Oriented strand board (OSB) is a type of engineered wood similar to particle board, formed by adding adhesives and then compressing layers of wood strands (flakes) in specific orientations.
OSB is a material with favorable mechanical properties that make it particularly suitable for load-bearing applications in construction. The most common uses are as sheathing in walls, flooring, and roof decking. For exterior wall applications, panels are available with a radiant-barrier layer pre-laminated to one side; this eases installation and increases energy performance of the building envelope. OSB also sees some use in furniture production.
Oriented strand board is manufactured in wide mats from cross-oriented layers of thin, rectangular wooden strips compressed and bonded together with wax and synthetic resin adhesives.
OSB panels have no internal gaps or voids, and can be water-resistant, although they do require additional membranes to achieve impermeability to water and are not recommended for exterior use. The finished product has properties similar to plywood.
While OSB does not have a continuous grain like a natural wood, it does have an axis along which its strength is greatest. This can be seen by observing the alignment of the surface wood chips.
All wood-based structural use panels can be cut and installed with the same ease and types of equipment used with solid wood.
Five grades of OSB are defined in EN 300 in terms of their mechanical performance and relative resistance to moisture:
– OSB/0 – No added formaldehyde;
– OSB/1 – General purpose boards and boards for interior fitments (including furniture) for use in dry conditions;
– OSB/2 – Load-bearing boards for use in dry conditions;
– OSB/3 – Load-bearing boards for use in humid conditions;
– OSB/4 – Heavy-duty load-bearing boards for use in humid conditions
Size: 2500 x 1250 mm
Thickness: 8mm, 9mm, 10mm, 12mm, 15mm, 18mm, 22mm, 25mm