A Scan-to-BIM Approach for the Preservation of the Architectural and Archaeological Heritage: the Digitisation of the Complex of San Nicolò Regale in Mazara del Vallo (Italy)

In recent years, Built Heritage (BH) management has greatly benefited from advances in digital survey technologies and the application of Building Information Modelling (BIM) processes for digitisation and preservation purposes. The integration of range-based (static and mobile) and image-based (aerial and terrestrial) survey techniques enables the creation of comprehensive 3D geospatial datasets for BIM modelling. This study presents the Heritage BIM (HBIM) digitisation of an architectural and archaeological complex in Mazara del Vallo (Italy). The site includes two assets: the 12th-century Arab-Norman church of San Nicolò Regale and the remains of a late Roman domus (3rd-4th century C.E.) beneath it, featuring polychrome mosaic floors. This digitisation aimed to provide exhaustive and detailed geometric documentation and create an accurate digital model for conservation and management purposes. Data acquisition combined mobile and static laser scanning with close-range photogrammetry. The final model was obtained through a Scan-to-BIM approach for the church and an integrated Scan-to-Mesh-to-BIM approach for the domus, ensuring accurate representation of both architectural and archaeological elements. This methodology serves as a reference for digitising and preserving similar heritage sites.