The Lingo of Lumber – Understanding Hardwood Lumber Grading Terms

The first time you go to a hardwood dealer can be pretty intimidating. It can be like stepping into a foreign country where they speak a different language. Here’s an example: You walk into the lumber warehouse and you think you’ve died and gone to heaven. Wood as far as the eye can see. Every conceivable species just waiting to go home with you. This alone can make your head spin. While you’re picking your chin off the floor an employee comes up and asks if they can help. You come to your senses and and finally spit out that you’re looking for some walnut. “Well,” he says, “do you want that FAS, Select, No. 1 Common? What size do you want it, 4/4, 5/4, 6/4, or 8/4? Do you want it air dried or kiln dried?” And you thought your head was spinning before! What language is this guy speaking, “lumbernese”?

Armed with the right information you can avoid this scenario altogether. Lumber has its own grading system that the United States and Canada uses that is set by the National Hardwood Lumber Association (NHLA). This association was formed in 1897 to standardize hardwood grading because before each mill had their own grading system (and you thought the example above was confusing).

The grading of hardwood is based solely on the two faces of a board, and how wide it is, the thickness of the board doesn’t come into play. When grading hardwood lumber the worst side (face) of a board is usually used to grade that board (sometimes the best face is considered). There are eight grades of hardwood lumber.

FAS: First and Seconds. This used to be two separate categories but was combined many years ago. FAS is the best grade of lumber meaning that it has the largest percent of clear area over all the other grades for this species of wood. And as you would guess it’s also the most expensive. A board must be at least 6″ wide and the poorer of the two faces is used to grade it.

FAS 1-Face: First and Seconds One Face. Similar to FAS except the better face is graded instead of the worst. It must also be 6″ wide.

Select: Select is No. 1 Common on one face and FAS on the other. The board must be at least 4″ wide and like FAS 1-Face, the better face is graded. The price between the first three grades can be very similar depending upon the dealer.

No. 1 Common: This grade is often times just called No.1 or Common. This is still furniture grade material but more defects are allowed than the previous grades. Poorer side is graded and must be 3″ wide.

No. 2A Common: You can still get short to medium size pieces that are furniture grade material. Poorer side is graded and must be 3″ wide.

No. 2B Common: Much the same as 2A Common.

No. 3A Common: Worm holes are allowed in this grade, other wise the same as 2B Common.

No. 3B Common: Used in pallets and crates, graded on the soundness of the board rather than defects.


The thickness of hardwood lumber is measured in 1/4″ increments. The measurement is taken before the board is surfaced. Expect to have to take off at least 3/16″ – 1/4″ in thickness to get a smooth flat surface on both sides. Remember to take this into consideration when buying stock for a project.

4/4 = 1 inch

5/4 = 1 1/4 inches

6/4 = 1 1/2 inches

8/4 = 2 inches


Armed with this information you can confidently walk into your hardwood dealer and talk “lumbernese” with the best of them.