Building acoustical auralisation is useful in many fields of applications. It can be used in the design of buildings or in teaching. Students of acoustics, architecture, and civil engineering get an impression of the acoustic effects of different materials and construction methods immediately. In research, it allows the execution of listening tests without having to carry out extensive measurements and recordings. Thus, it is a useful tool to improve the quality of reference curves for single number ratings. In this thesis, an algorithm for auralisation of airborne and impact sound insulation in buildings was developed, verified, and applied in several areas of research. The description of the basics comprises prediction methods for sound insulation in European countries and two detailed methods for calculation of sound insulation in a 2 room situation as well as basic principles of auralisation. After a detailed description of the algorithms for auralisation of airborne and impact sound insulation and a verification, 2 applications concerning speech privacy and the influence of background noise on mental processing show the practical relevance of the method.