To reach their corporate goals housing companies have to recognise, assess and control risks both on a strategic and on an operative level, and to make use of the chances offered, respectively. This is the general purpose of risk and portfolio management. The overall risk of real estate is defined by a complex structure of single risks. To monitor and to control the overall risk efficiently it is necessary to have knowledge of the concurrence of the single risks. Taking the effects between single risks into account so-called ìRisk Chainsî evolve. Focussing the overall property risk the risk chains form a so-called ìRisk Netî. For further analysis the single risks can be categorized as ìStarpointsî, ìmostly internally affected Midpointsî, ìmostly externally affected Midpointsî and ìEndpointsî, depending on their position in the risk net. The paper presents an utility to analyse and assess Risk Chains. The knowledge of coherencies between single risks enables the risk management to identify driving forces and to implement an efficient early warning system. Additionally it becomes possible to forecast the future development of the building stock for various scenarios within the portfolio management, for example for modernization, maintenance or omissive strategies, and to assess the effectively of regulative measures.