The purpose of this study is to investigate whether rooftop greening remained or disappeared in public facilities with rooftop greening, and to consider the life cycle of rooftop green spaces. The cases were collected from the journal of Shin-Kenchiku and technical books, and included cases built before 2001, when the greening of rooftops became compulsory by Tokyo's regulations. Among the 96 cases of public facilities with green roofs, 86 cases in which both the building and the rooftop green space were unchanged, 6 cases in which the building existed but the rooftop green space disappeared, and 4 cases in which the rooftop green space disappeared due to the disappearance of the building were identified. The presence or absence of rooftop green spaces depends largely on whether the building is demolished due to its age or not. And the rooftop green spaces can be removed due to safety, management or cost issues. On the other hand, the movement to protect not only buildings but also rooftop green space by designating it as a cultural asset was confirmed and proposed as one of the measures to exist of rooftop green space for a long time.
