Weather processes damage stone buildings and even the strongest stone does not last forever. In the EU project “Nano-Cathedral” research is being conducted at Vienna University of Technology that hopes to understand how such damage progresses and prevent it in the future. After understanding the natural decay processes, these have to be mimicked by artificial ageing techniques. These procedures, amongst others, are carefully studied at the facilities of the X-Ray centre of Vienna University of Technology. Additionally, the decay patterns are treated by newly engineered Nano-consolidants in order to regain the original properties of the stone.