Wane refers to the presence of bark or the lack of wood fiber along the edge of a piece of lumber.
Understanding Wane in Lumber
Wane is a natural characteristic that occurs on the edges of sawn lumber. It happens when the saw cut doesn't completely remove the rounded surface of the log. This leaves either the remaining bark attached or simply an area where the full wood fiber is absent compared to the square edge of the board.
- Appearance: Wane typically appears as a sloped or rounded edge on the corner or along the side of a board, often showing the bark.
- Cause: It's a result of cutting lumber from a log, where the cut is made close to the outer edge, not fully squaring off the piece.
Wane and Lumber Grading
The presence and amount of wane are significant factors in determining the grade of lumber.
According to references like the information from Culpeper Wood Preservers, which mentions the Southern Pine Inspection Bureau's grading rules:
- The amount of wane varies according to lumber grade.
- Higher grades of lumber typically allow for less wane or no wane at all, indicating a more square and consistent piece of wood.
- Lower grades may permit more significant wane, as long as it doesn't compromise the structural integrity or intended use for that grade.
This means that while wane is a natural part of the wood, its extent is controlled by grading standards to ensure the lumber meets specific quality and performance criteria for different applications.
For more details on how wane affects specific lumber grades, you can consult grading rules published by organizations like the Southern Pine Inspection Bureau (SPIB).
