What is OSB?

Oriented strand board.
Oriented strand board.

­You've been hanging around the lumber yards lately because you need wood for one of your do-it-yourself projects. You haven't settled on one type of wood yet, but in talking to experts and other homeowners, something has stuck in your ear. OSB. You've heard this acronym around town. What is it, you ask? While it is a widely used acronym, specifically for ocean groups and religious organizations, for our purposes OSB stands for oriented strand board.

Oriented strand board was created in the late 1970s as inventors extended the use of waferboard. It differs from other wood-scrap products because its long strips of wood are placed strategically rather than randomly. That's where it gets its name, since the strands are "oriented" as a whole [Source: OSB Guide].

Manufacturers of OSB engineer their product to match a performance-rated scale. Manufacturers want to make sure their product is strong, ­multifunctional, uniform and workable. It comes in various sizes, usually ranging from a quarter-inch (6 mm) to three-quarters of an inch (18.5 mm), though customers may put in special size requests.

­OSB uses the wood from trees that grow quickly and sustainably, like aspen poplar, southern yellow pine and mixed hardwood species. The process of making OSB involves cutting the logs into strands that are then dried, organized an­d treated with wax and binders. To form panels, these strands are grouped into big sheets and pressurized at a high temperature.

OSB has come into fashion as a product with the same purpose and function as plywood -- so OSB and plywood compete in the marketplace. Click to the next page to hear whether experts vote for OSB or plywood in the battle of what is the best product for construction.