Both birch and oak plywood are two of the most common types of plywood and are readily available at different retailers. When choosing between the two, you'll have more choices to make than just which looks better for your project. Plywood is often a confusing purchase if you're unsure -- especially due to the many factors that play into the different types of available plywood.
How Plywood is Made
Veneer core is the most common core for plywood and consists of several veneer layers -- each 2 mm to 6.5 mm thick -- laid perpendicularly and then finished with a veneer layer on each face. The perpendicular layers provide more stability; the more layers the board has, the more stable it will be. The cross-banded layers also prevent the plywood from shrinking, warping or swelling like solid wood. The strength and stability of the plywood also depends on the species used as the veneer core.
Top-Layer Veneer Choices
In both birch and oak plywood, you have several choices as to how the face veneer is applied. Rotary-cut veneers cover the entire sheet of plywood. Flat-sliced veneers, on the other hand, have several pieces glued side-by-side on the face of the plywood so that it resembles several boards. With flat-sliced veneer, there is the option of either slip-matched -- where the pieces are butted together -- or book-matched -- where the pieces are applied to the face of the plywood as mirror images, or they resemble the left and right side of an open book. Rotary-cut costs less than flat-sliced.
Veneer-core plywood using birch results in a harder, more stable product than pieces of plywood using fir, poplar or other hardwood veneer cores. This makes them somewhat of a specialty item, although they are not uncommon. Because birch is so hard, it's often used in applications where the edge will be exposed. Lumber-core plywood, on the other hand, is often the most expensive type of plywood and consists of several thicker strips of hardwood glued into a large panel. Lumber-core is often the best choice when you'll have exposed routed edges. MDF-core and particle-board core are both excellent choices when needed because the tiny particles used to create the core create a smooth, flat, evenly distributed surface.
Both birch and oak plywood are used for interior uses throughout the home, such as cabinets and furniture. When choosing between the two, the outer veneer -- or face veneer -- is what you will see in your finished project, unless the edges will be visible. The main concern of the project is the core of the plywood. Veneer-core, lumber-core or MDF-core plywood all have different uses and strengths.