Oriented Strand Board (OSB) is manufactured from sustainable, fast-growing trees such as aspen poplar, southern yellow pine, mixed hardwoods, and other suitable species.
Logs are cut to length, debarked, and processed into strands ranging from 3 1/2" to 6" long and approximately 1" wide.

 



The strands are dried, sorted, and mixed with wax and a waterproof exterior-type binder and formed into large continuous mats. These mats are oriented in cross directional layers for increased strength, then pressed at a high temperature and pressure to form panels.
 

The strands are oriented in layers during the forming process so that strands on the panel surface generally lay in the direction of the panel’s length. The inner layers may be randomly oriented and/or cross aligned like the veneer layers in plywood. The longitudinal arrangement of the strands in the surface layers increases the strength and stiffness of the panel in the direction of the alignment.