The world famous furniture and interior design group Poltrona Frau approached us with the request to design and develop a new floating stair concept for their show room in Miami. It had to be something new in terms of materials and impact on the surrounding space. Since Poltrona Frau has very clear lines and minimalistic looks in their new show room they were very excited from the very beginning about the cantilevered stairs in concrete. This was exactly what they needed to complete the design concept. In the following weeks we have tried various concrete mixtures and artificial materials like fibers and plastic and epoxy glue to create a material which is strong enough to bear the loads of commercial use and at the same time does not lose its filigree character. Finally we ended up with a mixture of materials which satisfied our and the clients demands in terms of tread thickness, surface structure and load bearing characters. The concrete tread can be produced with just 6cm thickness up to 100cm width and with 8cm to 10cm thickness up to 150cm width, which is the most common width for commercial stairs. The new Miami Show room will open the doors by beginning of March and our stair is the focal centre point of the interior. It will host the Poltrana Frau Brands Capellini, Alias and Cassina lighting. Polrona Frau will is intending to open up two more show rooms in the USA and Siller stairs will be on board to design the interior stairs also for those centre points of modern interior and furniture design www.sillertreppen.com