"Oriented strand board (OSB) is a popular—and versatile—engineered wood product that is incredibly strong and water resistant."
From exterior wall sheathing to cabinetry, plywood serves countless uses and is one of the most ubiquitous building materials, especially here in the Pacific Northwest. With so many uses and different types of plywood available, it’s important to know your options, understand the material, and pick the right product for your project.
For our Plywood Series, we’re joined by T.R. Cauthorn, Panel Sales Manager at Hampton Lumber, a leading sustainable lumber producer based in Washington and Oregon and one of Dunn Lumber’s long-standing suppliers. With nearly 30 years spent with Hampton Lumber, plus experience working in mills and forests with Georgia Pacific, T.R. is a plywood expert.
In today’s episode, T.R. explains the differences between plywood and oriented strand board, commonly called OSB. OSB is a popular—and versatile—engineered wood product that is incredibly strong and water resistant.
Watch our discussion in the video above, or keep reading to get the highlights.
Difference between manufacturing plywood and OSB
Simply put, plywood is made by pressing and bonding wood veneer sheets together. (Learn more about the complete plywood manufacturing process here.) OSB is made through a similar technique—however, instead of using wood chips as with plywood, OSB features cross-oriented wood strands, hence its name—oriented strand board. The rectangle-shaped wood strands are mixed with resin and layered in different directions for added strength, then pressed and heated to create large panels. The panels are then cut into different-sized boards. While OSB is a different product than plywood, it matches plywood’s strength values per thickness. For example, 7/16 OSB has the same span rating and strength factor as ½” CD four-ply.
Best lumber for OSB
There are many OSB mills across Canada and the U.S. In Canada, you’ll typically find OSB made from aspen trees, while southern yellow pine is more commonly used in the U.S. as it grows quickly. Historically, some builders preferred using the aspen boards as southern yellow pine boards were more prone to warping in certain environments. Today, this isn’t an issue anymore, as manufacturers have dialed in the strength and consistency of their OSB, regardless of what tree species they use.
Common uses for OSB
OSB panels can be used similarly to plywood and are commonly used for walls, flooring, and roofing. For roofing, the panels come embossed with a grid pattern on one side to add texture to the board, making it easier for roofers to use and walk on when working in slippery conditions. Unlike plywood, one of OSB’s primary industrial uses is as siding for large vans and trucks, thanks to fiberglass-reinforced jumbo panels (such as 12’ x 24’). It’s not possible to make these types of panels with plywood, but jumbo OSB panels are able to be manufactured while also being cost-effective.
Price difference between plywood and OSB
OSB and plywood pricing has changed significantly in the past four to five years. Previously, from the late nineties to late-2010s, plywood continued to be slightly more expensive than OSB. Between the COVID-19 pandemic, increasing lumber rates, and higher demand for OSB, OSB’s market share has grown—and so has its market price. In recent years, OSB has regularly been more expensive than plywood.
So, is OSB or plywood best for your work? Learn more by checking out other recent episodes in our Plywood Series, see how to choose a plywood panel, or learn about another useful manufactured wood product, ApplePly®.