This paper focuses on Systems of Systems (SoS) modeling and architecting. SoS architecting deals with the way that independent components of a SoS can be dynamically structured and can change autonomously their interactions in an efficient manner to fulfill the goal of the SoS and to cope with an evolving environment. In this context we defined a new model called SApHESIA (SoS Architecting HEuriStIc based on Agents) focusing on the environment and its dynamics. We also proposed a cooperative heuristic to control interactions exchanges between components. These contributions are then instantiated to a case study and evaluated through two scenarii. Obtained results are finally discussed and some perspectives are given.