COPENHAGEN (DK) - In 2004, Lundgaard & Tranberg felt that a 450 m2 floor in Jurassic limestone would be just the thing for Charlottehaven, their new luxury hotel building in Copenhagen. But they wanted it in one piece without any silicone joints. This was the starting point for Lundgaard & Tranberg's stone adventure, which has set completely new standards in the use of stone.
With help from Italian stone masons, Lundgaard & Tranberg set out to find a way to make this natural stone dream come true, because until then natural stone floors were normally laid in 6×6 metre slabs. The team ended up creating three layers of flooring. First a foundation of raw concrete coated with thin mortar to make the concrete completely smooth. On top of this they cast a massive 11-centimetre-thick concrete slab and, finally, the layer of natural stone. Every individual layer is smooth – almost slippery. The floating layers of floor transfer movement vertically through the layers, thereby making it possible to create much larger, jointless surfaces than is usually the case.
A couple of years later, Lundgaard & Tranberg took up a new natural stone challenge. The 500 m2 floor in the foyer of the Copenhagen Business School, Kilen, was to be in solid black Finnish granite. This time the shape of the floor was curved like an Alvar Aalto vase. Again they called in Italian help and by playing and experimenting with all the materials they found a new and aesthetically pleasing way of solving this challenge. They brought the big slabs of granite to the hall and smashed them into pieces of various sizes. Then the pieces were put together so that they fitted the curved contours of the floor. The gaps between the chunks of granite were filled with a new kind of granite-based terrazzo mortar and so a 500 m2 floor was laid – hard as a rock and with beautiful patterns.