When you buy a 2x4 from the lumberyard you may have noticed that it has a black ink stamp on it with some letters and numbers. What does this mean? It means that this piece of lumber has been inspected and approved for use as a structural piece in a home or other building.

Every time you look at a board you will automatically give it your own grade. Most times this will be an unconscious process and you will say to yourself "Wow this is a beautiful board" or maybe "This board is no good". The following information will help to put a grade to your observations.

**Lumber Grades**RGH Rough sawn lumber.

SLR1E Straight line ripped one edge.

SLR2E Straight line ripped two edges.

S2S Surface planed on both sides of the board.

S1S Surface planed on one side of the board.

Resawn A board split in half from a thicker board.

4/4 1" rough thickness.

5/4 1-1/4" rough thickness.

6/4 1-1/2" rough thickness.

8/4 2" rough thickness.

10/4 2-1/2" rough thickness.

12/4 3" rough thickness.

16/4 4" rough thickness.

FAS First and Seconds, the top grade for hardwoods.

Sel&Btr Select & Better. Includes Select & FAS boards.

#1Com Number one common grade.

#2Com Number two common grade.

**Definition of Grades**

An FAS board must be at least 6" wide and 8' long. 83 1/3% of the board must be clear. To determine cutting units the maximum number of imaginary cuts is one-quarter of the board measure. For example, a 6" x 8' board is 4 board measure. The board can be cut only once, 1/4th of 4. After this single imaginary cut the board must be 83 1/3% clear. The area of each imaginary cut must leave at least 4" x 5' or 3" x 7' sections. If a board is 8 board measure then two cuts are allowed, yielding 83 1/3% clear, each cut at least 4" x 5' or 3" x 7'. If a single cut in a 6" x 8' board does not yield an FAS grade there are additional rules. One additional cut is allowed in boards between 6 and 15 board measure if the resulting clear portion of the board is 91 2/3%.The reverse face of a board must also be FAS for the entire board to begraded as FAS.

**Select**A select board is graded exactly like FAS. The only difference is that the minimum size of a Select board is 4" x 6' (whereas an FAS board must be at

least 6" x 8'). The reverse face of a Select board can be either Select or #1 Common.

**#1 Common**A #1 Common board must be at least 3" wide and 4' long. 66 2/3% of the board must be clear. The maximum number of imaginary cuts is one-third of the board measure plus one. Surface area after each imaginary cut must be at least 4" x 2' or 3" x 3'. For example, a board 6" x 8' is 4 board measure. One third of 4 + 1 is 1. If a single imaginary cut in the board yields 66 2/3% clear where the uncut area is at least 4" x 2' or 3" x 3', the board is graded as #1 Common. An additional cut in the board is allowed if the resulting clear yield is at least 75%. This applies to boards between 3 and 10 board measure. The reverse face of a #1 Common board is always #1 Common.

**#2 Common**A #2 Common board must be at least 3" wide and 4' long, just like #1 Common. The clear yield of a board can be as low as 50% after cuts equal to half of the board measure. Surface area after each imaginary cut must be at least 3" x 2'. For example, a board 6" x 8 is 4 board measure and can be cut twice, half of four. The resulting clear area of the board must be at least 3" x 2' and at least 50% clear. An additional cut is allowed in boards between 2 and 7 board measure if the yield is 66 2/3% clear. The reverse face of a #2 Common board can be #2 Common or better. If the reverse face of aboard is #3 Common then the entire board becomes #3 Common.

**Definitions of common terms**

**Cutting**A board is made up of clear and sound portions and defects. During grading, the grader visualises the maximum clear yield of a board. A portion of a board's surface that is clear is measured. The sum of each of these clear portions is tallied and used towards grading a board. A clear portion is an imaginary

rectangle extended as far as possible between defects. For example, a clear portion, a clear cut, is bordered by four knots or four edges or a combination

thereof. A clear cut may be bordered by two knots and two edges. The remaining surface area of a board that is not classified as clear may be either sound or defect.

**Cutting to Grade**This is a more time consuming proses of specialty cutting in order to produce a number of types of lumber grades such as quarter sawn, vertical grain or figured

patterns that would not be found in plane sawn lumber.

**Clear Face Cutting**A cutting with no defects is classified as a clear face cutting. The reverse face must be sound for a clear face grading. If the back is worse than sound the face

is not classified as clear. For example, a board with no defects on its face cannot be classified as clear if the back is riddled with unsound knots. The clear face grading relies on the back to be sound.

**Sound Cutting**A sound cutting is a board that is free of rot, pith, shake and wane. A board is sound if it contains sound knots, bird pecks, stain and streaks. Soundness means the board's strength is not impaired by anything on its surface. Holes are admitted in a sound board, unless they are the entire thickness of the board, up to two 1/4" holes or one 1/2" hole per 12 cutting units.

**Cutting Units**A cutting unit is an imaginary rectangle one inch wide by a foot long, exactly 1/12th of a board foot. Cutting units are used to determine the extent of surface

features on a board during grading. A grader cuts the board in their imagination, different grades allow a minimum number of cutting units. For example, a board 9 3/8" wide by 16' long contains defects. A clear portion8 1/2" x 6' yields 51 cutting units, a 3" x 9 1/2' portion yields 28 1/2, 4" x 2 3/4' yields 11 and 3" x 3 1/3' yields 10. The sum of the cutting units is 100 1/2, about 67% of the board. A board containing 67% clear cutting units is at best #1 Common. A board would never be cut this many times, it is just a method to calculate the clear portions of the board.

** Book Matching**Book Match is a set of boards that mirror one another. They have been cut from a single log and the two faces match in grain pattern and color.

Cup

Distortion of a board across its width.

**Special Hardwood Grading Considerations**

**Red Oak, White Oak, Black Oak**Mineral streaks and spots, and streaks and spots of a similar nature, are allowed in cuttings. The total area of these streaks and spots can be no more than 8 1/3% of cuttings. Streaks and spots outside of the cuttings are allowed to any degree.

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