Besides the unique look of each species of wood, the appearance of your hardwood floor is also determined by the grade and cut of wood. Wood Grade refers to how much (or how little) of the natural characteristics of real hardwood flooring such as knots, wood tone variation, mineral streaks, etc appear in your floor. The cut of the wood is determined by the angle at which a board is cut from the log.Besides the unique look of each species of wood, the appearance of your hardwood floor is also determined by the grade and cut of wood. Wood Grade refers to how much (or how little) of the natural characteristics of real hardwood flooring such as knots, wood tone variation, mineral streaks, etc appear in your floor. The cut of the wood is determined by the angle at which a board is cut from the log.
NWFA/NOFMA Wood Grades
Grades range from a Clear Grade that is very uniform to a Rustic Grade grade that contains a beautiful array of character. The photos below are examples of the 4 basic grades of White Oak as defined by the National Wood Floor Association.
1 Common Grade
2 Common Grade
Heidelberg Flooring's Higher Standards for Walnut Grades
However, these hardwood floor grading standards were created when 4" was considered wide plank flooring and strip flooring dominated the market. Also, their short length allowance is way too short because nobody wants a bunch of 1-3’ long pieces in their wide plank floor.
So, we developed a higher standard of grading and milling to ensure that our products are better than anything else in the industry.
Heidelberg Wood Flooring's Higher Standards for Milling and Grading Specification Sheets
PDF: Solid Plank, Engineered Plank
Page Link. Solid Plank, Engineered Plank
LInks for NWFA/NOFMA Standards Milling and Grading
For many of our Pre-Finished Hardwood Flooring Products, you will notice that we simplified the grades into two categories, Premium and Natural.
Prime/Premium Grade: A combination of NWFA Clear and Select Grade. Premium Grade has overall consistent coloring with a minimal amount of wood tone variation and minimal sound character marks that blend in with overall tone.
Rustic/Natural Grade: A combination of NWFA 1 common, 2 common, and Select. Your floor will contain a variety of wood tones, unique grain patterns, knots (only knots and open character which will readily fill are allowed), mineral streaks, occasional worm holes, and other sound character marks that make up the contrasts Mother Nature intended.
The type of wood cut is determined by the angle at which a board is cut from the log. There are three cuts of wood: Plain sawn (AKA Flat sawn), Quarter sawn, and Rift Sawn and each cut produces a board of a different appearance and quality.
The most common cut in the US is plain sawn. The log is squared and sawed lengthwise in a series of parallel cuts. The annual growth rings are mixed throughout the face of the board, joining at the ends to form a “cathedral arch.” These boards are ideal for large visual areas like whole floors, tabletops, drawer fronts, sides of dressers or other similar projects. *NOTE* You’ll notice in the diagram how the wide boards are removed from the outside of the log and works towards a smaller square in the middle. That’s because most of the knots/character in wood is found in the heart of the tree. Those wide, outside boards are mostly select/clear boards.
This is the simplest way to cut a log and is a very popular method of sawing logs in Europe and Asia. Livsawn boards contain a full variety of grain characteristics. The top/bottom 25% contain the same select/better boards as you see in the Plain sawn diagram. The middle 50% is where you get the good mix. The center of the boards will contain the cathedral arches while the outside of the boards will have a straighter grain, rift and quartered mix.
Quarter sawn boards are created by first cutting a log into quarters and then making a series of parallel cuts perpendicular to the tree's rings, cutting on the radius. The grain in quarter sawn wood is relatively consistent and the growth rings (grain) will be at a 60-90-degree angle in the profile of the flooring plank. This also makes quarter sawn boards less likely to bow, warp or twist than plain sawn. This makes it a good choice for floors being placed in high traffic areas.
The final cut is rift sawn. In this cutting method, the log is still quartered, and then cut as you see on the right and in the video below. As the cuts get closer to the outside of the log the angle of the grain changes to 30-60 degrees and reducing the amount of ray flecks appearing in the wood. This makes it easy to match boards for a uniform appearance.
*The unique trait of quarter sawn boards is the ray flecks.
Ray flecks appear in flooring that cuts across the wood’s ray cells, which creates a shimmering flake figure spread over the wood.
The following video is a great demonstration of the Quartersawn process created by a fellow Hoosier company called Frank Miller Lumber Co.