To provide a waterproof structure of a flat roof which prevents unevenness of the flat roof even when a slope plate is foamed secondarily by heating.
The waterproof structure 2A of the flat roof 1A is formed by covering a top face of a slope forming layer 15 forming a drainage slope with a waterproof sheet 19. The slope forming layer 15 is formed of a synthetic resin foamed body. A solid oil layer 25, which is liquidized at the specific temperature that the synthetic resin foamed body is supposed to be foamed, is oppositely arranged in a manner of being in contact with or slightly spaced from an upper surface of the slope forming layer 15 formed of the synthetic resin foamed body. A fusing component fusing the synthetic resin foamed body is contained in the solid oil layer 25.
YAMADA TATSUYA
Yoshinori Shimizu
Hiroyuki Nishimoto