ABSTRACT
Plywood and OSB (Oriented Strand Board) are both made of timber and glue and have good structural strength. OSB is a relatively new product that has lower requirements for the timber raw material than plywood. Quite often these products are equated without considering their moisture properties under conditions that represent their actual installation as exterior sheathing - low temperatures and high humidities in cold climates - or the effect of these properties on the overall moisture performance of structures. A representative amount of samples were used to study the moisture properties and moisture performance characteristics of European OSB and plywood products and a comparison to one North American OSB and one plywood product was done. The results show clearly the moisture performance differences between OSB and plywood products. The products are not interchangeable in all applications and special attention is needed to find the best application in different climate and moisture load conditions.
