Plywood used for roofing is a structural base layer called roof decking or sheathing. The most common type is exterior-grade plywood, which is 1/2 inch to 5/8 inch thick. This plywood sits on top of the roof trusses and holds up shingles, tiles, or metal panels. It must be strong and water-resistant because it bears the weight of your roofing materials and protects your home from rain and snow.
What Grade of Plywood Do Roofers Use?
Roofers use exterior-grade plywood because it can handle wet weather and temperature changes. This type has waterproof glue between its layers, so it won’t fall apart when it gets wet. Interior plywood fails quickly on roofs.
The thickness matters too. Most residential roofs use 1/2 inch or 5/8 inch plywood. Thicker plywood is stronger but costs more. According to RubyHome, roof installation costs range from $4 to $40 per square foot, and the plywood is a key part of that cost. For a 1,700 square foot roof, total costs can run from $6,800 to $68,000 depending on materials and labor.
Related articles:
- What Wood Is Used for Roofing
- What Are the 3 Types of Shingles Used When Roofing
- What Plywood for Roofing
- What Wood Is Used for Roofing Beams
- Which Plywood Is Used for Roofing
- Can You Put Metal Roofing Directly on Plywood
- How to Install Metal Roofing Over Plywood
- What Size Osb Is Used for Roofing
- What Plywood Do You Use for Roofing
Why Plywood Is Your Roof Base
Plywood creates a solid foundation for everything above it. Shingles, tiles, and metal panels all nail into the plywood. Without good plywood, your roofing materials will sag or fail early.
Quality plywood also affects how long your roof lasts. According to industry data, asphalt shingles last 20 to 30 years on average, but poor plywood can cause leaks much sooner. Metal roofs can last 40 to 80 years, but only if the base is solid. Concrete and clay tiles last 100 years or more, but again, the plywood underneath must be strong and dry.
Common Plywood Types for Roofs
| Plywood Type | Thickness | Best Use |
|---|---|---|
| Exterior Grade | 1/2″ to 5/8″ | Standard residential roofs |
| CDX Grade | 1/2″ to 5/8″ | Budget-friendly option |
| Tongue and Groove | 5/8″ to 3/4″ | Cathedral ceilings and attics |
Do You Need to Replace Plywood During a Roof Replacement?
Not always. If your plywood is dry and solid, you can reuse it. But if it has rot, mold, or water damage, it must be replaced.
br>
According to RubyHome, the average roof replacement cost is $9,526, with a range from $5,868 to $13,217. New plywood can add to that cost if it needs replacing. Inspect your plywood carefully during replacement. Damaged plywood causes leaks and leads to costly repairs inside your home. The U.S. roofing market is valued at $81.3 billion as of 2025, according to IBISWorld, showing how critical roofing infrastructure is to American homes. Roofers check plywood condition before installing new shingles or materials to ensure your roof will last its full lifespan.
Related articles:
- Can Osb Be Used for Roofing
- What Type of Plywood Is Used for Roofing
- How Thick Is Roofing Plywood
- What Plywood to Use for Roofing
- Can a Roofing Nailer Be Used for Siding
- What Thickness of Plywood Is Used for Roofing
- What Are Roofing Nails Used for
- In What Part of Roofing Is Step Flashing Used
If you need help with your roof, reach out to a trusted roofing company for clear pricing and reliable service.