WOOD SERIES : Wood Basics II
Hardwood lumber is graded on the size and number of cuttings that can be obtained from a board when it is cut up and used in the manufacture of a hardwood product. The National Hardwood Lumber Association rules were designed with the furniture trade in mind to provide a measurable percentage of clear, defect-free wood for each grade. The upper grades provide the user with long clear pieces while the Common grades are designed to be re-sawn into shorter clear pieces.
Measurement of kiln dried lumber
Net Tally: The actual board feet of KD lumber measured after kiln drying. All lumber sold at KJP uses Net Tally counts unless specified clearly as Linear Feet
Gross Tally: The actual board feet measured before kiln drying. Because of the shrinkage in the kiln drying process, the buyer can expect to receive approximately 8% less BF
Surface Measure (SM)
To determine the SM (surface area of a board in square feet), multiply the width of the board in inches by the length of the board in feet and divide by 12. The & of clear wood required for each grade is based on SM and not BF.
FAS: "First and Seconds" will yield the user long, clear cuttings. Minimum board size is 6" and needs to be 8' or longer. The boards must be at least 83-1/3% clear-wood cutting over the entire surface. Both faces must meet this requirement.
FAS One Face (F1F) : The better face must meet all FAS requirments while the poor face needs to be a 1COM or better.
Selects: Virtually the same as F1F except allows 4"+ wide boards and 6' or longer in length. Most of what KJP purchases is Selects or Better - in this case F1F or FAS.
Number 1 Common : Boards can be a minimum of 3" wide and 4' long. The clear face cuttings only need to yield 66-2/3%. Often a better value purchase if the buyer has time to cut out the clear cutting units on each board.
Number 2A and 2B: Most commonly used for flooring since the allowable pieces are much smaller.
*sections and data compiled from the American Hardwood Export publication "The Illustrated guide to American Hardwood Lumber Grades".