A post office in India is a very common building that may seem common to you, but soon you may change your mind. Because currently, India is building a 3D-printed post office in Bangalore. It is expected to take only one month to complete and cost only 2.5 million rupees. If they had used traditional techniques to build it, the project would have cost four times as much as 3D printing.
This prompted the thought, “If 3D printing is so cost-effective, why don’t we just use it to solve the affordable housing problem?”
After all, by 2030, 40% of the world’s population will need affordable housing. We need to build 96,000 homes a day to house those people. That’s certainly a daunting task. Why not use 3D printers to speed up the process?
But the answer is a little more complicated than a simple “yes” or “no.”
Before we get to that, let’s look at how a 3D-printed house works.
First, 3D design software is used to prepare the desired architectural design. The data is then imported into a giant 3D printer – a 15-foot-tall machine. Then, a special concrete mixture is fed into the 3D printer. Usually, this mixture is much thicker than regular concrete. If you want to build a rectangular room – the machine can pipe the concrete in a rectangular motion, building a room row after row. If you want a curved room, that’s easy too.
This process saves time. And it doesn’t require as many workers, either.
In addition, 3D-printed buildings have another big advantage – sustainability.
The construction industry generates nearly 30% of the world’s waste. It includes packaging materials, excess cement, wood, bricks, and other materials left behind. With a 3D-printed house, builders only need to print exactly what they need. Waste can be minimized in this way.
In Malawi, for example, 3D printing reduced construction waste nearly 10 times and even reduced CO2 emissions by up to 70 percent.
So if it’s faster, cheaper, and greener, what’s stopping the world from embracing it to address the affordable housing crisis?
The first issue is scale. Although 3D printing has been around for decades, it hasn’t ignited a market; in the U.S., for example, there are around 10 companies engaged in 3D-printed buildings, and in India, there are still very few such companies. In addition, companies looking to enter the industry must make a massive one-time investment, and unless they get a large construction order for a 3D-printed home, it’s not a viable venture.
The second is the problem with 3D printing itself. While many companies have been able to use large 3D printers to build one-off structures, they have not been able to print functional buildings consistently. As one article points out – “Traditional buildings are not made by extrusion or casting or any other single manufacturing process; they incorporate dozens of different technologies, from poured concrete to spot-welded steel extrusions to laminated glass. How does one process replace the dozens of others we currently use?” The third issue is an incentive. The government rightly recognizes that 3D printing can be used for specific use cases. It might even be “affordable housing projects. But unless they can incentivize manufacturers to make large-scale investments, things won’t go exactly how you expect.
Affordable housing requires more than just cost-effective construction methods. It also requires low-cost land. And because the land is in short supply, the only way to get the job done is to start printing multi-story homes. However, 3D printers have not yet been deployed to build multi-story homes.
So there’s still a long way to go before we start 3D printing houses. We hope to find a solution for affordable housing.