A diachronic approach to scan-to-BIM modelling: HBEP protocols for the stratigraphic analysis of the church of San Benedetto in Salerno

In the stratified architectural heritage, managing historical transformation faces a critical digital gap: parametric modeling software, designed for new constructions, lacks native logic to represent the diachronic evolution of historic structures. This paper proposes an operational methodology based on Heritage Building Information Modeling (HBIM), supported by a specific management protocol: the Heritage BIM Execution Plan (HBEP). The originality of this proposal lies in redefining the fourth dimension (4D); instead of planning future construction phases, the temporal vector is used analytically to reconstruct past evolutionary phases, transforming the digital model into a virtual excavation process and a dynamic archive of the historical palimpsest. This methodology was validated on the Church of San Benedetto in Salerno, a complex of high stratigraphic density ranging from Longobard foundations and Romanesque reconstructions to modern functional transformations and the 20th-century “de-restoration” by Ezio Bruno De Felice. The research was structured into four sequential phases: state-of-the-art analysis, surveying through Scan-to-BIM processes, diachronic HBIM environment design, and simulation of conservative scenarios. The results demonstrate that the model transcends mere static geometric representation to become an operative management tool that bridges historical documentation and future conservation planning. This integration of historical data as structured technical information lays the foundation for future heritage interventions grounded in a scientific synthesis of surveying, history, and diagnostics.