What’s Full Dimension Lumber?

Why does our Barndominium wood look different from a house?

All your life, you have probably seen wood planks like 2x4s and 3x4s and wondered to yourself if those are really all measured that way. You would be right to wonder, because the truth of it is: It’s a lie! Wood that has numbers like 2x4s are really only 1.74×3.75, which isn’t nearly as catchy, is it?

Well, not a lie, exactly, so much as an interesting practice dating back hundreds of years! It all comes down to the difference between standard “Nominal Dimensional Lumber” and “Rough Sawn Full-Dimensional Lumber“.


Dimensional Lumber:

Before we go further, it’s important to know that “Dimensional Lumber” just means wood or lumber, that is cut and milled to specific dimensions. Like how wheels on a car have a set size, so every new Toyota Camry will use the same tires. It is a practice of standardization, though as we will see, this can be a little confusing!


Nominal Dimensional Lumber:

Nominal Dimensional Lumber, or simply Dimensional Lumber, is a highly processed and smooth kind of wood that has been dried in a factory. The wood’s “actual” size is based on the size that wood used to dry to from it’s original cut. Because wood is full of water, it shrinks when dried, meaning the cut wet wood and the dried wood we usually get can be different and size. The number we use on a day to day basis, like a 2×4, is used to categorize the wood and we call that “Nominal Dimensions”. It’s not a lie to say that they are a 2×4, because the term “2×4” is more of a name, than the dimensions. Nearly all the 2x4s at Lowe’s or Home Depot have roughly the same size, because they all follow the same practice.


Rough Sawn Full-Dimensional Lumber

Rough Sawn lumber is not smooth and pressed like the boards you see at a hardware store, they are much closer to the initial cut from a tree. This process involves a much simpler air drying method that preserves the size of the lumber. As a result? Big, rough planks that look like they came straight from the forest, and offer that wood cabin feel to any home or barn they are a part of. Because these plans are often locally sourced, and minimally processed, they can look beautiful, while helping to maintain the environment as well!

What We Use

Having covered what these sorts of woods are, you may wonder what we use, and where! The fact is, we use both types of lumber, and in all sorts of ways! Full Dimension Lumber is best used when you can see it, so we are careful to use it when a wall will just cover it up. Meanwhile, standard Nominal Lumber is smooth and simple to use, allowing our builders to form frames and studs quickly and easily. Here is a short list to help you understand where you can expect our woods:

  • Houses
    • Full Dimension: Accents when requested.
    • Nominal Dimension: Framing and Studs. Most wood will be these.
  • Barndominiums
    • Full Dimension: Major Horizontals, Verticals and other Visible posts
    • Nominal Dimension: Interior Wall Frames and studs.
  • Barns
    • Full Dimension: Most Woods used.
    • Nominal Dimension: Small Internal Walls for human rooms.

Keep in mind, each plan will be unique, and you can work with our designers and architects to find the best way to make your building pop!