Printing Buildings in Synthetic Marble
A gazebo structure created using the D-Shape printer, by Monolite UK.
3D printing is a widely adopted tool used to make prototypes in materials such as corn starch, plastic, and metal. More and more, though, 3D printing—also called "additive manufacturing"—is being targeted for the final product itself. Although this makes sense for small products such as jewelry, buildings pose much greater challenges for 3D printing due to their size, complexity, and necessity for structural reliability.
The University of Southern California collaborated with NASA to produce the Contour Crafting process, an experiment to "print" concrete buildings in multiple layers of material using a large gantry crane with a robotic armature. The researchers’ goal was to cast concrete as a powder, to be combined with water immediately prior to extrusion.
UK-based Monolite has been developing its own technology to print buildings. Creator Enrico Dini uses two simple materials—an inorganic, non-epoxy binder and ordinary sand—to produce large-scale structures in a single pass, from foundation to roof. When the liquid binding agent combines with the sand, a kind of hard, synthetic marble is formed. Dini claims that the new material is structurally superior to portland cement and requires no reinforcing. Monolite plans to sell small building-sized printers, the first of which will be able to produce the equivalent of 12 two-story buildings in a year.
In many ways, the ability to print buildings seems too good to be true: no more formwork, carbon-emitting portland cement, steel reinforcing, contractor error, or contractor injuries; and the ability to fabricate incredibly complex shapes with a 10 mm tolerance and no wasted material. However, this technology is still nascent, and many challenges remain regarding in-situ casting, building systems integration, and liability. Nevertheless, based on the many notable benefits, the 3D-printing of buildings will only be increasingly attractive to architects and other construction industry players.