In our first article in this series, we took a look at how Walnut’s National Hardwood Lumber Association (NHLA) grading scale differs from the grading scale used for other hardwood species for both First and Seconds (FAS) and Select grades. In this article, we’ll take a look at the differences in grading for Walnut at both the #1 Common and #2 Common grade levels. In each instance, you’ll notice that the standard for Walnut tends to be lower than for other species.

Walnut Grade Differences for #1 Common Grade

Common grade lumber isn’t unusable, although many purchasers won’t even consider it. This is really too bad, as it would be perfectly acceptable lumber for a variety of different applications. If you don’t mind dealing with lumber that contains some knots in it, you’ll be able to save significantly if you purchase either #1 or #2 Common grade lumber for your next project.

Typical #1 Common grade lumber must have a minimum clear cutting size of three inches by three feet or four inches by two feet. It must have a minimum board size of three inches by four feet. Both faces of the board must have 66.6% clarity.

As with the FAS and Select lumber, the standard is lowered for Walnut, which must have a clear cutting size of three inches by two feet. The percentages are the same when it comes to clarity. This difference allows smaller boards that are otherwise similar in quality to make the NHLA #1 Common grade for Walnut.

Walnut Grade Differences for #2 Common Grade

For all intents and purposes, #2 Common grade is the bottom of the barrel when it comes to what most domestic purchasers would even begin to consider for their lumber projects. Everything that falls below #2 Common grade would basically be considered too inferior to be considered even for the least important interior or exterior construction applications. Those boards would instead be relegated to use as scrap wood or for use in pallets and the like.

The clearest of the two faces for a typical #2 common grade board should have no less than a 50% clarity level. It should be a minimum clear cutting size of three inches by two feet and have a minimum board size of three inches by four feet.

Common grade is often used in hardwood flooring. That’s because small, narrow boards such as the ones that fit into this grade category are ideal for meeting the stability requirements of wood flooring. Since the bottom face will always be hidden, it doesn’t need to be very clear at all.

The NHLA grading standards for #2 Common Walnut are similar, but there is a minimum of two inches and no minimum length requirement for clear-cutting. Certainly, this lack of a minimum length tends to yield extremely small boards that are limited in their usability.

In our final article in this series, we’ll go over some of the reasons why grading standards aren’t the same for Walnut as they are for other species of lumber.