In the European framework, there is a strong drive to develop integrated approaches aimed at understanding and improving the energy behavior of public historic buildings within urban contexts. However, the examples already provided tend to address the issue from mono-disciplinary perspectives, losing the opportunity for a coordinated view. The research suggests a methodology to reach the definition of a three-dimensional database, which incorporates spatial models and energy information, with the final goal of merging heterogeneous information that is useful to interpret the overall framework and to design sustainable development scenarios. The platform achieves GIS (Geographic Information System) and BIM (Building Information Modeling) integration by using the CityGML data model, for supporting multi-scale analyses without break of continuity, ranging from urban to building level. The discussion combines the applicative case with the theoretical background, deepening the role of a solid knowledge framework as a basis for sustainable interventions on public historic buildings. To better explain and test the methodology, a case study on the University built heritage of Pavia is presented and three possible outputs deriving from the database are discussed. The example demonstrates the strength of the approach, which is able to provide a variety of results coming from a unique source of information, ensuring coherence and unambiguousness at all levels of investigation.

The present contribution illustrates the documentation and setting up of a digital database of a portion of Bellisomi-Vistarino Palace in Pavia (Italy), a relevant historical asset due to its artistic value. Despite recent restoration work, there are still disused portions of the complex, including the garden, the loggia and the rooms on the ground floor that overlook it. These portions are the elements this paper deals with. The approach to a small portion of the building is a pilot case from the perspective of a broader work of integral documentation of the whole complex. The aim is to define digital support for diagnostic and restoration planning activities from the perspective to enhance and create a new cultural attraction for the city, using the Foundation of the University of Pavia, already settled in the Palace and their organizational skills and networks. This is achieved by structuring a tridimensional digital twin and database connected to it to monitor the assets and generate digital environments for cultural and touristic valorisation.

This contribution presents a process of documentation and conservation of the built Cultural Heritage, tested on a partially disused case study located in the urban fabric of the city of Pavia. The actions defined led to the design and implementation of a tridimensional Information System obtained integrating data collected across different research areas, reality-based models and with the goal of enriching a tool for the documentation and management historical buildings owned by the University of Pavia. The process of documentation, three-dimensional digitisation, and census of the architectural elements on an urban and-architectural scale defines a tool for standardised analyses on building complexes of the same property and for large-scale planning of monitoring and valorisation activities. The research is based on the use of tridimensional Information System, as one of the indicators of the 2030 Agenda, in line with target 11/11.4, to activate a process of reuse and sustainable management of urban heritage.

HBIM (Historic Building Information Modelling) and Heritage Digital Twins (HDT) are increasingly used to organize geometric, historical, and conservation knowledge in digital environments. While research has advanced modelling accuracy, semantic enrichment, and interoperability, evaluation approaches remain largely focused on technical descriptors such as Level of Development/Detail (LOD), information completeness, and geometric reliability. Less attention is given to whether these digital outputs are effectively accessed, interpreted, used, and maintained within institutional practice. This paper examines how use is currently framed in HBIM and HDT literature and identifies a gap between technical performance metrics and the conditions required for sustained real-world adoption. Based on an interpretive review of recent research, it analyses existing evaluation paradigms and highlights their limitations in capturing operational and lifecycle dimensions of digital heritage initiatives. To address this gap, the paper introduces Level of Use (LOU) as a complementary evaluation dimension. LOU is defined as the extent to which digital heritage models are accessible, interpretable, actionable, and maintained over time within their organisational context. Positioned alongside LOD, Level of Information (LOI), and accuracy specifications, LOU links technical model quality with institutional adoption, long-term usability, and sustainable heritage management.