While a Knowledge Building community is a student-directed community, instructors play an important role, preparing the cultural, cognitive, and social conditions for the adoption of the Knowledge Building perspective. This study examines how a teaching team, including an instructor and a tutor, can facilitate knowledge building in a blended university course. More specifically, it aims to investigate the impact of the instructor’s and tutor’s interventions on student participation and the differences between them in terms of the quantity and quality of the interventions. The results show the impact of the teaching team interventions in the changes of the Specific Conversational Functions used by the students and highlight that instructor assumed the role of knowledge building activator, while the tutor is identified as a knowledge building facilitator. Practical and theoretical implications of the findings are discussed.