Measuring Raw Lumber

Measuring raw lumber isn't too complicated, but it has a few of its own terms. I figure if I just talk about it briefly then I can go ahead and use the lingo freely in subsequent posts.

Explanation after the jump:


The picture above is a piece of walnut that is two inches thick. However, we wouldn't say it's two inches thick at this point. That is a piece of 8/4 (eight-quarter) lumber. You convert the thickness into the number of quarter inches it is, e.g. a two inch thick board is 8/4, and a one inch thick board is 4/4.

Commonly, when you buy raw lumber from the lumberyard, it comes unplaned, and has surfaces that look rough like in the picture above. You pay for it, in part, based on its thickness.

Most lumber I use starts its life as 4/4, and then I plane it down to 3/4", cleaning up the faces. You can buy 4/4, 5/4, 6/4, 8/4. Depending on what you need the wood for will determine what you buy.

Interestingly enough in international raw lumber measuring conventions (like when buying exotic lumber like mahogany or teak), 4/4 rough lumber is actually 9/8" thick. This is nice from the perspective that you have an extra 1/8" to play with and can eek out a slightly thicker table surface from 4/4 than you normally could.