This paper contributes to a sustainable construction design management approach to increase the successful renovation rate of existing residential building stock. Indeed, coupling BIM with mixed reality can speed up and improve the quality of the renovation design processes, because it can display virtual models of alternative design scenarios superimposed over the existing physical facility. To this purpose, a sample of technicians was enrolled to test the reliability of this technology. A prototype was developed that enables cooperation among stakeholders and the implementation of an efficient workflow. The volunteers carried out real-life tests in a building demonstrator in Caceres (Spain) and filled in two questionnaires with their feedback. The results showed that an MR-based platform can involve interested stakeholders in the assessment of renovation design projects, that speeds up the decision-making process and increases the quality of those projects. Moreover, technicians can master the technology quickly, provided that it is included in the current renovation workflow and some technology gaps are covered. However, the main limitations of this study are that these findings are valid for building renovation design only, and the tests were performed in a controlled, yet full scale, experimental environment. Finally, this paper deals with a few open technical issues, such as the efficient alignment of holograms, transformation of BIM models into a format suitable for mixed reality applications and sharing feedbacks in an on-line repository to foster collaboration.