Wood Flooring Grading Standards
The NOFMA Standard -
You know you're getting a consistent product because NOFMA members' grades are certified.
The National Wood Flooring Manufacturers Association (NOFMA) certification requires manufacturers to meet strict standards in the four critical areas of wood flooring
manufacture: Grade, Configuration, Moisture Content and Average Length. These standards include rules for tongueand
groove fit and location, flooring thickness, end-squareness, width consistency, moisture content, average length,
and grading standards. The standards are in place to ensure that flooring purchased from a NOFMA-certified
manufacturer will fit together neatly and the installed floor will not require excessive sanding. NOFMA standards call
for moisture content at manufacture to be compatible with the range of site conditions likely to be encountered so
that the end-user can be assured the flooring will perform as expected, without experiencing excessive gaps,
cupping, crowning or buckling. NOFMA’s minimum average length requirements help ensure that expectations are
met regarding ease of installation, coverage and frequency of end-joints."
Bundles shall be 1-1/4' and longer through 8', as the stock will produce.
Appearance alone determines the grade of each hardwood flooring piece all grades are equally strong and serviceable in any application.
Flooring generally free of eye catching blemishes is known as "Clear", though it still may contain burls, streaks and pinworm holes.
"Select" is almost clear, but this grade contains more of the natural color variations and characteristics such as knots and other marks.
The Common grades, #1 and #2, have more markings than either of the other two grades and are often specified because of these widely varied
natural features and the "strong" character they bring to floors. NOFMA standard varies by grade and wood species.
SELECT & BETTER
Not over 55% of the total footage shall be in bundles under 4'; Not more than 25% of the total footage shall be in 2' bundles, and not more than 10% of the footage shall be in 1-1/4' bundles.
Ash
The face shall contain mostly sapwood, unstained.
The following characters are admitted: narrow streaks not running entire length of the strip; pin worm holes (up to 3 every 3' in length); imperfection in milling (torn grain) which will sand out; one (1) small tight knot (1/4" in diameter) to every 3' in length; small pith fleck (less than 1/4" diameter); an intermittent brown machine burn across the face not exceeding 1/4" in width; and unlimited cambium miners.
Brown heartwood is allowed as follows: 3/8" entire length or 1" for one-third the length of the strip.
Will admit pieces with 1/2 tongue. Most defect are lost sight of after the floor is laid and finished, giving a good appearance.
Red Oak
A flooring product with coloration variations produced by differences of natural heartwood and sapwood, along with characters described.
The face may contain: unlimited sound sapwood; slight imperfections in milling; a small tight knot every 3'; pin worm holes; burls and a reasonable amount of slightly open checks. Brown streaks should not extend the entire length of a piece. Two flag worm holes to every 8' are permitted. Slight imperfections in face work (torn grain) admitted. An intermittent, brown machine burn across the face not exceeding 1/4" width admitted. Also, a slight quantity of bark on the back or sides admitted. Will admit pieces with 1/2 tongue. Spot filling is generally required for open characters.
White Oak
A flooring product with coloration variations produced by differences of natural heartwood and sapwood, along with characters described.
The face may contain: unlimited sound sapwood; slight imperfections in milling; a small tight knot every 3'; pin worm holes; burls and a reasonable amount of slightly open checks. Brown streaks should not extend the entire length of a piece. Two flag worm holes to every 8' are permitted. Slight imperfections in face work (torn grain) admitted. An intermittent, brown machine burn across the face not exceeding 1/4" width admitted. Also, a slight quantity of bark on the back or sides admitted. Will admit pieces with 1/2 tongue. Spot filling is generally required for open characters.
Hard Maple
Shall have the face practically free of all defects, but the natural color of the wood shall not be considered a defect. The highest standard grade, combines appearance and durability.
Will admit the following: variations in the natural color of the wood (with use of some finishes, slight shadows and color variation may appear); an occasional small, firm pin knot, not over 1/8" in diameter, provided it does not occur on edges or ends of strips; occasional dark green or black spots or streaks not over 1/4" wide and 3" long (or its equivalent) which may contain a tight check not over 1/2" long, provided it is boxed within the piece; bird's eyes and small burls; slightly torn grain; or similar defect which can be readily removed by the ordinary method of sanding the floor after it is laid; a slightly shallow place not over 12" long on underside of the flooring if it does not extend to either end of the piece. Pieces with 1/2 tongue for no more than 25% of the length are allowed.
The wood must be sound and free of shake. Bark streaks shall not be permitted.
Bundles shall be 1-1/4' and longer through 8' as the stock will produce.
#1 COMMON
Not over 60% of the total footage shall be in bundles under 4', not more than 27% of the total footage shall be in 2' bundles; and not more than 15% of the footage shall be in 1-1/4' bundles.
Ash
A floor with varying wood characteristics such as heavy streaks, stained sapwood, and sound knots typical of this grade. All defects must readily fill and be sound.
The following characters are admitted: broken knots up to 1/2" in diameter; pith flecks less than 3/16" in diameter; worm holes up to 3/16"; checks and end splits less than 1/16" wide and not extending through the piece; and sticker stain.
Minor imperfections in machining permitted; torn grain (not over one-fourth (1/4) of the surface, less than 1/26" in depth); one (1) dark machine burn across the face for every 3' of length, not exceeding 1/2" in width, 1/64" in depth.
Will admit pieces with 1/4 tongue.
Red Oak
A flooring product which contains prominent variations in coloration and varying characters.
The following are not admitted: broken knots over 1/2" in diameter, large grub worm holes; and splits extending through the piece. Open characters such as checks and knot holes are admitted, but must be sound and readily fill. Not more than 20" scant stock in thickness allowed to every 5'. Minor imperfections in machining permitted. Shall admit sticker stain; varying wood characteristics, such as flag worm holes, heavy streaks, checks, and worm holes; and an occasional dark machine burn across the face not exceeding 1/2" wide, 1/64" deep and not more than two each 3'. 1/4 tongue allowed. Extremely dark pieces are not to be included.
White Oak
A flooring product which contains prominent variations in coloration and varying characters.
The following are not admitted: broken knots over 1/2" in diameter, large grub worm holes; and splits extending through the piece.
Open characters such as checks and knot holes are admitted, but must be sound and readily fill. Not more than 20" scant stock in thickness allowed to every 5'.
Minor imperfections in machining permitted. Shall admit sticker stain; varying wood characteristics, such as flag worm holes, heavy streaks, checks, and worm holes; and an occasional dark machine burn across the face not exceeding 1/2" wide, 1/64" deep and not more than two each 3'. 1/4 tongue allowed. Extremely dark pieces are not to be included.
Hard Maple
A floor with varying wood characteristics and colors to include distinct color variations, numerous streaks, stained sapwood, sound knots, and checks. All defects must readily fill.
Will admit the following: sound tight knots, provided they do not occur on edges or ends of strips; slight imperfections in machining; distinct color variations; sticker stain/shadow; numerous dark green or black spots or streaks, provided they do not occur in combination with predominantly dark heartwood; slight checks not exceeding 3" in length (may be slightly open) and running parallel with and well inside the edges and ends of the strips; dark spots or streaks with slight checks in center; small rough spots (torn grain) which cannot be wholly removed by ordinary method of sanding the floor after it is laid; slightly torn edges; short tongue if sufficient to hold properly in the floor; shallow or waney back, if piece has sufficient bearing of full thickness to support it in the floor; small bark streaks where bark is as sound as surrounding wood; and slight variation in angle of end matching. The face shall be free of shake and wood must be sound.
#2 COMMON
Not over 85% of the total footage shall be in bundles under 4'; and not more than 55% of the total footage shall be 1-1/4' bundles.
Ash
Defects of every character admitted, but should lay a serviceable floor.
The following defects are NOT allowed: soft rot; broken knots where the unsound portion extends through piece; Torn grain over 3/16" in depth; splits and open defects extending through the piece; shake and pith flecks that are soft if over 1/4" in diameter.
Knot holes and defects which will readily fill are admitted.
A limited number of pieces with no tongue and limited number of pieces that are thin (scant) in thickness but will end match admitted.
Red Oak
May contain sound natural variations of the forest product and manufacturing imperfections. The purpose of this grade is to furnish a floor suitable for homes, general utility use, or where character marks and contrasting appearance is desired.
The following are not admitted: shattered or rotten ends, large broken knots, excessive bad millwork, shake, advanced rot, and similar unsound defects. Dark machine burns exceeding 3/64" deep not admitted. Knot holes and open characters which will readily fill are admitted. A limited number of pieces with no tongue which may be face nailed are admitted.
White Oak
May contain sound natural variations of the forest product and manufacturing imperfections. The purpose of this grade is to furnish a floor suitable for homes, general utility use, or where character marks and contrasting appearance is desired.
The following are not admitted: shattered or rotten ends, large broken knots, excessive bad millwork, shake, advanced rot, and similar unsound defects. Dark machine burns exceeding 3/64" deep not admitted. Knot holes and open characters which will readily fill are admitted. A limited number of pieces with no tongue which may be face nailed are admitted.
Hard Maple
Must be of such character as will lay and give a good serviceable floor. The wood must be firm, serviceable and may contain all defects common to maple. Pieces with 1/4 full tongue admitted.
Third grade will not admit- knot holes over 3/8" in diameter or unsound knots where the unsound portion is over 1" in diameter; voids on ends or edges; or shake, heart checks, badly split ends and imperfections in manufacture which would materially impair the serviceability of the floor.
Bundles shall be 1-1/4' to 8', as the stock will produce.
#3 COMMON
May contain natural variations of the forest product and manufacturing imperfections. The purpose of this grade is to furnish a floor suitable for cabins, utility use, or where character marks, material defects, contrasting appearance and low cost is desired. Some pieces may not be usable it is recommended that the customer add 10 to 15% waste to their order.
"Where the Cedar Meets the Redwood"
Log Home Interior Wood paneling
