<P>PROBLEM TO BE SOLVED: To provide a rooftop greening method which can be easily practised using lightweight materials at a low cost. ??<P>SOLUTION: The rooftop greening method is carried out by spreading all over a rooftop, greening panels 51 which are formed by fitting a lattice frame 45 into a second water tank 42 made by raising the peripheral edge 41 of a waterproof material 40, and inserting blocks 14 with water retaining function into recessed parts 69 of the lattice frame, and laying natural lawn on an erosion control sheet 63 spread on the panels. The block has sizes p and q so as to have a diameter of a circumscribed circle 16 contacting the periphery 15 of the block of 70-420 mm, and a footprint 66 stepping on the natural lawn is made on a joint 68 between the blocks, and a weight of a walker is decentralized on the whole lattice frame 45 of the greening panel 51 so as to stably support the body. A first water tank 30 is formed inside the block, or the block is made by an accumulated body of a flat plate material 25 so as to store water in a gap 18 between the flat plate materials. It is preferable to fill a yarn bundle 22 in the first water tank. The waste of interior materials made of fiber is used for the flat plate material. ??<P>COPYRIGHT: (C)2010,JPO&INPIT ??
