Types of Plywood Grades

Plywood is an essential material in construction and woodworking. Knowing the types of plywood grades is key when selecting the right material for your project.

Whether you’re building furniture or working on a DIY project, choosing the correct grade of plywood ensures durability, appearance, and cost-effectiveness. Let’s explore the types of plywood grades and understand how to use them effectively.

What Are Plywood Grades?

Plywood grades are a classification system that helps distinguish the quality of plywood sheets. Each sheet is graded based on its appearance, quality, and suitability for different applications.

The types of plywood grades range from A to D, with A being the highest quality and D being the lowest. These grades refer to the condition of the veneer on the face and back of the plywood, indicating the level of defects, smoothness, and finishing.

Why Understanding Plywood Grades Is Important

Understanding the types of plywood grades is crucial because the grade determines the strength, durability, and aesthetic appeal of the plywood. High-quality grades like A and B are ideal for projects that require smooth surfaces, like cabinets or furniture, while lower grades are more suited for construction work or areas where appearance is less important.

Types of Plywood Grades

Types of plywood grades range from A to D, with A being the highest quality. Each grade is suited for different projects based on appearance and structural needs.

1. Grade A Plywood

Grade A is the highest quality plywood grade. This grade is known for its smooth surface, free from major imperfections. The veneer used in Grade A plywood is carefully selected, minimizing knots and splits. It’s sanded, and the surface is often ready for staining, painting, or varnishing. 

Best Uses:

  • Furniture
  • Cabinets
  • Decorative wall panels

2. Grade B Plywood

Grade B plywood is of slightly lower quality than Grade A. It may have some imperfections, such as minor knots or splits, but they are usually filled with putty. This grade is also sanded and can be used for visible projects, though some minor finishing may be required.

Best Uses:

  • Furniture construction
  • Shelving
  • Flooring underlayment

3. Grade C Plywood

Grade C plywood contains more noticeable imperfections. You may find larger knots (up to 1.5 inches in diameter) and splits, but these do not typically affect the plywood’s structural integrity. This grade is often used in areas where the plywood won’t be visible, or it can be covered with another material.

Best Uses:

  • Subflooring
  • Sheathing
  • Areas where appearance is not a concern

4. Grade D Plywood

Grade D is the lowest plywood grade. It has visible knots, splits, and other defects. The surface is rough, and these imperfections are not filled or sanded. This grade is suitable for construction projects where appearance isn’t a priority but structural strength is still required.

Best Uses:

  • Roofing
  • Wall sheathing
  • Flooring

Plywood Veneer Types and Grades

In addition to the general types of plywood grades, plywood is also categorized based on the veneer grade. Veneers are thin layers of wood that are glued together to form the plywood. Veneer grades follow the same A-D grading system, but the veneer’s front and back faces may have different grades.

Front Face Veneer

  • A-grade veneer: Smooth, free from defects.
  • B-grade veneer: Minor defects filled with putty.
  • C-grade veneer: Larger knots and visible flaws.
  • D-grade veneer: Unfilled holes and noticeable imperfections.

Back Face Veneer

The back face of plywood is often of a lower grade, as it won’t be seen. Commonly, the back face may be a grade or two lower than the front.

Types of Plywood Based on Core Composition

While types of plywood grades focus on surface quality, plywood can also be classified based on its core composition, which affects strength, weight, and suitability for different uses.

1. Softwood Plywood

Made from softwoods like pine, cedar, or fir, this plywood is commonly used in construction and structural applications. Softwood plywood typically has lower-grade surfaces and is ideal for subfloors, roof decking, and wall sheathing.

2. Hardwood Plywood

Hardwood plywood is made from hardwood trees like oak, maple, and birch. This plywood is often used for furniture and cabinetry due to its durability and attractive grain patterns. It’s usually graded higher because of its smoother surface.

3. Tropical Plywood

Made from mixed tropical woods, tropical plywood is known for its strength and resistance to moisture. It’s often used in marine applications and exterior projects.

4. Birch Plywood

Birch plywood is highly durable, making it perfect for furniture, cabinetry, and other decorative uses. It often has an A or B-grade veneer, which is smooth and visually appealing.

Selecting the Right Plywood Grade for Your Project

When choosing between different types of plywood grades, consider these factors:

  • Appearance: If the plywood will be visible, opt for A or B grades.
  • Cost: Higher grades like A are more expensive, but they save time and effort on finishing.
  • Strength: Lower grades like C and D are suitable for structural purposes where appearance doesn’t matter.
  • Application: Indoor projects benefit from higher grades, while outdoor projects can use lower grades if hidden behind siding or roofing.

Plywood Thickness and Sizing

While grades are critical, plywood also comes in a variety of thicknesses, typically ranging from 1/4 inch to 3/4 inch. Thicker plywood is stronger and more durable, making it suitable for floors and walls, while thinner plywood is often used for smaller projects.

  • 1/4 inch: Suitable for lightweight projects, such as drawer bottoms.
  • 1/2 inch: Often used for furniture and cabinets.
  • 3/4 inch: Ideal for structural applications like subfloors and walls.

How to Identify Plywood Grades

Each sheet of plywood comes with a grade stamp that indicates the quality of the face and back veneers. For example, a sheet might be labeled “A-C,” meaning one side is Grade A, and the other side is Grade C. Understanding this labeling will help you choose the right plywood for your project.

Conclusion

Knowing the types of plywood grades is essential for ensuring the success of your woodworking or construction project. From the high-quality, smooth surface of Grade A to the rough imperfections of Grade D, each grade has specific uses and benefits.

Whether you’re building furniture or framing a house, selecting the right plywood grade ensures your project meets your standards for durability, appearance, and cost.

What Is The Best Plywood Grade For Furniture?

Grade A plywood is the best choice for furniture due to its smooth surface and minimal imperfections.

Can I Use Grade “D” Plywood For Outdoor Projects?

Yes, Grade D plywood can be used in outdoor projects, especially where appearance is not a concern, such as under roofing.

What Does “A-C” Mean On Plywood

The “A-C” label means one side of the plywood is Grade A, while the other side is Grade C. This type of plywood is often used when only one side will be visible.

Is Plywood Thickness Important?

Yes, plywood thickness affects its strength and durability. Thicker plywood is better for floors and walls, while thinner plywood is suitable for lightweight projects.

What Grade Plywood Is Best For Cabinets?

Grade A or B plywood is ideal for cabinets because of its smooth finish and appearance.