Researchers 3D-Print a Concrete Roof

The Smart Slab, made with 3D sand printing, is only 20 millimeters thick at its thinnest point and less than half the weight of conventional concrete.

A few weeks ago, we learned about 3D-printed homes. They were small, low-cost ($4,000), and printed in 12 to 24 hours. Many Engineering By Design faithful wanted to know how they made the roof. It was a standard metal roof: anticlimactic.

Well, now it looks like the roof could soon be 3D printed as well.

Researchers from ETH Zurich have created the Smart Slab, an 80-square-meter concrete slab made with 3D sand printing. At its thinnest point, it's only 20 millimeters thick, and it is less than half the weight of a conventional concrete slab.

What's interesting is that the process makes it possible for designers to create intricate, and smart, designs in CAD software, which are then formed through a multi-step process. They are intricate (as you can see the organic shapes in the design), and smart in that they can design in the pathways for the electric cables.

The team prints the formwork or mold with a large-scale 3D sand printer. The mold is printed in an artificial sandstone material in multiple sections that are joined together. Compared to regular concrete 3D printing, which prints in thick layers, this process is able to create much more precise structures.

The structure took about two weeks to harden before it was installed in the NEST (Next Evolution in Sustainable Building Technologies), which is the world’s first modular research and innovation building that ETH uses to test new energy and construction technology.

The roof was printed in 11 segments. installed with a crane, and the end product turned out pretty cool.

More in Manufacturing