Stair G. is the first project to be realised using the Selective Paste Intrusion (SPI) method. As the central architectural element of a private house overlooking Lake Garda, the staircase extends over two storeys and a total height of ten metres. The 3D printed core of lost formworks allows the steps to cantilever from it, thus separating them from the surrounding interior walls and enabling a crucial separation for sound insulation.  

The load-bearing element of the staircase consists of 18 SPI-printed boxes that act as lost formwork. Weight optimisation to reduce the material used and assembly aids in the form of recesses for inserting the steel steps were already included during the planning stage. On the construction site, the steps were simply placed in the inserts provided in the respective formwork element. The individual elements together with the steps were then placed on top of each other, reinforced and cast at the same time.