To solve problems that the existing tile can not cope with a lateral deviation toward a direction of an overlapped part and an engaging insertion part is easy to come off from an engaging projection.

With a tail-side of the tile body 2 turned up, the tile has a hook-shaped engaging projection 9 formed inside of a water-flashing 5 on the tail-side. The engaging insertion part 10 for the engaging projection 9 is provided within a cutout on a head-side while the engaging insertion part 10 is formed integrally on either or both of the tile body 2 and an under-lapped part 4. Contact faces 11, 12, which touchably oppose to the head-side and the tail-side when laid, are formed in such a way that the contact face 11 of the lower disaster-prevention tile 1 is positioned toward an overlapped part 4 from the contact face 12 of the upper disaster-prevention tile 1 when they are laid, so as not to deviate in the direction of the overlapped part. Furthermore, in case the tiles are flipped centering the engaged portion of the engaging projection 9 and the engaging insertion part 10, by providing the engaging insertion part within the cutout on the head-side, the engaging insertion part 10 does not come off from the engaging projection 9 because the outer portion of the under-lapped part 4 placed outside of the engaged portion goes down to abut on the lower tile 1 and does not turn up any further.