Compared to other assets, buildings have a significantly longer service life. Nevertheless, buildings are often demolished before they reach this point. The reasons for this have not been scientifically researched. A research project at TU Dresden is endeavouring to gain a comprehensive and differentiated overview of the factors that lead to premature building demolition, with the overarching aim of expanding knowledge about extending the useful life of buildings. As part of the project, statistical data on building demolitions in Germany was analysed. The results on the development of demolished and converted buildings in terms of total number, owner, year of construction and cause will be presented in this article.