The Birth of the Concepts of Multiple Rooftops Greening and its Significance in the History of Rooftop Greening

Abstract

The purpose of this study is to grasp the concepts of rooftop greening and to clarify the birth of multiple rooftops greening and its concepts and significance in history of rooftop greening. Some 157 examples of rooftop greening were collected from technical books and contests and were analyzed from the viewpoint of place of rooftop greens, spatial relations of rooftop green, accessibility to the rooftop greens, mobility between rooftop greens, presence of natural vegetation, water environment and existence of neighboring ground green spaces. The data set was analyzed through cluster analysis and Hayashi's quantification methods typeⅢ and chronological table on the history of technologies and governmental policies. As a result, it was made clear that the concept of greening the rooftop appeared early works in history of rooftop greening. Afterwards, the concept of rooftop green on the intermediate floor also became popular in 1980s and surrounding natural environments were taken into account in 1990s. After the birth of multiple rooftops greening, rooftop greens became closed to the ground, easier to access, connected visually and biologically and improved between the upper and lower rooftops. In the case of Across Fukuoka of 1995, all concepts were introduced. In conclusion, it’s considered that multiple rooftops greening showed the new concept of continuities.