House O, built in the sixties, is located in a classical residential area in Wiesbaden, Germany. A Competition was organized in order to find a concept of how to rebuild and renovate the existing building. The suggested design interprets the local building legislations in an intelligent way. The prescribed roof form is integrated in the whole building through using a uniform material as well for the roof and the façade. The material, copper plate, is chosen in order to get a lively façade image through the patina created by weather conditions. Our aim was to transform the existing building in that way to create a distinct spatial structure but at the same time a variety and generosity. As the centre of the house a doubleheight living room with a kitchen, a dining area and a gallery was suggested. Through that gallery the roof terrace which is placed on the highest point of the building is reached. From here one enjoys a great view over the city, but is protected by the opacity of the railing which functions as a visual cover.