OSB vs Plywood: Difference and Comparison

What is the difference between oriented strand board (OSB) vs plywood and which of these materials is a better choice?

Oriented strand board (OSB) and plywood are similar materials that can used interchangeably. These materials are panel products that are made similarly- OSB and plywood are made by compressing and glueing pieces of wood.

OSB and plywood are suitable materials to use for packaging and in construction. However, how these materials are manufactured contributes to their unique strengths and weaknesses.

So it’s important to understand the difference between OSB and plywood as it helps in making the right decision on which material to use.

Oriented Strand Board (OSB)

OSB is a reliable engineered wood material manufactured by adding adhesive and compressing several layers of wood strands in different orientations.

Oriented strand board (OSB) was invented in 1963 by Armin Elmendorf. OSB is a similar engineered wood material to plywood but there is a difference. The material is made of wood shavings tightly compressed with glue or resin under high heat and pressure.

Oriented strand board is a material with a rough and variegated surface. The material is produced in different types and thicknesses.

OSB is often confused with chipboard. But it’s a material that can be made from small trees grown specifically to make this type of engineered wood material.

OSB is a suitable engineered wood with mechanical properties and this makes it the perfect construction material. Oriented strand board has become the preferred material- it has become more popular than plywood, and it currently commands 66% of the North American structural panel market.

OSB is a reliable material mostly used in flooring, sheathing in walls, and roof decking. A quantity of OSB is also used to make furniture.

Also Read: Stain vs Varnish: Difference and Comparison

Plywood

Plywood is an engineered wood made by cross-laminating layers of wood veneer glued together with adjacent layers. Plywood is an engineered wood that originated from the family of manufactured boards, which also include oriented strand board (OSB), and other materials such as particle board and medium-density fireboard (MDF).

To manufacture plywood, a process called cross-graining is used to increase the material’s strength. Piles of wood veneer are glued together with adjacent layers, with their wood grain rotated about 90 degrees to one another.

Plywood usually comes in a variety of types and grades. There is a grade A, B, C, D, and even BC or CD.

Grade A: This is the highest grade of plywood which is also called cabinet grade. It’s a smooth wood material, with all voids filled and no knots.
Grade B: This is the second highest grade of plywood that is also sanded smooth, and may have up to one-inch defect.
Grade C: This is usually unsanded and has more defects.
Grade D: This grade has a rougher surface than the previous grade. They have larger defects and are commonly used for plywood subfloors or under asphalt roof shingles.

Other grades also available are BC or CD. The “BC” and “CD” classifications indicate that one side has a higher grade compared to the other.

OSB vs Plywood: Key Differences between OSB and Plywood

Oriented strand board (OSB) and plywood may be engineered woods from the family of manufactured boards, but their manufacturing process is quite different.

Let’s look at what differentiates these engineered materials.

OSB vs Plywood: Strength

Oriented strand boards and plywood share a similar quality in terms of their strength. However, plywood is stiffer than OSB by approximately 10%.

Despite this little difference, both materials are reliable to use in packaging and construction. But if you are looking for a material capable of holding nails and screws for a longer period, then plywood is your best option.

Also Read: Stain vs Paint: Difference and Comparison

OSB vs Plywood: Moisture Resistance

Plywood is also the better option and resists moisture.

Oriented strand board (OSB) is an engineered wood that usually takes a longer period to become saturated when wet. It also takes a longer period to dry.

OSB becomes swollen when it comes in contact with water. The material gets swollen when it absorbs water because the compaction stress is released as a result of the wood chips being pressed into panels.

OSB vs Plywood: Weight

Another factor to consider between these two engineered woods is how much the finished products weigh.

Oriented strand board weighs more than plywood due to their manufacturing process.

On average, a 23/32-inch 4×8 foot plywood piece weighs approximately 67 pounds (30.3 kilograms), whereas a piece of oriented strand board of the same size weighs about 78 pounds (35.3 kilograms).

This is a major difference to consider, especially if one of these materials is to be used for a roofing project.

OSB vs Plywood: Environmental Friendliness

Oriented strand board (OSB) is a building material considered to be less harmful to the environment. It’s a “green” building material as it’s made of wood chips from an entire tree.

While plywood requires larger-diameter trees usually harvested from old-growth forests, OSB is made from smaller-diameter trees.

Also Read: Stain vs Paint Deck: Difference and Comparison

Cost

Which of these engineered woods is more expensive to purchase for a project?

Well, if you are on a budget, then OSB is the material for you. OSB is more affordable than plywood. A 4×8 sheet of OSB will cost about $6, while the same size of plywood will cost about $10.

OSB vs Plywood: Comparison Chart

	Oriented strand board (OSB)	Plywood
Material composition	Wood strands and adhesives	Thin wood veneers glued together
Moisture resistance	Less resistance and can swell	Has a better resistance and dries faster
Strength	Uniform strength across the board	High strength, especially along the edges
Application	Sheathing, subflooring, and roofing	Furniture, construction, and subflooring
Cost	Less expensive	More expensive

Also Read: Blueprint vs Schematic: Difference and Comparison

OSB vs Plywood: OSB Pros and Cons

Pros	Cons
Can be used to manufacture larger panels than plywood	Oriented strand board (OSB) is not water resistant and cannot be used for exterior projects
Less expensive material compared to plywood	Weighs more than plywood
Considered a more environmentally friendly product as it can be made from scraps of smaller trees	Doesn’t hold screws, nails, and fasteners as firmly as plywood
Does not delaminate as plywood	Swells more than plywood when they come in contact with moisture

Plywood Pros and Cons

Pros	Cons
Nails, screws and fasteners are likely to remain in place for a longer period	Cost more than OSB
Weigh less than OSB	Can delaminate or separate with humidity or extreme heat.
Plywood panels swell less than OSB when they come in contact with moisture	Used wood veneer sheets that make it less environmentally friendly
Plywood off-gasses are less harmful gases than OSB	Can sometimes have gaps or voids between the plys

OSB vs Plywood: What’s the Best Choice?

From what we have discussed so far in this guide, choosing one material over the other depends on a few factors.

Plywood would be a better option for an exterior project and it weighs less than an OSB.

However, if you are more concerned about using a material that is environmentally friendly and less expensive, OSB is the best choice for your project. OSB and plywood are similar in terms of strength and they are also reliable to use for roof decking.

Conclusion

OSB and plywood are engineered wood from the family of manufactured boards. Their manufacturing processes are different but they serve unique purposes in packaging and construction.

Recommendations

References

Wikipedia: Oriented strand board
- Plywood
International Association of Certified Home Inspectors: OSB vs. Plywood

OSB vs Plywood: Difference and Comparison

Oriented Strand Board (OSB)

Plywood