Plywood vs OSB: Which Sheathing Should Contractors Choose?

For walls, roofs, and floors, contractors in Ontario typically choose between plywood and OSB (Oriented Strand Board) for sheathing. Both are engineered wood products, but which is better for your project? Let’s break down the differences in cost, performance, and availability.

Plywood Sheathing

• Made by layering thin sheets of wood veneer with alternating grain.

• Strong, durable, and resistant to warping.

• Handles moisture exposure better than OSB.

• Typically costs more than OSB.

OSB Sheathing

• Made by compressing wood strands with adhesives.

• Uniform appearance and strength.

• Less expensive than plywood, making it popular for budget builds.

• More prone to swelling when exposed to water.

Key Differences

• Cost: OSB is 20–30% cheaper than plywood.

• Durability: Plywood is more moisture-resistant, especially for roofing and flooring.

• Weight: OSB panels are heavier, sometimes harder to handle.

• Building Code: Both are accepted by Ontario Building Code for sheathing applications.

Average Costs (Ontario 2025)

• Plywood (1/2", 4x8): $35–$50 per sheet.

• OSB (7/16", 4x8): $25–$35 per sheet.

Where Contractors Buy in the GTA
Confirmed Construction Materials (ConfirmedCM) supplies plywood and OSB sheathing with contractor pricing and delivery across Markham and the GTA.