The task of this project was the development of a concept for the roofing and modernization of the sewage plant in S-chanf. Starting point is a large cubic concrete structure and outisde treatment tanks. The concrete corpus does not require any energetic measures and is integrated into the overall concept. Sludge treatment, mechanical cleaning and external use are combined into one element with a homogenous facade. The premises are going to be completely roofed and a natural wooden slat facade enhances the building visually and functionally. The use of wood as main construction material is considered positively because it is a local material and due to prefabrication the construction time can be shortened. Functionally the new concept comes with several advantages: high weather protection, ventilation of the facade, sun protection available, little effort in removing snow.