The problem of indoor spaces in buildings has increased. Experts are currently discussing whether one in two German homes could have mould damage. In addition, classic contaminated materials such as wood preservatives, formaldehyde, and fibre contamination are still widespread in older buildings. To save energy, buildings are being constructed more densely, which means that moisture, the basis for mould and bacterial growth, and chemical compounds are not being sufficiently removed. Furthermore, construction is becoming faster, resulting in individual components having less time for drying and outgassing. Chemical connections, physical factors, moulds, and humidity, which are the basis for microbial activity, regularly lead to significant damage potential, which is why lawyers are frequently involved in this issue.