Understanding Wood Size at the Big Box Store
Nominal vs Actual Wood Sizes: What You Need to Know
I remember back to my early days of woodworking and not understanding this concept. I would draw up some plans, based on the lumber sizes that boards are called by, like a 1”x6”, head to the store, by my lumber and be upset when my plans were not right. Frustrating because of my ignorance. Read on to learn a bit more about this concept.
Nominal Sizes
The term "nominal size" is the rough dimensions of lumber at the lumber yard. For instance, a board labeled as "2x4" actually measures 2 inches by 4 inches when you buy it, right? Nope! In reality, this nominal size refers to the dimensions before the wood is dried and planed.
For instance, a true 2x4 actually measures about 1.5 inches by 3.5 inches. This reduction occurs because the lumber is planed down to create a smooth surface, and drying causes the wood to shrink slightly.
Actual Sizes
The "actual size" is the true dimensions of the lumber after it has been processed. Understanding actual sizes is critical for ensuring proper fit in your projects and a more accurate cut list.
Examples (This site has an excellent chart detailing the sizes Click Here)
1x common lumber: Nominal size 1” x 4” = Actual size 0.75” x 3.5”
2x common lumber: Nominal size 2” x 4” = Actual size 1.5” x 3.5”
4x common lumber: Nominal size 4” x 4” = Actual size 3.5” x 3.5”
Why Does It Matter?
Knowing the difference between nominal and actual sizes can save you time, money, and a good bit of frustration. Here’s why it’s essential:
Accurate Plans
Material Efficiency
Fit and Finish
Conclusion
Navigating the world of wood can sometimes feel daunting, but understanding nominal vs actual sizes will empower you on your woodworking journey. So, the next time you’re at your local lumberyard, remember that a 2x4 isn’t quite what you think it is! Embrace the weirdness of woodworking and let your creativity shine. Happy sawdust making!