The aim of this work was to investigate the mechanical and barrier properties of starch-based, low-weight coatings with a non-conventional hydrophobic clay tiller commonly used in plastic industry. A commercial linerboard was coated with two different types of potato starch- based coatings; one based on a conventional oxidized starch, while the other on a hydrophobic modified starch The coated linerboards were examined using scanning electron microscopy and characterised with respect to water absorption, water vapour transmission rate, glass transition temperature, tensile stiffness and wetting by water. The results obtained indicate that hydrophobically modified clay commonly used in the plastics industry may be used as a coating additive to improve liquid water and water vapour barrier properties of paper products.