How Are Modern Skyscrapers and Ancient Ruins Modeled with BIM?

Building Information Modelling, or BIM, works like a 3D video game for architects: it creates a digital model that stores not only the building's shape but also data on materials, costs and maintenance. For new constructions, BIM is already a solid practice: software provides libraries of parametric objects—windows, doors, beams—that easily adapt to project specifications. Just pick the element, set the dimensions, and the model comes to life.

What happens when we want to reconstruct a historic building, perhaps a Renaissance palace or a medieval church? Here the heritage version, HBIM, steps in. Standard objects aren’t enough: ancient structures have unique shapes, special materials and details you won’t find in a modern library. Experts must create new parametric objects, often starting from laser scans, high‑resolution photos and archival documents. This takes more time and specific skills, because each component must stay true to its historical authenticity.

The study published in *Heritage* compares these two approaches. Results show that modelling a new building follows a linear path, while recreating heritage requires more research and customization. Nevertheless, both methods boost collaboration among engineers, architects and conservators, making it easier to plan restoration works or design new constructions that respect the historic context.

BIM relies on an open data model (IFC – Industry Foundation Classes) that enables information exchange across different software. In a traditional project, parametric libraries contain predefined objects with standardized attributes (e.g., thickness, material, strength class). These objects are generated through geometry‑based algorithms, reducing creation time and facilitating consistency checks.

For HBIM, the main challenge is the lack of precise data. Historic buildings often lack modern technical documentation; therefore, acquisition techniques such as photogrammetry, LiDAR laser scanning, and close‑range laser scanning are employed. Raw data are filtered and converted into point clouds, from which surfaces and volumes are extracted. This information is then fed into an extensible parametric model, where objects are defined by not only geometric parameters but also historical ones (e.g., type of mortar, stone laying method).

An additional complexity layer involves uncertainty management. HBIM models commonly introduce confidence level attributes to indicate measurement precision. Moreover, modeling non‑standard elements—such as pointed arches or barrel vaults—requires advanced mathematical functions (splines, NURBS) and custom scripts (e.g., Dynamo for Revit). These scripts automate complex geometry generation but demand programming skills.

Finally, integrating HBIM data with GIS (Geographic Information System) allows contextualizing the building within its urban landscape and assessing environmental impacts. Interoperability among BIM, HBIM, and GIS is facilitated by open standards like CityGML, enabling coherent exchange of topographic and cultural heritage information. This integrated approach supports more informed decisions during restoration or urban development planning while preserving the building's historic identity.