Far from straightforward, hardwood lumber grading can be quite confusing for customers. And we’d like to help un-muddy those waters a bit for you today. We’ll start with a little history lesson and then describe specific grading categories. In a second post, we’ll define some key terms used in the grading system before interpreting them.
History of the Hardwood Grading System
Did you know that the hardwood lumber industry has held to the same grading standard for over 100 years? The National Hardwood Lumber Association, or NHLA, established a grading system in 1898, helping bring order to the former chaos of the lumber trade. The NHLA implemented a standardized grading system that offered a simple way to describe a board according to its quality and the area of clear wood each contained. While it may fall short in some ways, it certainly made the lumber industry far easier to navigate than the former system — or lack thereof.
Limitations of the Hardwood Grading System
Keep in mind that the NHLA grading system applies only to domestic, North American hardwood species. Exotic species such as Teak, Ipe, and Mahogany are not graded according to the same standards. In addition, this grading system was set up when the furniture industry was at the forefront, when it came to hardwood lumber usage. So the grading system was set up primarily to serve them. While the specifications make sense for furniture makers, who will cut away large portions of a board in order to make furniture pieces, they don’t always serve the needs of other industries.
NHLA Grading Categories
The top category is referred to as FAS and requires both faces to have a minimum yield of 83.33% and a minimum cutting size of 4 inches by 5 feet or 3 inches by 7 feet. The minimum board size for this category is 6 inches by 8 feet.
The next category is FAS 1 Face and Select. Developed later than the other categories, this one is in between the others, with 1 face required to meet the FAS qualifications and the other face that of at least a No. 1 Common grade. The other distinction is that the minimum board size for this category is reduced to 4 inches by 6 feet.
The No. 1 Common category has an even smaller minimum board size of 3 inches by 4 feet. The minimum cutting size is 4 inches by 2 feet or 3 inches by 3 feet, with a minimum yield of 66.66%.
The final category, No. 2 & 3 Common, has the same minimum board size of 3 inches by 4 feet but a minimum cutting size of 3 inches by 2 feet and minimum yield of 50%.
To understand more of what these category requirements mean, continue reading with Part 2.