In the woodworking world, quality and grade often get lumped together. Although they are related, they are not the same thing. In this blog, we dive into the differences between the two.
The grade determines the appearance of the board. Most hardwood lumber suppliers grade their lumber by the National Hardwood Lumber Association (NHLA) guidelines. These guidelines specify the size and location of defects on the board. The higher the grade, means fewer defects, which results in more usable material. Generally, hardwood lumber is sold in three different grade groupings; Select and Better, #1 Common, and #2A & #3A.
Select and Better is a group of the three highest grades; Firsts and Seconds (FAS), FAS One Face (F1F), and Selects. They are sold together for a couple of different reasons. The first is few Select and Better boards come from a log. So by grouping the three, the lumber can be accumulated faster and sold in volume. The second reason is selects, F1F, and FAS boards look relatively the same. They all require you to yield at least 83 1/3%. The most significant difference is select boards only have to be 4” wide x 6’ long while FAS and F1F have to be 6” wide x 8’ long. Select and Better boards are used for products that require clear cuts of length or width. Select and Better is most often used by woodworkers, furniture makers, window and door manufacturers, and moulding and millwork manufacturers.
The next grade is #1 Common. #1 Common is sold as a standalone grade. It has a yield of 66 2/3%, and the boards are only required to be 3” wide x 4’ long. Some companies will often buy both Select and Better and #1 Common. By doing this, they get their long and/or wide pieces from the Select and Better and use #1 Common for the narrower and/or shorter pieces. Cabinet shops often use #1 Common for shorter pieces of the face frame, window, and door manufactures and by some flooring manufactures.
#2A & #3A is the last group of grades that we are going to touch on. This group is a combination of #2A Common and #3A Common. Boards in this grade group have a yield of 33 1/3% – 50% with the minimum size board being 3” wide x 4’ long. #2A & #3A is almost exclusively sold to flooring manufacturers. Most hardwood flooring is narrow in width and short in length, which makes this grade ideal to use.
Many times, someone may look at a low-grade board and say that it has low quality, but this isn’t necessarily the case. Lumber can have a ton of internal stresses. So in the lumber business, quality isn’t determined by appearance (that what we have a grade for), but rather, how the lumber reacts once you start machining it.
I’m sure many of us have looked at a 2×4 from a big box store and noticed that it had a huge bow or twist. That bow or twist is most likely caused by internal stresses. A similar thing could happen once you start machining the lumber if it wasn’t properly conditioned during the drying process. If you cut a strip of wood 2” wide, you want that piece to stay nice and flat. The last thing you want is for the piece to bow and twist. This is where quality comes into play. Boards that have been conditioned and dried properly should stay flat and straight before AND after the lumber has been machine. This is what is considered to be of high quality in the lumber industry.
Related But Not the Same
Once you start diving deeper into quality and grade, you’ll start noticing some areas where they overlap. Grade accounts for some twist, bow, and side bend. You’ll also find that things like knots and other defects can affect the quality of the lumber. These few areas make quality and grade relate, but they still have their differences. The best rule of thumb to follow is appearance affects grade, and internal stresses affect quality.
The last question you might be asking yourself is how to find both high grade and high quality. Check out our blog, “Dangers of Buying Low Quality Lumber (And How it Costs You).”