Review 2020.2 – The Transformation of CORSO

From a cinema to a “floating house“, the new striking CORSO building on the outskirts of St. Gallen’s old town combines art, culinary and work together under one roof – after more than 50 years of cinema operation, the building at Brühlgasse 37 has been converted into the headquarters of the company Senn. In addition, the former gastronomic co-use has been reactivated with the opening of the new Corso restaurant. The realisation of the conversion project was a real engineering adventure for us, which we proudly look back on. With consideration for the significance of the existing building (1961) by architect Willy Schuchter, the architectural concept by Rothen Architektur provided for largely preservation of its appearance. The construction measures concentrated on the ground and first upper floors, which were initially completely dismantled, and on the two basement floors. The upper part of the building with the existing office floors was left in its original condition.

The structural engineers from Lüchinger+Meyer achieved a remarkable coup, particularly in the planning and execution of the dismantling work. Complex support measures had to be taken in advance to secure the upper storeys to be retained. Under limited space conditions, new micro pile foundations were set in the existing structure and a large number of ceiling recesses were made, through which the support columns were then passed in small assembly steps. Only when the transfer of forces to the supporting structures was secured could the demolition and excavation work begin.
The building’s structural history can still be experienced to some extent today. For example, the uncovered column of the existing joist of the interception ceiling above the former cinema hall as well as the visible coloured adhesive reinforcements are remaining testimonies of the reconstruction that promote the understanding of the existing static structure.

(Photos new building: Daniel Ammann)