Structural Lumber Explained

Last time we mentioned the term "2x" (pronounced "two by"). Since some people unfamiliar with the industry might not know what this means, and we'll be using this term frequently, let's quickly explain the commonly used types of structural lumber.
1️⃣ Sawn lumber: Derived from the word "saw," this refers to lumber directly sawn from tree trunks. In the US, it comes in standardized sizes, such as 2x4, 4x4, 4x12, etc., with units in inches. ⚠️ This is a nominal size, and the actual size is usually slightly smaller. Figure 2 shows some conversion examples; the double quotes indicate inches. The 2x lumber often mentioned is the lumber shown on the right in Figure 2.
2️⃣ Glulam (Glued Laminated Timber): By stacking and gluing 2x lumber horizontally, larger timbers can be created, solving the problem of insufficient tree trunk size or excessive waste.
3️⃣ LVL, PSL, LSL: These are types of engineered wood products made from processed raw materials. They can replace sawn lumber, generally offering higher strength but also higher cost.
4️⃣ Plywood: Common thicknesses are 1/2 inch, 3/4 inch, or 1 inch. This is a common structural sheathing material used on walls, floors, or roofs.  The typical size is 4 feet wide by 8 feet long. ⚠️ This component will be frequently mentioned in future explanations.
5️⃣ OSB: An alternative to plywood.