Objectives, originality and novelty of the project In order to reduce the economic, environmental and energy impact of building usage it is necessary to improve the performance of the envelope as well as the HVAC systems so as to exploit local renewable energy. However, the more the design aims for high performance, the more the interactions and coupling effects between the building, its environment and the conditions of use are important. Real consumptions and comfort level depend on the way the building is controlled while it gets more and more difficult to define in an intuitive way an optimal building management strategy. In order to ensure the best thermal comfort to occupants without deteriorating the actual performance of the building, the later should constantly adapt to changing use and environmental conditions based on a prediction of its future state and the forecast of variables like energy price or CO2 emissions associated with energy use, etc. PRECCISION project aims at bringing scientific and technical solutions to improve building energy management systems in order to fulfill these requirements. We will develop new methods and tools to analyze in real-time the building’s energy behavior and to control it, either by acting directly on the systems configuration or by providing the user or the building manager with useful information about the building state. The project PRECCISION project aims at developing software components including modeling tools based on building physics, model reduction techniques, identification and inverse modeling methods and optimization algorithms. Some developments will also concern a software front-end in order to provide useful information to the occupant or building manager, involving them in the control loop. In order to demonstrate the feasibility, the developed software tools and associated hardware will be implemented and tested in real life buildings. Three experimental platforms will be used: an unoccupied house for experimental validation needs (INCAS research platform); an occupied well-instrumented building (the PREDIS/MHI platform); finally, an occupied retrofitted apartment building that will provide useful information about the acceptability of the impact on the inhabitants. Organisation and Consortium The consortium brings together building physics specialists (Armines CEP, I2M TREFLE, CEA INES, IFSTTAR), a company specialized on multiphysics systems modeling (LMS IMAGINE), two teams in the areas of software frameworks for optimization of thermal and electric systems (Grenoble-INP), the VESTA-System startup specialized on software solutions for energy system optimization and the DeltaDore group, service and software supplier for energy management of buildings.