The material properties and life time of cementitious materials depends on both hydration conditions and resistance against chemical attacks during and after the construction of buildings respectively. In this study, experimental setups were developed to investigate the changes of the phase composition with a high resolution during this different time periods of cementitious materials life. They based on X-Ray diffraction methods using intensive synchrotron radiation. This provides a detail view into the dynamics of the hydration processes at early ages and the change of the phase composition due to interaction with common solution.