PURPOSE: To prevent the corrosion and rain-water leakage of a batten from being generated due to condensation by arranging salient portions for leading the water drops of the condensation on the rear side surfaces of roof tiles, downward, and by forming water inducing passages for collecting and inducing the water drops in the lower end direction between the salient portions.

CONSTITUTION: Roof tiles 1 are arranged with the partial sections put together to be roofed with, and on the rear side surfaces 5 of the roof tiles 1, salient portions 10 for leading water drops 7 of condensed water 8 downward are arranged, and between the salient portions 10, water inducing passages A for collecting and inducing the water drops 7 in the direction of a lower end 4 are formed. Then, the condensed water 8 is turned into the water drops 7 and flows in the direction of the lower end 4 along the salient portions 10, and in this case, the water drops 7 near the water inducing passages A are induced in order, and so the corrosion and rain-water leakage or the like of a batten can be prevented from being generated due to the condensation 8.