The Federal Agency for Cartography and Geodesy (BKG) provides 3D-Building models for Germany. The data come in a City-GML (geographical markup language) format, locating every building throughout Germany and providing information such as its ground plan, height, and the building’s purpose. I will provide an overview on the data, its coverage and limitations, as they are available for everyone within the DIW. Because of the data format, reading the data is not trivial. Thanks to the Research Infrastructure Department and their help; we are able to access the data in a convenient way. I will present first ideas for research using this data in the context of small area estimation and weighting.