Abbreviated NHLA Hardwood Lumber
Cypress Grades • Doyle Log Scale • Hardwood Lumber Grades • Hardwood Defects and Character • Hardwood Measurements • Log Cross Section • Process Terminology • NHLA 2007 Rules Book (pdf 637kb)
The following rules are used for determining hardwood grades
and generally correspond to the percentage of usable lumber in a
given board of rough lumber. Due to numerous variables, exceptions,
and special grading rules applicable to certain species, the official
rules of the National Hardwood Lumber Association (NHLA) should
FAS (First & Seconds)
and F1F Grades
and highest grade represents the finest lumber yield of
the log. Generally speaking, the minimum size
board is 6" wide, by 8' long. As seen in the sample
boards to the right, this grade is virtually free of defects,
but the minimum basic yield is 83 1/3%.
& Better) Grade
to the characteristics of an FAS board, a Select board generally
has a minimum board size of 4" wide and 6' long. Commercially,
Selects are often sold as Select and Better which includes
both FAS/F1F premium grades.
#1Com (No. 1 Common
board is an economical choice for furniture manufacturers
and cabinet shops requiring moderate lengths while utilizing
narrower boards. As seen in the sample boards to the right,
this grade will yield a minimum of 66-2/3% and
has a minimum overall dimension of 3" wide by 4' long.
that utilize #1 Common grade hardwood lumber include hardwood
flooring, kitchen cabinets, solid hardwood entrance doors,
butcher blocks, workbenches and a multitude of other items.
#2 Com (No. 2 Common
Same as #1
common except admits: unlimited diameter sound or (unsound
knots), pith, pith knots, slight peck, shake and checks.
Defects are graded from a standpoint of strength.
board 4” x 6 on even 2’ increments. No open holes are permitted.
Any unsound knot must not impair the strength of the piece.
that utilize #2 Common grade hardwood lumber include hardwood
flooring, parts and component manufacturers.
Rules Book (pdf 637kb) •
Lumber Grades by Purdue University (pdf 307kb)