What grade of hardwood floor?          Back

When it comes to hardwood flooring, the term "grading" is sure to come up. Grading refers to the system used by manufacturers to assess the appearance of hardwood floors. The Wood Flooring Manufacturers Association grades emphasize color, grain pattern and other markings that occur in wood. Color is determined by what part of the tree the wood comes from, and grain pattern is determined by species and how the wood is cut.

Color
Heartwood, the oldest, densest, innermost section of the log, is often darker and richer in color than sapwood, which lies closest to the bark. The color difference may be so pronounced that heartwood and sapwood from the same species are marketed under separate names.

Cut
Boards can be cut from a hardwood log in several directions: tangent to the annual rings (plain-sawn or flat-sawn), or radially, across the rings (quarter-sawn and rift-sawn).

Arched or flame-shaped markings, evident in bold-grained hardwoods such as oak, characterize plain-sawn wood, while rift-sawn and quarter-sawn or "quartered" boards show a pattern of roughly parallel lines. Both have advantages depending on application and species.

Unfinished Flooring
If your choice is unfinished oak, you will have four NOFMA grades to choose from:

• Clear
• Select
• No. 1 Common
• No. 2 Common

Clear and select grades are further identified by sawing direction:

• Clear Plain
• Clear Quartered
• Select Plain
• Select Quartered

Length also plays a part in NOFMA terminology; 1 1/4" shorts, for instance, are 15-inch to 3-foot-long flooring strips. You may decide to request 1 1/4" shorts to reduce waste in bay windows and other irregular configurations.

Pre-finished
NOFMA also maintains separate grading standards for pre-finished oak flooring:

• Prime
• Standard
• Tavern

Since more than 90 percent of the hardwood flooring sold in the U.S. is oak, NOFMA grading dominates flooring. However, NOFMA also certifies maple, beech, birch and pecan flooring as first, second or third grade. First grade strips are practically free of character marks but permit natural variations in color. Second grade displays tight sound knots and other light character marks. Third grade flooring must merely provide a serviceable floor.