Abstract: A leaktight covering, in particular for an industrial building, includes a loadbearing element adapted to be fixed to a framework element of the building, a layer of an insulating material arranged on the loadbearing element, and a cladding covering the layer of insulating material, with connection structure holding such three components assembled together. A first member is used, on the one hand, to ensure fixing of the loadbearing element to the framework element and, on the other hand, forms part of the connection structure. A second member is linked to the first member and to the cladding. In a first embodiment, the first member is a screw screwed into the framework element, and the connection structure includes a hollow, cylindrical intermediate piece, a bottom of which is fixed to the loadbearing element via the screw.