.
Other businesses have chosen to develop and use their own proprietary concrete materials due to the difficulties that concrete (or a more conventional concrete-based mix) presents.
Materials of 3D Printed House: Proprietary Concrete
As previously stated, cement (typically Portland cement), sand, and other materials are combined to create concrete. How about proprietary concrete, though? It’s critical to recognize the difference because many businesses engaged in 3D printing homes (or researching the technology) have created their own exclusive concrete mixtures and are integrating them with closed-use compatibility into their machinery. Proprietary concretes are made to avoid these problems because conventional concrete isn’t suitable for 3D printing. After all, it would clog the printer nozzle and not adhere properly to the previous layers.
These businesses use one or more specialized additives in place of Portland cement that isn’t always specified but are necessary to make the mixes work. The advantages of these 3D printed house concrete make it much simpler to 3D print concrete using the standard extruder model, whether using a gantry or stand-alone machine. Although the durability of the homes has not yet been proven over the long term.
A Few Examples
Using “concrete, gypsum, and proprietary materials developed by the company,” according to Apis Cor, the first two-story project in Dubai (the largest at the time of completion) was 3D printed. They don’t provide any more information on the ingredients or offer any of the materials for sale for use outside of their own printer.
According to the company, the House Zero project in Austin by Icon, which received a lot of media coverage during South by Southwest (SXSW), was built with a “proprietary cementitious-based material, ‘Lavacrete,’ insulation, and steel for reinforcing.” The rest of their ambitious projects in Texas will be built on this proprietary material.
One of the first businesses, Winsun, printed buildings in its Chinese facility using 3D printing technology before shipping them overseas to places like Dubai. These structures were built using their unique Special Reinforced Concrete, which they will also use for future projects.
When SQ4D unveiled the first commercially available 3D printed home for sale, they directly contrasted “SQ4D concrete” with “standard concrete” to illustrate the benefits without disclosing what makes their concrete unique or the components used in the mixture.
DFab, a different proprietary concrete mixture, merits special mention. Contrary to the previously mentioned closed-use concrete, a joint venture between COBOD and Cemex produced this as a widely compatible concrete mix specially designed for 3D printing construction. They are currently using it to print homes in Oman using COBOD’s BOD2 printer, but their ultimate goal is to have it work with all types of cement printers.
Builders can find 99 percent of the ingredients for this unique mix locally. Still, the final additive ingredient—Magic COBOD’s Mix—is required for the DFab mix to function correctly.
Since bricks (and the highly skilled tradespeople who apply them) do not have a place in 3D printed construction. Mortar is getting its chance to shine in the world of home construction. Mortar is best known as the material that lies between layers of bricks, but it is now taking its place in the spotlight.
Mortar is traditionally made from a mixture similar to that of concrete, with the addition of lime as a key ingredient. Because Mortar is less durable than concrete, it is used as a binder between layers. On the other hand, Proprietary mortars are more malleable with 3D printers than conventional concrete, which is advantageous for the extrusion process and results in fewer nozzle clogs or mistakes between layers.
The Fibonacci House, one of the most well-known 3D printed homes, used Mortar to build its walls, but it’s not the only one. Mortar is used mainly in other recently finished housing projects from Peri and 3D Printed Farms. Most of the Mortar is produced by businesses like Laticrete that create it specifically for 3D printers and their extruders.
Could you provide us with a list of 3D printing materials that omits plastic? One of the first houses to be 3D printed was made of plastic, so the makers taking on the housing challenge don’t believe that is the case. We’re referring to the Amsterdam 3D Printed Urban Cabin, created in 2015.
This project was proud to use bioplastics and recycled shredded water bottles to be environmentally friendly, even though some might object to plastic use compared to other more robust or sustainable materials. Additionally, they stated that the entire house will be recycled after it is no longer used. We can’t recall the last time we overheard a traditional home builder boast that every single component was recyclable.
Local Natural 3D Printed House Material
Only a few materials can be considered environmentally friendly substitutes for their source and transportation.
Sometimes, for new technologies to succeed, inspiration must come from a long-gone era. Humans have constructed their homes out of Mud and other organic earth materials for thousands of years. Since Mud doesn’t need to be transported to the construction site, building mud houses is one of the most environmentally friendly construction methods.
In northern Italy in 2020, the 3D printing company WASP produced homes successfully using only Mud. The project collaborated with Mario Cucinella, an Italian architect. And unsurprisingly, it caused a lot of buzzes. Although WASP’s printer is sophisticated, it can be transported worldwide and successfully operated by printing on the local surface.
The WASP initiative’s aim of combating climate change and reducing emissions will have plenty of opportunities in rural and developing communities. However, we might not see these houses in Manhattan or London.
Rice waste made up 65 percent of the materials used to print the Gaia house, making it yet another material deemed successful thanks to the efforts of the Italian 3D printing company WASP. The remaining 25% was made up of regional soil (such as the Mud mentioned above). The remaining 5% was made up of rice waste, which consisted of rice husks and straws that would have otherwise been disposed of.
The same combination of unprocessed fibers (rice waste), clay, soil, and sand was used to replicate this procedure more recently for a collaboration with Dior to print two pop-up stores in Dubai.
Many 3D printing businesses promote sustainability and the advantages of technology. Still, WASP is one of the organizations leading the way with concrete outcomes. WASP was able to transform waste into a livable structure and produce a home with no harmful environmental effects.
Although cement is a common building material, some of its constituents are becoming more well-known. Sand is the first of these materials.
In 2010, D-Shape was one of the first well-known cases of using sand in building a house. To do this, they extruded a layer of sand at high temperatures and speeds, followed by a material that hardened and solidified the sand before adding the next layer.
Because the 3D printing process is similar to that of a hobbyist machine at home. There is no concern about the construction being blown or washed away. But with an additional step to bind the sand.
Sand is already used for 3D printing industrial molds. It will probably expand in the future, even though construction printers aren’t yet ready to handle it.
In the past few years, metal 3D printing has advanced incredibly. Businesses like MX3D want to apply this technology to the building and architectural industries. Metal bridges and essential elements of commercial buildings can already be successfully produced using 3D printed metal. Metal hasn’t yet been used in a finished residential project, but it will happen eventually.
Steel seems to be their preferred metal, but 3D printing now offers a vast selection of metals, and they’re willing to try any that might work. There isn’t much evidence to suggest that this won’t happen soon.
Other 3D Printed House Materials
This list has a wide range of materials. Still, it only scratches the surface of what the construction industry will encounter in the future.
Intending to make them strong and dependable enough for home construction, Black Buffalo has already unveiled a line of experimental dry mixes that can be used to print various new materials. Black Buffalo claims they have “undergone extensive in-house, partner level, and external testing to exceed traditional requirements for a building.” We have yet to see their advantages and disadvantages in practice. Clay, wood, hemp, oyster shells (which are already a typical building material as the main component of tabby concrete), colored clays, and clay are some of these materials. Construction could undergo a revolution, with the materials mentioned in the article only marking the beginning.
Although crushed stone can be a component of some of the concretes mentioned above, it is a much more expensive and long-lasting material renowned for its smooth surface when used alone. Some ambitious housing projects from businesses like Mighty Buildings and Concr3de have used stone or stone-like materials.
It’s important to note that, similar to concrete, the stone is undergoing the development of various proprietary versions to make 3D printing with it much more straightforward. Winsun’s “Crazy Magic Stone,” which they refer to as “an artificial stone,” and the substance “Light Stone,” which Mighty Buildings use for its pre-constructed walls and “cures into a stone-like composite,” are two examples.
It’s crucial to stay up to date on what businesses are working on and to envision what the future may hold, given the advancement of technologies and the requirement to build more sustainable and accessible housing.
Many businesses are experimenting and testing ways to build habitats on the Moon and possibly other planets using local soil due to recent advancements in space exploration.
Icon has been given permission to work on a new project that will increase the ability to build on various planets. If the project is a success, Icon might be allowed to test on the lunar surface, advancing the development of 3D printing and construction technologies even further.
LINA, a 3D-printed structure revealed by AI SpaceFactory and the NASA Kennedy Space Center, is also located in the same region. It is intended to serve as a lunar outpost for astronauts. The construction would be 3D printed using lunar regolith and an Earth-sourced polymer, shielding it from lunar-specific hazards like radiation, thermal oscillations, and seismic activity. However, unlike conventional 3D printing, LINA will be printed at a 60° angle instead of parallel to the ground because of the design’s vaulted roof (or the build plate).
While technology is constantly changing to support the use of various materials on Earth (and beyond), it is evident that restrictions are eroding to make way for more options.