The invention concerns a tipper body (4) comprising an underframe (6) directly mounted on the frame (2) of the vehicle (1) and a skip (7) itself comprising a platform body (9) forming a floor. The platform body (9) is made in one single moulded composite piece comprising an assembly of reinforcements embedded in an organic matrix for picking up and distributing the point-to-point loads of actuators (8) and of the tilting articulation (17, 18), and rigidifying the platform body. One of the structural reinforcements is a beam including a foam web enclosed in at least a fibre wrap. The invention is useful for lightening loading structures, particularly for small commercial vehicles, providing them with greater durability and making them less noisy.