The research purpose aims to develop and analyse a workflow centred around decay representation within a selected BIM modelling environment. It involves conducting a comparative analysis based on accuracy criteria, process complexity, estimation of processing time, and the advantages and disadvantages of different methodologies explored. The objective of this research is to enhance the modelling process for building description by incorporating the representation of decay verified within the 3D model. The workflow proposed starts from a digital survey of a cultural heritage architecture and subsequent BIM modelling that generates significant interest within the scientific community not only from the advantages offered by the BIM process but also from the challenges encountered. One challenge relates to the complexity of modelling and unresolved interoperability issues between different NURBS and BIM modelers. Another challenge involves the time wasted in striving for a high degree of accuracy in existing models. Additionally, difficulties arise in uploading data encompassing historical information about the monument, previous renovations, material conditions, and overall state of the structure. Among these challenges, representing the decay state of an artifact within a model remains largely experimental and the paper will demonstrate the efficacy of its representation into a BIM model.