People usually spend most of the time inside buildings. Therefore, it is necessary to reach an optimal thermal comfort situation since thermal comfort has a direct effect on people's productivity. The use of appropriate control strategies can highly contribute to this purpose. Usually the own people's influence is not taken into account at the time to maintain an optimal thermal comfort. People enter and leave the building following certain pattern which is repeated from one day to another. This paper presents a Repetitive Control (RC) approach which can counteract this periodic behaviour. This controller anticipates the effects produced by the entries and outputs of the people. Moreover, this controller is complemented by a feedback controller in order to cancel the non periodic disturbances. Simulation results obtained from the application of this control strategy to a characteristic room of a building are included and commented.