To prevent a carriage from falling down when starting and stopping it, by stabilizing a self-standing state on the carriage, in baking by being put in a kiln together with the carriage in a state of self-standing at a specific interval on the carriage, in a plate roof tile of forming a recessed part fittable with the hooking part tip on the surface side of a roof tile end by projecting a hooking part hooked on a sash bar when laying a roof tile on the roof tile end of the roof tile back.

When laying the roof tile 11 on the roof tile end of the roof tile back of the plane roof tile 11, the substantially triangular hooking part 12 hooked on the sash bar is projectingly formed on both sides of the roof tile end. While forming a recess 13 of a recessed shape by a pair at a specific interval between the hooking parts 12, when stacking the roof tile 11 on the roof tile end of the roof tile surface, a recessed part 14 fittable with a tip part of the hooking part 12 is formed by a pair in a place corresponding to the hooking part 12. A projection part 16 fittable with the recess 13 is formed by a pair in a place corresponding to the recess 13 in a flashing 15 of the roof tile surface.