Oriented Strand Board (OSB) is an engineered, mat-formed panel product made of strands, flakes or wafers sliced from small diameter, round wood logs and bonded with an exterior-type binder under heat and pressure.
OSB panels consist of layered mats. Exterior or surface layers are composed of strands aligned in the long panel direction; inner-layers consist of cross- or randomly-aligned strands. These large mats are then subjected to intense heat and pressure to become a "master" panel and are cut to size.
Strand dimensions are predetermined and have a uniform thickness. The majority of Structural Board Association (SBA) member mills use a combination of strands up to 6" (150mm) long and 1" (25mm) wide.
OSB's strength comes mainly from the uninterrupted wood fiber, interweaving of the long strands or wafers, and degree of orientation of strands in the surface layers. Waterproof and boil proof resin binders are combined with the strands to provide internal strength, rigidity and moisture resistance.
OSB, as a performance-based structural use panel, is recognized by all major U.S. model code agencies through the adoption of DOC PS 2, Performance Standard for Wood-Based Structural-Use Panels. Certified to CSA 0325, Construction Sheathing, or CSA 0437, OSB and Waferboard, OSB is accepted in the National Building Code of Canada, certified to EN 300, Oriented Strand Boards and recognized for structural use in Europe and certified to meet the JAS standard for structural panels in Japan.
Members of the Structural Board Association are specialists in OSB and are committed to "Total Quality" manufacture of OSB or waferboard for use in North America and overseas.
Click here to take a visual tour of the OSB manufacturing process.