The printer is called BigDelta and it's the big brother to last year's model, which was only 4.5 meters tall. It's a metal printer, which works a lot like personal 3D printers, using a rotating nozzle/mixer to print structures by adding small bits of materials like clay or metal. Eventually, enough layers add up to form the core of a house.
If engineers could 3D print houses then it would an address a major worldwide issue: by 2030 it's estimated that 4 billion people will have inadequate housing. Automating building houses using a process like this could go a long way to providing shelter for everyone.