NOFMA Certification

NOFMA Grading Rules 

What does NOFMA stand for?

NOFMA stands for National Oak Flooring Manufacturer’s Association, but the NOFMA standards program goes beyond oak. The certification program is administered by the National Wood Flooring Association, and the standards can be applied to many types of hardwood flooring.

 

In order for flooring to be certified through the NWFA-NOFMA program, the mill that produces the product has to be inspected twice a year. These hardwood flooring inspectors undergo a minimum of two years of training, pass an examination, and submit written reports for review.

 

And what are these highly-trained professionals looking for? During their mill visit, inspectors will check for things for things such as configuration, average board length, moisture content, and grade, to make sure that each piece of hardwood flooring leaving the mill meets the high standards for NOFMA certification.

 

NOFMA stands for National Oak Flooring Manufacturer’s Association, but the NOFMA standards program goes beyond oak. The certification program is administered by the National Wood Flooring Association, and the standards can be applied to many types of hardwood flooring.

 

In order for flooring to be certified through the NWFA-NOFMA program, the mill that produces the product has to be inspected twice a year. These hardwood flooring inspectors undergo a minimum of two years of training, pass an examination, and submit written reports for review.

 

And what are these highly-trained professionals looking for? During their mill visit, inspectors will check for things for things such as configuration, average board length, moisture content, and grade, to make sure that each piece of hardwood flooring leaving the mill meets the high standards for NOFMA certification.

 

Why have grading rules: 

  1. Grading rules group flooring with similar qualities. This will give you a degree of consistency to products from different mills. 
  2. Gives the person purchasing the product the minimum expectations of the product's appearance. This would include surface characteristics, required lengths, and milling tolerances. 
  3. These standards allow you to have confidence in the product you are purchasing. Sample boards are generally very close to the product you will receive. 

 

How does this process work: 

The wood flooring industry has taken it upon themselves to regulate the quality of the products produced. There are several different associations that have been formed. All of these associations have similar goals. The general goals of these associations include administering standards for the industry, performing quarterly mill inspections, promoting the industry, and gathering statistical information. Inspectors check for grade compliance, including milling, packaging length and acceptable moisture levels. Most of these associations promote education programs for installers and helpful literature for the public. Lumber mills join these associations to ensure the quality of their products will be comparable to other mills. Member mills will have a stamp on the bottom of their products or boxes. This indicates these products meet or exceed industry standards. Some of these self regulating associations are: National Oak Flooring Manufacturers Association, www.nofma.org, Maple Flooring Manufacturers Association, www.mfma.org, Canadian Lumbermen’s Association www.cla-ca.ca/ . Softwood flooring grades are established by the Southern Pine Inspection Bureau, Western Wood Products Association, and West Coast Lumber Inspection Bureau. If there were a question about the quality of the product received a representative of the company would come out to inspect the product and proceed with a suggested resolution. 

 

In other cases wood flooring manufacturers determine their own lumber classifications and create their own grades, or proprietary grades. The following will be a discussion of the general grading rules for solid oak and engineered oak. This will cover three of the products shown in our area. These rules are taken directly from the NOFMA web page in part. I would like to thank the NOFMA for allowing us to copy the grading rules listed below from their web pages. 

 

For the complete grading rules please visit the following location. http://www.nofma.org/gradingrules.htm 

 

NOFMA GRAIN DESCRIPTIONS 

OAK 

PLAIN SAWN 

QUARTER SAWN 

RIFT SAWN 

QUARTER/RIFT SAWN

PLAIN SAWN: flooring that is marked or specified as PLAIN SAWN or PLAIN, may contain any combination of the following types of grain classification. Also, flooring without a grain designation may contain any combination of the types of grain classification: Plain Sawn, Rift Sawn, and Quarter Sawn. 


QUARTER SAWN: flooring that is marked or specified as QUARTER SAWN or QUARTERED; at least 50% of the piece must contain Quartered characteristics. Quartered characteristics as defined by NOFMA are: In cross section the angle of the annual ring tangent to the face of the piece to be between 45° and 90°. Grain lines to be mostly parallel to the length of strips, and medullary ray flecks present and more than 1/16" wide. 


RIFT SAWN: Flooring that is marked or specified as RIFT SAWN or RIFT; at least 75% of the piece must contain Rift characteristics. Rift characteristics as defined by NOFMA are: In cross section the angle of the annual ring tangent to the face of the piece to be between 30° to 60°. Grain lines to be mostly parallel to the length of strips and medullary ray flecks less than 1/16" wide. 


QUARTER/RIFT SAWN: Flooring that is marked or specified as NOFMA QUARTER/RIFT SAWN or QUARTER/RIFT, is a combination of QUARTER SAWN and RIFT SAWN developing from the production run. 


OAK FLOORING GRADING RULES 

(NOTE: Characters included in a higher grade are automatically accepted in lower grades.) 


NOFMA CLEAR OAK 

A flooring product of mostly heartwood with a minimum number of character marks and discoloration, providing a uniform appearance while allowing for all heartwood natural color variations. Will admit the following: 3/8" bright sapwood entire length of strip or equivalent if not extending further than 1" for 1/3 length of piece; small burls and fine pin worm holes; and equivalent characters such as small tight checks; in the absence of these, one thin brown streak 3" long to be allowed every 6'. 

Standard Packaging - Bundles to be 1 1/4' and longer; Average length, bundled or nested, 3-3/4'. Shorter Packaging - Average length for 7' and shorter packages, nested or otherwise, 3 1/2'. 


NOFMA SELECT 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 wormholes 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. 

Standard Packaging - Bundles to be 1 1/4' and longer; Average length, bundled or nested, 3 1/4'. Shorter Packaging - Average length for 7' and shorter packages, nested or otherwise, 3'. 


NOFMA NO. 1 COMMON 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 filled. Not more than 20" scant stock in thickness is allowed to every 5'. Minor imperfections in machining permitted. Shall admit sticker stain; varying wood characteristics, such as flag wormholes, heavy streaks, checks, and wormholes; 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. 

Standard Packaging - Bundles to be 1 1/4' and longer; Average length, bundled or nested, 2- 3/4'. Shorter Packaging - Average length for 7' and shorter packages, nested or otherwise, 2 1/2'. 


NOFMA NO. 2 COMMON 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 are 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. 


Standard Packaging - Bundles to be 1 1/4' and longer; Average length, bundled or nested, 2- 1/4'. Shorter Packaging - Average length for 7' and shorter packages, nested or otherwise, 2'. 


NOFMA 1 1/4' SHORTS OAK 


Pieces 9" to 18" long are to be bundled together and designated as 1 1/4' Shorts. Pieces graded NO. 1 COMMON, SELECT and CLEAR to be bundled together and designated NO. 1 COMMON & BETTER with pieces grading NO. 2 COMMON bundled separately and designated as such. Although pieces 6" under and only 3" over the nominal length of the bundle may be included, the pieces must average 1 1/4', which is achieved through the natural preponderance of longer lengths. 


RETURN TO THE HOME PAGE 

NOFMA: The Wood Flooring Manufacturers Association 

Copyright © 1997-2003. All Rights Reserved. 

E-Mail: info@NOFMA.org 



  1. NOFMA Select & Better Hickory / Pecan 

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 a nearly uniform appearance with exceptional durability. 

The following characters are admitted: variations in the natural color of the wood, heartwood and sapwood: an occasional small, firm pin knot or bird peck, not over 1/8" in diameter, provided it does not occur on edges or ends of strips; dark streaks not over 1/4" wide and 3" long (or its equivalent one for every 3 ft. in length); slight checks not over 1/2" long, provided check is boxed within the piece; small burls; slight torn grain or slight intermittent machine burn; 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 that 25% of the length are allowed. The wood must be free of shake. Bark streaks shall not be permitted. 

Packaging: 8' or shorter, nested or bundled. Pieces/bundles shall be 1 1/4' and longer through 7' or 8' as the stock will produce (9" Minimum, 102" Maximum). Average length 3 1/4'. Average length for 7' and shorter packages, nested or otherwise - 3'. 


NOFMA #1 Common Hickory / Pecan 


A floor with varying wood characteristics and colors to include heavy streaks, stained sapwood, sound knots, checks and small splits. All defects must readily fill and be sound. 

The following characteristics are admitted: broken knots up to 1/2" in diameter; distinct color variations (predominantly dark, discolored pieces not allowed); sticker stain/shadow; numerous dark streaks or black spots; checks to 1/16" not exceeding 3" in length, and running parallel and well inside the strip edges; small end split 1/16" x 1/2" showing no movement; bird pecks to 1/2" where bark is sound and as hard as surrounding wood. 

Minor imperfections in machining permitted; torn grain (less than 1/16" deep and 3" long for full width); slightly torn edges, and an occasional dark machine burn 1/2" in width (1 per 3'). Will admit pieces with 1/2 full tongue the entire length of the piece. 

Packaging: 8' or shorter, nested or bundled. Pieces/bundles shall be 1 1/4' and longer through 7' or 8' as the stock will produce (9" Minimum, 102" Maximum). 

Average length 2 3/4'. Average length for 7' and shorter packages, nested or otherwise- 2 1/2'. 


NOFMA #1 Common & Better Hickory / Pecan 


A combination of NOFMA Select and NOFMA #1 Common developing from the production run. The lowest graded pieces allowed are NOFMA #1 Common. 

Packaging: 8' or shorter, nested or bundled. Pieces/bundles shall be 1 1/4' and longer through 7' or 8' as the stock will produce (9" Minimum, 102" Maximum). Average length 2 3/4'. Average length for 7' and shorter packages, nested or otherwise- 2 1/2'. 


NOFMA #2 Common Hickory / Pecan 

Must be of such character as will lay and give a good serviceable floor. The wood must be firm, and may contain defects of every character. This grade is intended to give a "rustic" appearance. 

The following defects are not allowed: knot holes over 3/8" in diameter or unsound knots where the unsound portion is over 1" in diameter (the unsound portion can not extend through piece); shake, soft rot, splits and open defects which extend through piece or show movement, torn grain more than 1/4" deep, edge splinters, and imperfections in manufacture which would materially impair the serviceability of the floor. Knot holes, bird pecks, wormholes, and the like which will readily fill are admitted. Pieces with 1/4 full tongue admitted. 

Packaging: 8' or shorter, nested or bundled. Pieces/bundles shall be 1 1/4' and longer through 7' or 8' as the stock will produce (9" Minimum, 102" Maximum). Average length 2 1/4'. Average length 7' and shorter packages, nested or otherwise- 2'. 


NOFMA #2 Common & Better 


A combination of NOFMA Select, NOFMA #1 Common, and NOFMA #2 Common developing from the production run. The lowest graded pieces allowed are NOFMA #2 Common. 

Packaging: 8' or shorter, Nested or bundled. Pieces/Bundles shall be 1 1/4' and longer through 7' or 8' as the stock will produce (9" Minimum, 102" Maximum). Average length 2- 1/4'. Average length for 7' and shorter packages, nested or otherwise- 2'. 


SPECIAL GRADES 

Hickory / Pecan 

NOFMA Clear Red Hickory / Pecan 

Is a special stock selected for its deep red/brown color with the minimal contrast of the lighter sapwood. 

Face of the piece shall be heartwood (95%). All NOFMA Select Hickory / Pecan Grade Rules apply. 


NOFMA Clear White Hickory / Pecan 

Is special stock selected for its creamy color with the minimal contrast of the darker heartwood. The face of pieces shall be bright sapwood (95%). All NOFMA Select Hickory / Pecan Grade rules apply. 

EXCEPTIONS: streaks should be light brown not over 1/4" wide and 3" long (or equivalent) one per 3'. black spots not allowed, sticker stain/shadow none allowed. 

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NOFMA: The Wood Flooring Manufacturers Association 

Copyright © 1997-2003. All Rights Reserved. 

E-Mail: info@NOFMA.org 

ENGINEERED HARDWOOD FLOORING 

The NOFMA definition of Engineered Hardwood Flooring... A product which is an assembly of multiple layers of hardwood veneer or dimensioned stock. The layers are kiln dried; assembled with opposing grain direction (cross-hatched); and bonded together to form a single unit. The unit is milled on all edges and surfaced. The engineered flooring product must be glued, stapled or nailed to a proper sub- strate, as recommended (specified) by the manufacturer. 

Engineered flooring is a kiln dried product with an average moisture content between 5 and 11% MC at time of shipment. Edge configuration options include: a tongue and opposing groove; bevel edges and ends; bevel edges and non beveled ends; and a fully jointed or square edge, with or without face bevels. Jointed or square edges are most common with parquet units. 

NOFMA members are required to mark their product with an identifying number/name and to identify the species of the face veneer. 

Products may include strip, plank, and parquet, both unfinished and factory finished. 

NOFMA ENGINEERED FLOORING UNFINISHED GRADES 

GRADING RULES 

  1. NOFMA SELECT & BETTER ENGINEERED - OAK 

An engineered flooring product with col-oration variations produced by differences of natural heartwood and sapwood along with characters and other color variations described. The face may contain the following specified characters and equivalent variations: one small tight knot or slightly open pin knot every 3’; pin worm holes; unlimited burls; scattered slight checks over less than 1 /3 of piece; limited amount of small open checks to 3 “ long; brown streaks should not extend the entire length of piece; a limited amount of dark brown streaks 1 /8 ” wide and less; and stained sapwood if a uniform light gray color. The face may contain the following imperfections in machining and equivalent variations: slight edge and corner breakage; slightly open splice lines and joints to 2” long; torn grain which will sand out; occasional indented or crushed fibers; slight fiber tear out around veneer plugs; an intermittent machine burn across the face; and slight splintering or rough grain if able to brush/rub off easily. The face may not contain the following: rot, shake, delaminations, sander dips, bit ends, and splintering. Core laps are not allowed. 

NOFMA NO. 1 COMMON ENGINEERED - OAK 

An engineered flooring product which con-tains prominent variations in coloration and varying characters. The face may contain the following specified characters and equivalent variations: unlim-ited tight knots to 3 /4 ” diameter with 1 /16 ” wide cracks; occasional shot worm holes; angled pin worm holes extending to 1 /2 ” across the face; sound bark pockets with slight openings; unlimited checks less than 1 /16 ” wide; 1 /16 ” x 2” checks, one per foot; and heavy mineral streaks, dark flag wormholes, and prominent splotchy stain where dark discoloration is less than 50% of piece. The face may contain the following imperfections in machining and equivalent variations: minor edge and corner breakage not extending below face veneer and with no splintering; readily fillable joints and lines at splices; unlimited diagonal splices; an occasional area of torn grain to 1 /16 ” deep; small indentations to 1 /16 ” deep; slight fiber tear out around veneer plugs; unlimited rough grain if not containing loose splinters; two 1 /2” wide dark machine burns per 3’ across the face; and a slightly bit end. The face may not contain the following: rot, shake, delaminations, sander dips, and splinters which are not easily rubbed/brushed off. Core laps are not allowed. 

NOFMA NO. 2 COMMON ENGINEERED - OAK 

An engineered flooring product which may contain sound natural variations of the forest product and manufacturing imperfections. The face may contain the following specified characters and equivalent variations: unlimited tight knots and broken knots with 3 /8 ” maximum opening; fillable cross-face wormholes, flag wormholes, and grub worm holes; bark pockets with maximum 3 /8 ” open or unsound area; unlimited open checks smaller than 1 /8 ” and one check per piece 1 /8 ” x 6”; unlimited dark coloration, mineral streaks, and splotchy/speckled stain; and unlimited sound rot with scattered pitting. The face may contain the following imperfections in machining and equivalent variations: edge and corner breakage to 3 /16 ” x 1” or equivalent, depth not considered; readily fillable joints and lines at splices with 1 /32” or smaller openings; unlimited diagonal splices; a full width area of torn grain 3” long to 1 /8 ” deep every 2‘; indentations to 1 /4 '' deep; 1 /16 ” fiber tear out around veneer plugs; unlimited rough grain if not containing loose splinters; dark machine burns not deeper than 3 /64 ”; and a bit end to 1 /16 ” deep. The face may not contain the following: shake, delaminations, and splinters which are not easily rubbed/brushed off. Core laps are allowed if not sanded through on the face ply. 

  1. NOFMA ENGINEERED FLOORING FACTORY FINISHED GRADES 

GRADING RULES 

NOFMA PRIME ENGINEERED - OAK

This is the top grade and the overall appearance shall be good. This grade includes characteristics and variations in coloration which when properly filled, appropriately colored, and finished yield a flooring product with a uniform appearance requiring only minor remedial repair after installation. 

The face may contain the following specified characters and equivalent variations: sound tight knots or filled cracked knots, average 1“ diameter; open pin worm holes and filled wormholes no greater than  1/4 ”; sound bark pockets with a small filled opening; unlimited slightly open checks, limited open checks to 1 /64 ”, and filled checks to 1 /16 ” x 3”; sound rot which blends with finished color; unlimited mineral streaks in darker stained finishes, brown mineral streaks in lighter stained finishes; and unlimited stain in dark finishes and stain which blends with lighter finishes. The face may contain the following imperfections in machining and equivalent variations: slight edge and corner breakage, may be unstained; slightly open splice lines and joints to 2” long; rough grain sanded smooth and covered with finish; slight chatter; occasional indented or crushed fibers; slight fiber tear out around veneer plugs, filled; and slight splintering if able to brush/rub off easily. The face may contain the following imperfections in finishing and equivalent variations: slight orange peel, intermittent white grain, and slight amount of rough finish. The face may not contain the following: shake,  delamination, sander dips, splintering, crushed grooves, finish/stain skips, dark or light ends, and debris within the 

finish. Core laps are not allowed. 

NOFMA CHARACTER ENGINEERED FLOORING - OAK 

An engineered flooring product which contains prominent contrasting wood color variations, small open unfinished characters, along with properly filled characters and minor finish irregularities. The face may contain the following specified characters and equivalent variations: unlimited sound knots with open cracks to 1 /8 ”; open wormholes to 1 /8 ” and filled wormholes to 3 /8 ”; bark pockets with up to 1 /32 ” x 1“ filled opening; open check and splits to 1 /16 ” x 3”; sound rot; unlimited mineral streaks and stain; and a slight amount of shake. The face may contain the following imperfections in machining and equivalent variations: edge breakage up to 1 /8 ” x 1“ and corner breakage to 1 /8 ” x 1 /4 ”, limited to face ply, may be unstained; slightly open splice lines; unlimited diagonal splices; rough grain sanded smooth and covered with stain; slight chatter; indented areas to 1 /16 ” deep; small amount of fiber tear out around veneer plugs; and slight splintering if able to brush/rub off easily. The face may contain the following imperfections in finishing and equivalent variations: slight orange peel, slight amount of white grain, speckled stain which blends with finish color, a small amount of minor debris, light or dark ends which show no contrast, and slight amount of rough finish where gloss is not dulled. The face may not contain the following: delamination, sander dips, splintering, and crushed grooves which prohibit engaging planks. 

NOFMA CABIN ENGINEERED FLOORING - OAK 

An engineered flooring product which contains prominent contrasting wood color variations, both filled and open characters, and some finish and manufacturing irregularities. The face may contain the following specified characters and equivalent variations: unlimited sound knots with open cracks to 1/4”; worm holes to 1 /4 ” and filled worm holes to 1 /2 ”; bark pockets with up to 3 /8 ” opening; open checks and splits to 1 /16 ” x 3”; unlimited sound rot with scattered pitting; unlimited mineral streaks and stain; and shake where color shows no major contrast. The face may contain the following imperfections in machining and equivalent variations: edge breakage up to 1 /8 ” x l “and corner breakage to 1 /8 ” x 1 /4 ”, may be unstained; open splice lines to 1 /32 ”; unlimited diagonal splices; rough grain with no loose splinters; moderate chatter; indented areas to 1 /4 ” x 1 /2 ”; 1 /16 ” fiber tear out around veneer plugs; and slight splintering if able to brush/rub off easily. Core laps allowed if not sanded through face ply. The face may contain the following imperfections in finishing and equivalent variations: moderate—orange peel, top coat irregularity, finish skips, stain skips, rough finish; unlimited white grain showing no prominent contrast, unlimited speckled stain, debris to 1 /4 of piece, light and/or dark ends, and wood filler along edge if pieces engage. The face may not contain the following: delamination, sander dips, splintering, and crushed grooves which prohibit engaging planks. 

RETURN TO THE HOME PAGE 

NOFMA: The Wood Flooring Manufacturers Association 

Copyright © 1997-2003. All Rights Reserved. 

E-Mail: info@NOFMA.org