To always connect a down pipe, installed along a post, to gutter frames of a plurality or a large number of the same types of car ports having roofs in different pitches.

A fixed pedestal 4 is installed on the lower surface of the gutter frame 3 of a roof 2, and the down pipe 7 is connected to the fixed pedestal through an attachment 5 and a drain elbow 6. The fixed pedestal 4 comprises an arcuate surface 41 on the lower surface so as to project therefrom, and the attachment 5 comprises an arcuate surface 51 with the same radius of curvature as that arcuate surface so that the upper surface is recessed. Therefore, the attachment 5 is rotatably and slidably installed on the fixed pedestal 4. The gutter frame 3 is connected to the down pipe 7 while the distance between the connection tube 61 of a drain elbow 6 connected to the attachment 5 and the down pipe 7 or a down pipe connection part 71 provided thereto is kept constant.