OSB vs. Plywood: Which Is Better?

As a builder and flooring installer, I’ve learned the benefits of oriented strand board (OSB) and have often used it as a cost-effective alternative to plywood for sheathing and subfloors. The material works well in many situations and applications, but I can tell you one instance in which I’m convinced OSB doesn’t work: as interior wall paneling.

The previous owner of a home I flipped in Colorado thought the chaotic appearance of OSB worked as a feature in the living room. To my eye, however, it made the room look and feel like a workshop. But not everyone would agree!

“It really depends on the specifics of your project and what matters most to you,” says interior designer Elizabeth Vergara when asked if OSB looks good in a home setting. “I mainly work with luxury apartments and residential homes. Most of my clients are open to splurging on premium quality items to achieve a luxury aesthetic.”

OSB wall paneling, in other words, does not equal luxury. On that score, I couldn’t agree more. The real value of OSB is in its structural integrity. Building codes, the Engineered Wood Association, architects and most builders rate plywood and OBS sheathing as equal in strength and durability. There’s no doubt that plywood, with its smooth face, looks better than OSB. Looks aren’t everything, though.

About the Expert

• Elizabeth Vergara has been helping homeowners design and renovate their upscale homes for over 13 years. After starting a professional career with a prestigious construction and architecture firm in New York City, she started her design-and-build company, Vergara Homes.

OSB vs. Plywood Characteristics

What Is OSB?

Oriented Strand Board (OSB) is a structural, engineered wood panel now used for about 70 percent of all floor, wall and roof sheathing in North America. It’s available in 4-foot wide sheets that are eight to 16 feet long and with thicknesses that vary from 1/4 in. (6.5 mm) to 1 1/8 in. (28.5 mm).

How Is OSB Made?

Manufacturers produce OSB by tightly pressing together rectangular wood strands in crisscross patterns and combining them with glue or resin under high heat. According to the Engineered Wood Association (known by the acronym APA, since it used to be called the American Plywood Association), the manufacturing process produces “a solid panel product of consistent quality with no laps, gaps, or voids.”

What Is OSB Used For?

OSB is primarily a structural material; builders mainly use it for wall and roof sheathing and subfloors. It also has several utility uses, including trailer liners and flooring for recreational vehicles. Some people even use it to make furniture, cabinets and even wall paneling.

How Much Does OSB Cost?

OSB is generally cheaper than plywood. Depending on thickness, a 4 X 8 sheet costs between $15 and $43.

Building With OSB

Should I Run OSB Horizontally or Vertically?

When installing OSB on a subfloor, the strength axis (the longer edge) should run perpendicular to the supporting framing. Vertical or horizontal is acceptable when installing it as sheathing unless a designer or engineer specifies a certain direction.

Which Side of OSB Should Face Up?

OSB has a rough, unfinished side and a smooth side with a thin, moisture-resistant finish. When installing on a roof or subfloor, the rough side should be facing up to provide traction for walking. When installed on walls, the smooth side should face the studs and the rough side should face out. Sheets are usually marked on one side with a stamp that says “This Side Down.”

Pros and Cons of OSB

Pros

Most builders rate plywood and OBS equal in strength and durability, but OSB does have some advantages over plywood:

• It has a textured, slip-resistant surface, which makes it safer to install on roofs.
• It often comes with pre-scribed lines at 16- and 24-inch intervals, which makes it easy to locate underlying studs and rafters for nailing.
• Unlike plywood, which may have overlapping knots that undermine its strength, OSB is free of laps, gaps and voids.
• OSB is available in longer sheets, which minimizes the number of joints that can leak.
• OSB is manufactured from small, fast-growing trees, which makes it a sustainable forest product.

Cons

• Besides appearance, the main disadvantage of OSB is that the edges tend to swell when they get wet and remain swollen even after drying out. This results in ridges that can “telegraph” through shingles and even carpets when you use OSB as a subfloor.
• OSB tends to be heavier than plywood. A 4X8 sheet of 3/4-inch sheet of OSB weighs 78 pounds while a comparable sheet of plywood weighs only 67 pounds.

What Is Plywood?

Plywood is another type of structural engineered wood panel. It comes in four-by-eight-, nine- and 10-foot sheets that range in thickness from 1/8 in. (3.2 mm) to 1 1/4 in (31.75 mm). It’s available in many appearance grades, “ranging from smooth, natural surfaces suitable for finish work to more economical grades used for sheathing,” according to the APA.

How Is Plywood Made?

The APA explains that plywood is “manufactured from thin sheets of cross-laminated veneer and bonded under heat and pressure with strong adhesives.” The inner sheets are typically obtained from softwoods such as fir and pine. The face sheets may be softwood or a more decorative hardwood species.

What Is Plywood Used For?

Because of its smooth surface, plywood has decorative and structural value. As Vergara puts it: “If you’re into the look of things, plywood tends to win on the aesthetics front with its smoother surface.” Lower grades of plywood are suitable for sheathing, subfloor and other construction purposes, while higher grades are used for cabinetry, wall paneling and other interior design applications.

How Much Does Plywood Cost?

A sheet of plywood will set you back more than a comparable sheet of OSB, but the actual cost is highly dependent on grade, which ranges from A (cabinet grade) to D (utility grade). Plywood prices range from $4.50 to $10 per square foot.

Why is plywood more expensive than OSB?

Plywood is manufactured according to more exacting standards than OSB, and the raw materials are generally sourced from high-quality logs. On the other hand, the wood chips used to make OSB come from smaller-diameter, faster-growing trees, and some may come from recycled materials.

Pros and Cons of Plywood

Pros

• Because it comes in decorative as well as utility grades, plywood has more uses than OSB. Higher grades can be stained and finished just like wood.
• The smooth face of plywood makes a better subfloor surface for laying tiles.
• Plywood tends to be about 10 percent stiffer than OSB and is better at holding nails.

Cons

• Plywood can delaminate when exposed to moisture for a prolonged period.
• When left in the rain, unused plywood sheets can warp.

OSB vs. Plywood: Which Is Better?

The main reason for choosing OSB is the cost. Its lower price can generate big savings in a large construction project. For example, as sheathing and subfloor materials, plywood and OSB are essentially equivalent, but the lower cost of OSB makes it more cost-effective in those areas.

When it comes to cabinetry, furniture and other designer uses, the smooth face of plywood is the preferred material.

FAQ

Can you mix OSB and plywood?

Mixing OSB and plywood in the same application generally isn’t recommended. Sheet thicknesses aren’t always the same, making it difficult to match edges and get leak-proof seams.

OSB vs. Plywood: Which is more water-resistant?

Plywood absorbs moisture faster than OSB, but it also dries out more quickly, and it isn’t prone to edge swelling.

OSB vs. Plywood: Which warps more?

Because it’s manufactured from full sheets of veneer, plywood tends to warp more than OSB, but this tendency decreases with the increasing number of alternating layers.

Sources

• APA – Engineered Wood Association: Oriented Strand Board (OSB)
• APA – Engineered Wood Association: Plywood