The physicochemical properties of outdoor moveable artworks are modified by degradative environmental agents and biodeterioration. In many cases, the most effective action or intervention is to replace an artwork with a copy, moving the original into a museum or another more protected place. In general, this process entails moulding of the original and its reproduction using restoration mortars. This study evaluates the possibility of using cyclododecane (CDD) as a temporary barrier film during the moulding of extremely porous stone sculptures and ornaments. For this, samples of a travertine (calcium carbonate rock) called Tosca Rocafort were prepared. These travertines, exceptionally porous with numerous cavities, can be percolated in an irreversible way by moulding materials during the process of making a copy. By using a CDD barrier layer, the pores are sealed without losing the texture of stone substrate, and at the same time the silicone moulding material is prevented from penetrating the porous stone. To solve the problem of an affinity between the CDD and the silicone (both of which are non polar materials), several polar substances (4% agar-agar in water and pure latex) were tested as an intermediate insulation layer. This proposed method, based on a system of layers with different polarities, allowed us to isolate and protect the porous stone from the silicone elastomer, which is the cause of irreversible stains on stone substrates during mould-making. As an isolation layer, agar-agar proved unsatisfactory as it formed heterogeneous layers with low physical resistance, resulting in residues of moulding materials on the stone suface. In contrast, latex created homogenous layers while transmitting all details of the surface of the original work – and without leaving residues. The presented multi-layer system for moulding of porous materials has a number of advantages that make it appropriate for conservation and restoration work: good film-forming properties, very low toxicity, and ready reversibility (due to the ability of CDD to sublimate). The CDD film remains in place for long enough to allow the silicone moulding material to become vulcanised. However, it is easily removed through sublimation, which means that no intervention (possibly damaging to the surface of the stone) is necessary to remove the barrier layer. We conclude that CDD is a suitable temporary barrier material on porous stones, creating a homogeneous, impervious and inert film.