Concrete, the backbone of modern construction, comes at a massive environmental cost. Now, Autodesk Research and Additive Tectonics are looking to change that with an experimental new method that 3D prints slabs out of “econitWood” (a wood waste and mineral mix), swaps steel for flax fibers, and pours in geopolymer mortar that’s as strong as it sounds sci-fi. The result? Floors that are lighter, stronger, and a lot friendlier to the planet.