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Hardwood
Flooring Cuts, Grades & Construction |
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| Oak: Solid - Prefinished |
Maple, Beech, &
Birch |
Cuts &
Construction |
NOFMA: The Wood Flooring
Manufacturers Association's principal function has been to formulate and
administer industry standards on hardwood flooring. Establishing grading
rules for flooring is a major part of these standards. Prior to
November, 1999, these Official Flooring Grading Rules covered the
standards and grades for solid unfinished hardwood strip and plank
flooring in Oak, Beech, Birch, Hard Maple, Hickory/Pecan, Ash, and
Prefinished Oak. In January, 1999,NOFMA began a program for
certification of Engineered Flooring products. The program involved
establishing grading rules for engineered flooring. These new engineered
grading standards have now been incorporated in the Official Flooring
Grading Rules.
For over a half-century, NOFMA has
been the “Voice of Authority” in the hardwood floor-ing industry,
extending even to U. S. Government agencies. In 1966, the Department of
Commerce, the National Bureau of Standards, FHA and VA withdrew product
standard CS56-60, strip oak flooring, and accepted the NOFMA Official
Flooring Grading Rules as the standard for the
industry.
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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
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.
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, buit 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.
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 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. |
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Hard Maple, Beech, Birch, Pecan - Three (3) Grades:
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NOFMA Select & Better Hard Maple (shown)
NOFMA Select & Better Beech
NOFMA Select
& Better Birch
Has a 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 7'
or 8' as the stock will produce. 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. Nested bundles (standard packaging): maximum average number of
pieces under 1-1/4' shall be 8 pieces. Average length is 3'.
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NOFMA #1
Common Hard Maple (shown)
NOFMA #1 Common
Beech
NOFMA #1 Common Birch
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.
Bundles shall be 1-1/4' and longer through 7'
or 8', as the stock will produce. 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. Nested bundles (standard packaging): maximum average
number of pieces under 1-1/4' shall be 12 pieces. Average length 2
3/4'. |
NOFMA #2
Common Hard Maple (shown)
NOFMA #2 Common
Beech
NOFMA #2 Common Birch
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' and longer through 7'
or 8', as the stock will produce. 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. Nested bundles (standard packaging): maximum
average number of pieces under 1-1/4' shall be 42. Average length 2
1/4'. |
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PREFINISHED OAK GRADING RULES |
White Oak and Red Oak in STANDARD &
BETTER Grades with a natural coloration, to be separated. All other
colors and grades may be mixed Red Oak and White Oak. Grades are
established after the flooring has been sanded and finished.
PRIME PREFINISHED
OAK
This is the top grade and
the overall appearance shall be good. The face of strips shall be
selected for appearance after finishing. This grade includes
characteristics found in the unfinished grades of CLEAR and SELECT
grade.
The following characters are admitted:
unlimited sapwood and the natural variations of color; occasional small
burls; light brown steaks not more than 1/8" in width and 6" in length
or the equivalent; an occasional very small tight 1/8" knot; and limited
1/32" fine pinworm holes, may be included in any one piece when properly
filled. Will not admit pieces with less than 3/4 full tongue. Minimum
average length 3 1/4'. Bundles 1 1/4' and up.
STANDARD PREFINISHED
OAK
The face of strips may
contain sound wood characteristics which are even and smooth after
filling and finishing. This grade includes some characteristics found in
the unfinished grades SELECT, NO.1 COMMON, and NO. 2 COMMON.
The following characters are admitted; worm
holes; season and kiln checks, broken knots up to 3/8" in diameter,
minor imperfections in machining, torn grain and burns. Other characters
will be admitted if they do not impair the soundness of the floor. All
larger admitted open characters are to be properly filled and finished.
Limited unfinished/unfilled small open grade characters
permitted.
Large grub worm holes, splits extending
through the piece, shake and similar unsound defects not
admitted.
For naturally finished coloration- all the
varying color characteristics of the wood admitted to include, Sticker
Stain, and Dark Streaks up to 3/8" in width not to exceed 1" in length
for each lineal foot.
For stained finishes- all varying colorations
and streaks permitted, predominantly dark boards not permitted.Minimum
average length 2 1/2'. Bundles 1 1/4' and up.
STANDARD & BETTER
PREFINISHED OAK
A combination of
PRIME and STANDARD grade developing from the production run. Minimum
average length 2 1/2'. Bundles 1 1/4' and up.
TAVERN PREFINISHED
OAK
Should lay a serviceable
floor.A limited amount of unfilled/unfinished open characters admitted.
A limited amount of pieces with finish irregularities such as bubbles,
small skips, lines, stain/color variation, surface handling scratches,
minor trash, and the like are allowed.
The following characters are NOT admitted:
mis-manufactured boards; shattered or rotten ends; large open knots and
other unsound defects of a similar nature; pieces with less than 1/4
full tongue. Minimum average length 2'. Bundles 1 1/4' and up.
TAVERN & BETTER
PREFINISHED OAK
A combination
of PRIME, STANDARD and TAVERN grades developing from the production run.
Minimum average length 2'. |
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NOFMA GRAIN DESCRIPTIONS ( Cuts) for 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.
CONSTRUCTION TECHNIQUES
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