The Aparthotel Longhin stands at the foot of a mountain in the Swiss village of Maloja. With its exposed-aggregate concrete facade and compact polygonal form, the building is reminiscent of an erratic block and well integrated into the scenic ­landscape.

The external skin, suspended from the load-bearing outer wall, was poured section by section on site. For this, an elaborate process was developed in a series of practical trials and laboratory tests. By applying a retarding agent to the outer ­shuttering, the surface remained soft until after striking the ­formwork. In this state, it was possible to remove concrete with a high-pressure jet of water to such an extent that exceptionally large stones protrude in a relief-like form, but without washing them out completely.