The Digital Twin (DT) approach is an enabler of data-driven decision making in Architecture, Engineering Constructions and Operations. Various open data models that can potentially support the DT developments, at different scales and application domains, can be found in the literature.However, many implementations are based on organisation-specific information management processes and proprietary data models, hindering interoperability. This article presents the process and information management approaches developed to generate a federated open data model supporting