From Geospatial Data to HBIM of Romanic Churches in Sardinia: Modelling, Check and Validation

The information management of historical buildings through BIM methodol-ogies presupposes not only the collection of data and information relating to geometric shape and technical parameters of the component elements, but more generally the identification of those semantic values, which make it part of the historical-cultural heritage shared in a specific context. It is there-fore essential that the modelling purposes and information exchange re-quirements are explicitly defined in relation to the specific BIM Uses re-quired. This contribution proposes a process of geometric validation of in-formation models of buildings of high morphological complexity imple-mented through Scan-to-BIM procedures. Through a controlled and interop-erable workflow, a chain of software applications is stated to define the level of geometric accuracy (LOA) of the information model with respect to the numerical model derived from the point cloud. Two case studies related to H-BIM modelling of historical monumental complexes dating back to the Romanesque period in Sardinia (Italy) are illustrated: the churches of Sant'Efisio in Nora (Cagliari) and Santa Maria del Regno (Sassari). In the discussion of the results, the need for a prior definition of modelling strate-gies in relation to the expected BIM uses is highlighted.