To develop a composting facility of a structure to kick up a roof used for the purpose of composting organic wastes.

(1) The facility has the structure that a roof section 4 is kicked up in a longitudinal direction to make its flanks open, making it possible to transfer compost materials 3 in and out and to turn these materials by using working vehicles 12 and 13 in spite of the least facility area and roof height to cover the compost materials 3. (2) The roof section 4 is rotationally movably supported at its apex and is constructed to be pulled up with wires 6 by means of reduction gears 5 such that the roof section 4 can be pulled up by using the driving power of the reduction gears 5. (3) The roof section 4 is covered to envelop aggregate from the outside surface and inside surface by transparent films 41 and 42 and is constructed to function as a thermal insulating layer to transmit solar radiation and to prevent the inner air containing gaseous ammonia from coming into contact with the aggregate. (4) The water of dew condensation produced on the inner side of the roof section 4 is recovered together with the gravel juice produced from the compost materials 3.