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When you’re looking for lumber near you, you need to make sure you’re getting the right building supplies for your project. The things you’ll need to consider vary from item to item. Take plywood, for example. The grade is very important. In fact, to say it’s critical may be an understatement. Here at your local building supply, Sherwood Lumber takes pride in providing top-notch customer service so you’ll get everything you need. Here’s what you need to know about the different grades of plywood.

Plywood Classification

Before we talk about the different grades of plywood, we must first talk about how plywood is classified at lumber yards and building supply stores. Plywood falls into one of four categories: exterior, exposure 1, exposure 2, or interior. But what do these labels mean?

  • Exterior plywood has a full waterproof bond/glue in between its layers and is best suited for projects that will be constantly exposed to moisture and weather.
  • Exposure 1 plywood has a waterproof bond as well, but this glue isn’t permanent like exterior lumber. This means exposure 1 plywood is ideal for temporary exposure to the elements.
  • Exposure 2 plywood has a medium-strength glue and is best used on construction projects that rarely come in contact with moisture.
  • Interior plywood, as its name suggests, means that the plywood should only be used for indoor use.

Plywood grading system A-D

Now that you have a good idea of how plywood is classified, here’s how it’s graded.

  • – This plywood is very smooth and tends to be the most expensive. In some instances, knots in Grade A plywood can be patched, but there must be less than 18 knots. This is the perfect lumber for cabinetry.
  • – Grade B plywood has a durable and solid surface with very minimal amounts of splitting tolerated.
  • C – Knots, knotholes, discoloration, sanding defects, and other small impairments are acceptable for Grade C plywood.
  • D – The least expensive of the grades, Grade D plywood allows large knots and knotholes to remain.