The historical-constructive study of a building is a key instrument that allows to establish the evolutionary sequence of its uprising, taking care of all the historical facts related to the building and identifying its constructive phases. This study, in which the bibliographical and documentary sources are interwoven with the visual analysis of the real estate and its surroundings, offers data of absolute chronology and the possibility of establishing hypotheses as truthful as possible, which help to interpret the building and its evolutionary periods. The concept "reuse" implies the recovery of a historic building, his putting in service and value, to reuse it granting a habitability and functionality to its spaces. In this research has been analyzed, as an example of application of these two instruments, the Historical Heritage of the University of Granada.Departamento de Expresión Gráfica Arquitectónica y en la Ingeniería. Universidad de Granad