The DigiBUILD project explores the potential of Digital Twin (DT) at the building scale. With a view to establishing a solid groundwork for a sustainable built environment, DigiBUILD develops an open, interoperable, and cloud-based toolbox to collect data and trigger data-driven approaches. By exploiting the value of data collected from IoT sensors, the DT will enable innovative services for reducing energy consumption, improving comfort, and assuring user safety. In this perspective, building managers (e.g., facility managers, sustainable managers, human resources, etc.) can monitor building performance in real-time, carry out forecasting evaluations, and make decisions based on data. The Focchi Headquarters, including both office and factory spaces, is used as a case study for the development of the Digital Twin (HE_ GA 101069658 )