| 摘要 |
PROBLEM TO BE SOLVED: To ensure the prevention of water infiltration from the superposed part of surface plates, and allow an easy work for arranging a plurality of the surface plates side by side. SOLUTION: A plurality of surface plates 3 are arranged on a roof surface material 6 in such a state as partly superposed along a roof slope direction, and a drainage layer 11 for releasing water to the surface plates 3 in a direction intersecting the roof slope direction is formed on the surface plates 3. As a result, rainwater, even if trying to enter the superposed parts 8A and 8B of the surface plates 3 after a rainfall, is discharged outside via the drainage layer 11. |
