In wood products, such as parquetry, cabinetry and furniture, some of the performance criterions are related to moisture transfer between their different construction layers. Non homogenous moisture transfer usually results in the product’s deformation . Engineered Wood Parquet Flooring (EWPF) is an important case, which presents non homogenous moisture transfer due to its utilisation in service. Many types of varnish are available on the market. Physical properties of those varnishes such as hardness and abrasion resistance are readily available from the manufacturers. No data on water vapour diffusion is available, so this study is focused on this specific topic. Water vapour coefficient was determined for 6 commercial and industrial varnishes. These values will be used in further modelling work on EWPF.