The anti-skid resistance of six coatings (Alfa, Beta, Gamma, Lambda, Mu and Theta) designed for outdoor wood flooring were tested in chestnut (Castanea sativa Mill.) and pine (Pinus pinaster Ait.) using a Portable Skid Resistance Tester according to standard ENV 12633. Film thickness, coating retention level, and presence of mineral particles were determined for each coating. Furthermore, the liquid water absorption coefficient of chestnut was determined in accordance with standard UNE-EN 1609, to relate all parameters.The highest value of skid resistance in both chestnut and pine was obtained with coating Mu (49.75) and coating Gamma (53.16), respectively. Film thickness and coating retention level were consistently higher for pine than for chestnut. Gamma presented the highest presence of minerals. For chestnut the absorption coefficient of liquid water in the tangential direction was 0.0056 ± 0.0010 kg·m-2·s-0.5, considerably lower than the value found for pine: 0.011 kg·m-2·s-0.5. The different performance of the system wood-coating, and consequently the anti-skid resistance, was attributed to the absorption properties of the different species
