The aim of this thesis in architecture for sustainability is to propose a BIM-based method that can be integrated with other disciplines according to a multi-level approach to design (Whole Building Design) and capable of involving various specialists (structural engineers, energy experts, restorers, economists, etc.), who must share economic optimisation objectives together with the constraints of preserving assets of historical, architectural and environmental interest. The method is based on the use of BIM and technologies such as GIS, Digital Twin and IFC interoperability to simulate design alternatives according to costs and different usage or investment requirements on multiple scales. The thesis explores the potential of BIM in connecting specialists and supporting intervention decisions, considering economic and financial feasibility in relation to potential buyers interested in use and/or investment value.