protect the house against the weather, come in different variants. Slate dominates to this day in Westphalia, the townscape in the southern mountain region, namely the Sauerland, the Siegerland, and the Märkischer Kreis. There, the raw material was mined in quarries.

The slating of vertical walls was an effective means to protect a house in the rainy mountain zones against driving rain. At the same time, this form of cladding was also gladly used to give the house special decoration. This led to the development of so-called decorative slatings. These are technically and craftily more complex to produce than roof coverings. With regard to the high costs, the exterior wall slatings were mainly limited to the weather-exposed sides of the house.

The Remberg Hof (farm) from Finnentrop-Fretter, Olpe district, is a typical example of the extensive and at the same time diverse use of slate on exterior facades. Here, not only are the roofs covered with slate, but individual exterior walls are also clad with it. After the house was brought to the open-air museum in whole parts (whole-part translocation), it was rebuilt here until 2015. The last remaining task of the reconstruction is the restoration of the slate cladding of the west gable.

Slate is a metamorphic rock that formed about 345 to 400 million years ago from fine-grained clay-silt masses. It is a particularly durable material and yet easy to work with due to the plate-shaped minerals it contains. Its colour is usually dark grey to grey-blue, but changes over the years.