The world’s tallest 3D-printed building, the 30-metre Tor Alva (White Tower), has been completed in Switzerland using a unique robotic construction technique.

Built in the sparsely populated mountain village of Mulegns, the project was a collaboration between researchers at ETH Zurich and cultural foundation Origen.

The White Tower consists of 32 sculptured white concrete columns that rise up over four storeys, becoming thinner and more branched as the tower extends upwards. The branches fan out like a tree to create a domed space at the top.

Instead of relying on traditional concrete formwork, the construction team opted for an additive manufacturing process, whereby an industrial robot applies the concrete layer by layer into free-form elements without any supportive casting moulds. The design is based on complex algorithms that generate the ornamental and the structural aspects at the same time.

A special kind of concrete was developed especially for the project – it had to be soft enough...