The construction industry has long been fascinated by and a target of 3D printing. However, until recently 3D printed houses were highly experimental, few and far between. In the last few months additive manufacturing (AM) has made some huge strides in the construction business as small 3D printed homes were offered to the homeless and a 3 bedroom 2 bathroom home to be 3D printed was offered for sale last week. Let’s take a look at these and other recent developments in the use of 3D printing for construction – some uses are more conventional than one might think.
Hot Off the Construction Site
The latest news in this department is the 1500 sqft (~140 sqm) 3 bedroom, 2 bathroom house offered for sale in Riverhead, NY for just under $300k. The house includes a detached 750 sqft ( 70sqm) 2.5 car garage (also 3D printed). The technology and construction company in charge is SQ4D, a company that already has some achievements in this space: in early 2020 they completed a 1900 sqft (~175 sqm) single story house in Calverton NY. The company claims this was the largest 3D printed house at the time. The entire house was 3D printed in under 48 hours over 8 calendar days by 3 people and used under $6000 of materials. This is a fraction of the cost of materials and build time used for a conventionally built house. The company expects its ARCS (Autonomous Robotic Construction Systems) technology to further improve and require half the time this house did. So, if you want to see on the inside of this Calverton house (pictured below), here’s a video from CNBC where they claim the upcoming Riverhead NY house is priced at about half the local cost of new construction. Of course, 3D printing the walls is not enough – the house needs electrical, plumbing, fixtures etc and those are added as in any house. SQ4D also does not print the roof so traditional roofing is needed. As many home builders know, in calendar time it’s the finishes that take up the most construction time and there AM is of no help at the moment.
From the Homeless to the Moon
Construction technology company Icon took a different approach than SQ4D. While the latter concentrates on family homes with a sizeable footprint, Icon concentrated on small houses for those that don’t even have that – the homeless. Icon has built housing project with houses in the 400-600 sqft (37-55 sqm) range that offer the homeless a small home in specialized communities that support them. One of their projects was in Mexico and another, called Community First, is in Austin TX. Community First offers a variety of affordable housing which includes mobile homes as well as 3D printed small homes (picture up top). The affordable cost and quick timeline of these 3D printed houses make them attractive as solutions for homelessness around the world. Icon translated the experience it gained in these projects to its proposal to 3D print houses on the moon – and won a NASA contract!
Layer by Layer, Brick by Brick
Both examples above have the deposition layered texture in common. One way to reduce this effect is to add a flap to the side of the nozzle that follows it and smooths the just deposited layer. COBOD (Construction Of Buildings On Demand) offers this as part of their Tangential Nozzle Control. But what if you want a brick wall? Can a 3D printer help? In its basic definition, a 3D printer deposits material layer by layer, whether it’s melted material, paste, or drops. I would argue laying bricks automatically layer by layer can be called 3D printing as well. This is exactly what the Hadrian X brick layer does. It was developed by Fastbrick Robotics (FBR) using its stabilization technology to ensure smooth and precise brick laying layer after layer. As with any digital manufacturing or construction project, software plays a key role in determining the bricks to be laid and offsetting changes in the environment to ensure stability. In the big picture (see above) it looks very similar to what we see with a concrete extruding 3D printer at work only in this case the deposition is in discrete units of bricks rather than a continuous paste. The result is a house that is made of bricks and has a similar feel to a hand built one – the display house they created fits in the community like the other houses and in fact a week or 2 ago they handed the keys over to its first inhabitants.
The promise of 3D printed houses is a faster and more affordable construction process. Both speed and cost savings are achieved by automating the building process to speed it up and require far less manual labor and enable more efficient use of (less) material. In expensive areas, where labor costs can be very high this technology has even more potential – hence the recent round of Bay Area based Mighty Buildings which plans to replicate its factory elsewhere. Other players, including those mentioned above, plan to sell their 3D printers and potentially specialty materials to construction companies – the initial homes serve as a sort of proof of concept. The one hurdle in this plan is the transfer of knowledge of how to handle the materials and the machine settings in different climates, terrains, etc. When they get to this stage, LEO Lane can help. Until then, like everyone, we will enjoy watching the videos of these houses being 3D printed.