How can BIM save the monuments of the past?

BIM, or Building Information Modeling, is well known for designing new structures, but in recent years it is also taking over the world of historic monuments. The HBIM (Historic BIM) model gathers not only the geometric shapes of a building but also historical, diagnostic and monitoring data. Imagine a "digital identity card" for a castle, where each stone is described, its age, the damage it suffered and the restoration measures already taken. A recent review examined 451 studies published from 2008 to 2024, showing how research has shifted from simple 3D drawing to integrating non‑geometric information. Researchers identified three key steps: defining model entities (both shapes and meanings), enriching the model with historical and conservation data, and finally sharing and using this information on site, for example with tablets or augmented reality. The result is a more complete system that helps experts diagnose problems, plan interventions and communicate with the public. In practice, HBIM becomes a bridge between the past and future technologies, making conservation more efficient and transparent.

HBIM relies on a multi‑layer data structure that merges parametric geometry with semantic ontologies. Geometric entities (points, lines, surfaces) are typically represented in IFC (Industry Foundation Classes) formats, while non‑geometric information is encoded using RDF (Resource Description Framework) or XML schemas, enabling interoperability between design software, GIS systems, and heritage management platforms. A critical aspect is defining semantic classes for historic elements, such as "city walls" or "barrel vaults," which include attributes like dating, original materials, consolidation interventions, and deterioration values measured by IoT sensors. Data enrichment leverages laser scanning, photogrammetry, and laser Doppler techniques to generate high‑density point clouds, later transformed into optimized meshes. These meshes are linked to relational databases that store archival documents, historic photographs, and structural analysis results. For sharing, cloud platforms like BIM 360 or Autodesk Construction Cloud provide RESTful APIs that allow real‑time access to updated models, facilitating collaboration among architects, engineers, conservators, and public stakeholders. Interoperability is further enhanced by standards such as COBie (Construction Operations Building Information Exchange), ensuring consistent transmission of operational and maintenance information. Augmented and virtual reality (AR/VR) enable on‑site visualization of HBIM models, overlaying diagnostic data onto real elements, improving structural problem comprehension and citizen communication. Finally, predictive analytics using machine learning can exploit historic datasets to forecast degradation trends, optimizing intervention plans and reducing long‑term conservation costs.