A vehicle body having an external body sheeting comprising opposite sides and a roof and having an internal floor extending between said sides, wherein, as viewed in a transverse section of the vehicle body, both sides, above a level of said internal floor, and said roof each include a plurality of elongate extruded metal plates forming said external body sheeting, said plates being elongated in a longitudinal direction of the vehicle body and having integral structural ribs extending in the longitudinal direction of the vehicle body on inner faces of said extruded metal plates, and wherein said extruded metal plates are welded together at weld lines extending in the longitudinal direction of the vehicle body.