Quantification of potential damage to objects and infrastructure caused by natural hazard events plays an important role in hazard and risk assessment. In contrast to predictive estimation, it is easier to determine types and extent of damage after an event has occurred. The amount of damage caused by a natural hazard event depends on the characteristics of the process, the endangered objects and surrounding conditions. A total of 14 post-event case studies were evaluated to assess the distribution of damage to buildings, related to the type and intensity of the hazard process. Based on this studies two different methods are proposed to determine the vulnerability of buildings due to floods, debris flows and avalanches. The quantification of vulnerability helps to more efficiently plan mitigation measures for hazard reduction.