T-Mobile 2, Bonn, DE

A service building, a canteen and storage areas were built for T-Mobile on a site with 74,000 square metres in 2007. We produced the façade elements with an acidified structured finish for this building project.

We were already brought on board during the project’s planning phases by the Cologne-based Schmitz Architekten firm of architects. A sophisticated sandwich façade with a good finish of exposed concrete was to be installed in front of the supporting structure that had been realised with cast-in-place concrete. We consequently produced façade elements for a area of around 22,000 square metres in total. We developed four different shades of colour (two shades of green and one each of anthracite and white) as requested by the architects.

The top layer of fine mortar was removed from the surface of the concrete using acid during production to create a sandstone-like finish. The colours were realised mainly with the help of cement slurries and pigments, i.e. using the fines in the concrete because this method only exposes the coarser aggregates to a very limited extent.