Abstract: The insulating panel has a honeycomb structure core made of repulpable material and two skins sandwiching the core. Insulating particles can be used in the cells. One or both skins can have a layer of thermally insulating material, such as expanded polystyrene, for example. Nonetheless, by incorporating some repulpable components, the insulating panel can be made more interesting to recycle than an all-expanded-polystyrene insulating panel. The process of making can include driving a honeycomb web made of repulpable material and having a first and a second opposite faces, and adhering a first skin web to the first face. Optionally, the cells can be filled by insulating particle. A second skin web is applied to the second face.