HBIM modeling presupposes a series of methodological and content questions depending on the type of historic building being investigated. A particular case refers to a multitude of buildings, isolated or aggregated, that sprinkle our territory that do not stand out for their valuable architectural characteristics abandoned for different reasons and turned to ruins. This building category retains a valuable judgment when the typological constructive characteristics are recognized as explanations of “making architecture”, strongly linked to a place and to a time and that are worth preserving. The study of a ruin as a building typology involves various issues starting from the survey, both in terms of structure stability and room accessibility, and in terms of survey techniques to be used to acquire geometries that have lost their original conformation. The loss and deformation of the shape are therefore the main obstacles in the reconstruction of the historical evolutionary phases, fundamental for the definition of a recovery project that respects the nature of the building, now in a state of instability. Informed digital models, soon mandatory by law in most building processes, applied to the ruins thus become not only a means of documenting, cataloging, and communicating the built heritage but, above all, a tool that serves the project.