Random Length Grading Specifications
General Rules
Moisture Control
We recommend maintenance of 6 percent to 9 percent average moisture content following manufacture. Upon receipt of shipment, proper moisture controls must be exercised to maintain proper moisture content.
Edge-Grain Flooring
Edge-grain hardwood flooring is specially selected and consists of pieces in which the annual rings range from 30 degrees horizontal to 90 degrees vertical.
Since hard maple is generally produced from lumber sawn out of relatively small logs with varying knurls, resulting in considerable variation in a single piece, flooring shall be considered to be all edge-grain if 75 percent of each piece falls within the above-mentioned range.
Kiln Drying
Flooring shall not be considered of specified grade unless the lumber from which the MFMA-RL flooring is manufactured has been properly kiln-dried.
End Matching
All MFMA-RL flooring shall be end-matched unless otherwise specified.
Bundled Strip Flooring
Bundled MFMA-RL flooring is random length flooring bundled in average length bundles. A bundle may include pieces from 6 inches under to 6 inches over the nominal length of the bundle. MFMA-RL flooring is bundled by grade in conformance with regular grade requirements. No piece shorter than 9" is admitted.
Nested Strip Flooring
Nested MFMA-RL flooring is random length flooring bundled continuously end to end, typically in 7' or 8' bundles (6-1/2' to 8-1/2' actual length). MFMA-RL flooring is bundled by grade in conformance with regular grade requirements. No piece shorter than 9" is admitted.
Length Distribution by Grades
| Length/ Grade | Less Than 42" | Less Than 30" | Less Than 18"* |
| First | Maximum | Maximum | Maximum |
| Second & Better | Maximum | Maximum | Maximum |
| Third & Better | Maximum | Maximum | Maximum |
| Third | Maximum | Maximum | Maximum |
| Utility | Mill Option | Mill Option | Mill Option |
The above chart reflects maximum allowable average percentage of lineal footage of 2-1/4" flooring per pallet, by grade. All percentages are inclusive.
*No piece shorter than 9" admitted.
Beech and Birch Flooring
These rules also apply to beech (Fagus grandifolia) and birch (Betula alleghaniensis) flooring.
How To Specify MFMA-RL (Random Length) Northern Hard Maple Flooring
MFMA-RL (Random Length) strip flooring is specified in the same manner as MFMA-FJ (Finger Jointed) and MFMA-PQ (Parquet) Northern Hard Maple flooring. For example, when ordering, requesting or specifying MFMA-RL Northern Hard Maple flooring, specify as "MFMA-RL" and list the grade, required species and thickness. A typical specification should appear as follows:
2.1 Materials
Flooring shall be MFMA-RL First Grade Northern Hard Maple, 25/32" thick x 2-1/4" wide; T & G and EM; grade marked and stamped as produced by an MFMA member manufacturer.
MFMA-RL (Random Length) Northern Hard Maple Flooring Grading Rules
MFMA-RL (Random Length) First Grade Northern Hard Maple
The highest standard grade. MFMA maple is an extremely durable and desirable flooring for any building; particularly suitable for fine homes, apartments, churches, clubs, dance floors, gymnasiums, handball and racquetball courts, school classrooms, hospitals, hotels, offices, roller-skating rinks, and other applications where fine appearance and long wear are desired. With the use of some finishes, slight shadows and color variations may appear.
This grade of MFMA-RL Northern Hard Maple combines appearance and durability and has a face free of defects that will materially mar the appearance of the finished floor or impair its durability. A practical application of this rule will admit variations in the natural color of the wood; 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 slight check not over 1/2" long, providing it is boxed within the piece; bird's-eyes and small burls; a slightly torn grain; or similar defect which can be readily removed by the ordinary method of smoothing the floor when it is laid.
Bark streaks shall not be permitted. A slightly shallow place not over 12" long on the underside of flooring, if it does not extend to either end of the piece, and an otherwise perfect tongue, which is one-half short for 25 percent of length of piece, are admissible, but the face must be free of shake, and the wood must be live and sound.
MFMA-RL (Random Length) Second and Better Grade Northern Hard Maple
This grade of MFMA-RL maple will provide the same long life and low maintenance performance as MFMA-RL First Grade Northern Hard Maple. MFMA-RL Second and Better Grade Northern Hard Maple is an ideal choice for gymnasiums, handball and racquetball courts, multipurpose rooms, cafeterias and shops in schools, industrial plants, offices, commercial buildings, and residences.
This grade admits tight, sound knots, provided they do not occur on edges or ends of strips; two knots, each not to exceed 1/4", are permitted in a strip up to 24" in length with a maximum of four in any strip that exceeds 24" in length; distinct color variations; numerous dark green or black spots or streaks - provided they do not occur in combination with predominately dark heartwood; slight checks not exceeding 3" in length and running parallel with and well inside the edges and ends of the strip; dark spots or streaks with slight checks in center; small rough spots which cannot be wholly removed by the ordinary method of smoothing the floor when it is laid; slightly torn edges; short tongue if sufficient to hold properly in the floor; shallow or waney back if piece has sufficient bearings of full thickness to support it in the floor; and slight variation in angle of end matching. With the use of some finishes, light sticker shadow and color variations may appear. While these and similar features are admissible, sufficient attention is given to appearance to make this grade desirable and satisfactory for use in stores, schools, factories, and similar places where superficial defects and blemishes are not a real factor of consideration. The face must be free of shake, and the wood must be live and sound. Bark streaks shall not be permitted. Occasional light stain is permitted; dark stain is not.
MFMA-RL (Random Length) Third and Better Grade Northern Hard Maple
This grade of MFMA-RL maple is comprised of a mixture of all other grades of MFMA-RL Northern Hard Maple. The lowest grade admissible shall not be less than MFMA-RL Third Grade Northern Hard Maple. MFMA-RL Third and Better Grade Northern Hard Maple is suited for nearly any application where variations in appearance are not an aesthetic concern. This grade can be produced as a mill run product provided it contains a minimum of 60% MFMA-RL Second and Better Northern Hard Maple; however it can also be produced by mixing 60% MFMA-RL Second and Better Northern Hard Maple and 40% MFMA-RL Third Grade Northern Hard Maple. This grade allows defects as described in other grades of MFMA-RL Northern Hard Maple flooring.
MFMA-RL (Random Length) Third Grade Northern Hard Maple
This grade of MFMA-RL maple is an ideal choice for gymnasiums, multipurpose rooms, cafeterias and shops in schools, industrial plants, offices, commercial buildings and residences. MFMA-RL Third Grade Northern Hard Maple gives excellent performance in recreation rooms, factories, warehouses, grain storage and other farm buildings, and rooms of antique decoration where a unique floor is desired. MFMA-RL Third Grade Northern Hard Maple is suitable for kindred uses where good wearing qualities are required together with medium cost and appearance. This grade may contain all defects common to maple, but the wood must be firm and serviceable. It will not admit voids on edges or ends, or knot holes over 3/8” in diameter; partially unsound knots where the unsound portion is over 1” in diameter; or shakes, heart checks, badly split ends and imperfections in manufacture which materially impair the serviceability of the flooring for the purpose intended.
MFMA-RL (Random Length) Utility Grade Northern Hard Maple
This grade of MFMA-RL maple may contain all defects common to maple, but the wood must be firm and serviceable. MFMA-RL Utility Grade Northern Hard Maple will not admit voids on edges or ends, or knot holes over 3/8" in diameter; partially unsound knots where the unsound portion is over 1" in diameter; or shakes, heart checks, badly split ends and imperfections in manufacture which materially impair the serviceability of the flooring for the purpose intended. Individual strips in this grade have no minimum length requirements.
Rules Governing Re-inspection
Even the most experienced inspectors will occasionally misgrade some pieces. Therefore:
Shipments shall be considered to be the grade invoiced if, upon inspection by an official inspector of the Maple Flooring Manufacturers Association, 95 percent or more, in feet, is found to be of grade invoiced. Where the degrades are in excess of 5 percent, in feet, of the shipment, the degrades in excess of the 5 percent shall be the property of the manufacturer of the flooring.
The quality of the flooring in the condition in which it leaves the manufacturer is held to govern the grade, as subsequent lack of care and improper treatment in laying, sanding or finishing are not chargeable to the manufacturer.
In the event that the amount below grade is found to be 5 percent or less, in feet, of the total amount of the item, the cost of re-inspection shall be borne by the complainant. If more than 5 percent in feet, the expense shall be borne by the manufacturer of the flooring.
For dispute resolution contact MFMA. Specific "Guidelines for Re-inspection" are available upon request. In any dispute involving the grade of the flooring material where an MFMA reinspection is requested, the determination of the MFMA inspector shall prevail.
Sizes of MFMA-RL (Random Length) Tongued and Grooved Northern Hard Maple Flooring
Thicknesses
| 1/2” | 1.270cm | (12.70 mm) |
| 25/32” | 1.984cm | (19.84 mm) |
| 33/32” | 2.619cm | (26.19 mm) |
Face Widths
| 1-1/2” | 3.810cm | (38.10 mm) |
| 2-1/4” | 5.715cm | (57.15 mm) |
| 2-1/2” | 6.350cm | (63.50 mm) |
| 3-1/4” | 8.255cm | (82.55 mm) |
Care of Flooring After Delivery
MFMA-RL (Random Length) Northern Hard Maple flooring is made from lumber kiln-dried to the proper moisture content. After kiln drying, the lumber is air-cooled and cut into strips, accurately milled, carefully graded, bundled, and stored in a dry, well-ventilated warehouse.
As a valuable product, it deserves from the dealer, trucker, and floor layer the same care in handling accorded by the manufacturer. TO ENSURE the most satisfactory results in the finished floor, observe these simple precautions:
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Don't unload, truck or transfer flooring in rain or snow. If atmosphere is foggy or damp, cover with a tarpaulin.
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Don't store flooring in leaking or open enclosures.
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Don't unload flooring outside of a shelter at the jobsite.
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Don't overlook providing protected ventilation to keep relative humidity at a minimum.
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Don't store or lay flooring in a cold, damp building or directly on a concrete slab. Wait until plastering and cement work are thoroughly dried and woodwork and trim are installed.
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Flooring should be delivered to the premises a minimum of seven days before installation, or as required for acclimation. All flooring should be placed in the area into which it is to be installed to assure proper acclimation to the environmental conditions of the facility.