In the last 20 years, an increasingly popular building material option in the U.S. is “oriented strand board,” better known as OSB. But even though it’s now common to find it in a home’s materials list, many people are unaware of its exact benefits. Here are the details on what makes OSB a good option for many building projects.
What Is OSB?
OSB was invented in the 1960s, but became popular in the U.S. only in the last two decades. It's now known as a way to use wood material (sometimes called “wood scrap”) in a new and better way than its earlier incarnation as wafer board. The wood material is formed into wood strands that, instead of being pressed together in random ways, are laid out in similar directions — hence the name “oriented strand.”
This specific composition creates a strong, long-lasting product that can outperform other wood sheets, including plywood, due to the properties described below. OSB is made in many standard sizes (often 4’x8’ sheets of varying thicknesses), but also can be manufactured to order for a custom project. This article focuses on stock items, many of which are available at your local McCoy's.
Types of OSB and Their Uses
In addition to different sizes, OSB also comes in different formats for specific uses. Here are a few of the various types, and where you might use them:
- Radiant Barrier OSB: Radiant barrier is created with a foil layer on one side. This is often used in attic construction, as the foil layer helps keep the attic cooler in the summer (by as much as 30°F!), and can ease the work of a home’s HVAC system.
- Flameblock OSB combines flame-spread and burn-through resistance to meet fire codes. Its energy efficiency benefits are similar to radiant barrier without the foil.
- Tongue-and-Groove OSB: The tongue-and-groove variety is used in flooring or roofing due to its strength, and its resistance against warping.
- Wall OSB: The wall type isn’t just great for sheathing home construction. Its built-in, weather-resistant outer layer can eliminate the need for house wrap in regions where wrap is not required by code. It won’t blow off or tear, and while it’s water and air resistant, it still allows for moisture to escape.
What’s the Difference Between OSB and Plywood?
While you might confuse OSB and plywood, they do have slightly different purposes. OSB is created from long strips of sustainable, fast-growing trees (such as aspens, southern yellow pine, or other hardwoods.) These strips are dried, oriented the same direction, and then compressed to form one sheet, with the help of resin and a small amount of wax.
OSB’s reliance on that small amount of wax also means it comes with more water-repelling features than plywood. And its resistance to warping, cupping, or bending— even in extreme temperatures — makes it ideal for use on a deck, attic, floors, or walls. It also makes it ideal for very hot climates, where other composite boards, like plywood, may delaminate.
This specific method of composition is one way OSB is different from plywood, and may appeal to those who are looking for a greener option for construction materials. OSB is made from smaller diameter, fast-growth trees that can be farmed instead of using old-growth timber.
While there is very little off-gassing from other materials that rely on formaldehyde-based binders, OSB can be made without them. Those building for anyone with environmental sensitivities could choose it over plywood, especially for interior home materials.
While OSB can be made with different formulations, it is known across the industry for being uniformly strong, hardwearing, smooth, and defect free. Typically, it is slightly cheaper than plywood making it a great option or budget-friendly option.
Why OSB Can Be Expensive
While OSB’s performance rating is top notch, nonetheless, it can also be costly when compared to materials created by inexpensive methods. What you’re paying for is the careful manufacturing process and the noted performance and uniformity of the product. And since new home building and renovations to existing homes have increased in the last year, so has the demand over the existing supply of construction materials.
Why Buy OSB from McCoy’s
We know you have options when it comes to where to buy your lumber, including OSB, but we know our McCoy’s regulars keep coming back for a reason. Our knowledgeable staff meet you with answers to all your questions, and we’ll help you get your project done, every step of the way.