You may think of plywood and OSB or oriented strand board, as one and the same when it comes to woodworking and construction, but they’re actually two different materials that have different strengths, weaknesses, and recommended uses. Here, we disclose the similarities and differences between these building materials.
The Similarities Between the Two
OSB and plywood have many things in common. First, their structural characteristics are almost equal, and the materials can pretty much be used interchangeably. They both stand up similarly to exposure to the elements such as harsh weather, and they both have similar equivalent nail withdrawal resistance. Additionally, these materials are installed in the same way using the same construction methods.
All About OSB
Over the past several years, OSB has become the most used sheathing and subflooring material, surpassing plywood in that category. One of the reasons for this is because OSB is cheaper than plywood—around $3 less per sheet—which makes quite a difference when it comes to a large-scale project.
The Advantages of OSB
Besides a lower price than plywood, OSB has other benefits as well. First, this material can be derived from small and fast-growing trees. Much of this material comes from tree farms rather than from forests, making it a more environmentally sound option. Another plus of this material is that it can be purchased in 9-foot sheets, meaning that it’s possible to sheath a wall from top to bottom with a single vertical sheet. OSB panels can also be made in lengths of up to 16 feet. Alternatively, plywood is limited to eight to 10 feet.
An additional advantage of OSB besides size availability and price point it that OSB has a more consistent density than plywood. Typically, OSB is made from as many as 50 strand layers packed and compressed into a thickness of five to seven piles.
The Disadvantages of OSB
To counter the advantages, there are also some disadvantages associated with OSB. First, this material is heavier than plywood. It’s about two pounds heavier per sheet, which is a significant load when you’re lugging an abundance of material.
Another downside of this material is that it's sometimes looked at as an inferior product by homeowners, simply because it's more affordable and looks different than plywood. Some then jump to the conclusion that it's a lower quality product.
All About Plywood
Historically, plywood has been the most popular material for building inside of a home even though OSB has become more prevalent, especially in recent years. Plywood is versatile, highly durable, and stable. It has a high impact and high chemical resistance.
The Advantages of Plywood
Plywood has a great reputation and is well-trusted with a solid performance track record. This wood is also available in a range of appearances, allowing the material to fit the wants and needs of any project demands.
Plywood is also very strong and stiff, meaning that it’s extremely durable. This sets the material apart from OSB, as the bending stiffness of plywood is 10 percent greater than OSB at equal joist spacing.
Perhaps one of the most notable advantages is that plywood has great moisture resistance. It also boasts quick drying times, surpassing those of OSB. Finally, plywood makes the perfect underlayment, acting as a great subfloor because you don’t need to worry about swollen edges that will loosen or weaken the tiles atop the wood.
The Disadvantages of Plywood
We’ve briefly touched on these cons, but the first one is that plywood is a bit more expensive than OSB. Additionally, this material does not come in sizes as large as those that OSB is available in, making it a little more difficult to use when boards of larger magnitude would simplify the project.
While both of these materials have different advantages and disadvantages, they're definitely beneficial in their own ways. These discrepancies should be considered as you plan your next DIY project. Finding the perfect materials is one of the most important steps on the path to success in the world of home improvement!