FAS Lumber: What the Firsts and Seconds Grade Allows

FAS (Firsts and Seconds) is the top standard grade of the NHLA rules for hardwood lumber. A FAS board is at least 6 in wide and 8 ft long, and at least 83 1/3% of its surface must cut into clear face pieces of 4 in by 5 ft or 3 in by 7 ft, on the poorer face. The number of cuttings allowed grows with the board’s surface measure. Walnut and a few other species have their own modifications.

Rule	FAS (standard species)
Lengths	8 to 16 ft
Minimum width	6 in
Surface measure	4 sq ft and up
Face graded	Poorer face (both faces must meet FAS)
Minimum clear yield	83 1/3% (10/12) of surface measure
Minimum cutting	4 in x 5 ft or 3 in x 7 ft
Number of cuttings	1 to 4, by surface measure (table below)
Extra cutting	One more cutting allowed on boards of 6 to 15 sq ft if the yield is 91 2/3% (11/12)
Grades that share the FAS face rule	F1F (one FAS face) and Selects (smaller boards, one FAS face)

Figures are from the Wood Handbook summary of the NHLA rules (Table 6-1) and the American Hardwood Export Council grade summary. The NHLA rulebook, in the edition your contract names, governs. NHLA reviews its rules every four years.

How a board is graded FAS

The grader works on the poorer face and asks one question: can enough of this face be cut into clear pieces, few enough and large enough?

1. Measure the board. Width in inches times length in feet, divided by 12, gives the surface measure (SM) in square feet. A board 8 in wide and 12 ft long has SM 8. The NHLA measurement rules page covers rounding.
2. Find the yield needed. For FAS the clear cuttings must cover 10/12 of the surface. In cutting units (inches of width times feet of length), that is SM x 10. The SM 8 board needs 80 units of clear cuttings.
3. Count the cuttings allowed. The table below sets the maximum number of cuttings for that surface measure.
4. Check sizes. Each cutting must be at least 4 in by 5 ft or 3 in by 7 ft, clear on the graded face. The reverse of each cutting must be sound.
5. Check the other face. For FAS both faces must make the grade, so the poorer face decides.

Cuttings by surface measure

Surface measure (sq ft)	Cuttings allowed at 83 1/3%	With one extra cutting at 91 2/3%
4 and 5	1	Not allowed
6 and 7	1	2
8 to 11	2	3
12 to 15	3	4
16 and up	4	Not allowed

From the Wood Handbook Table 6-1 summary of the NHLA rules. The pattern in trade summaries is SM divided by 4, fractions dropped, up to 4 cuttings. The extra cutting is a concession: a board that needs one more piece can still grade FAS if the clear yield is higher, 11/12 instead of 10/12.

A worked example: a board 9 in wide and 12 ft long has SM 9. FAS needs 90 cutting units in at most 2 cuttings. A clear piece 9 in by 8 ft (72 units) plus 6 in by 3 ft (18 units) reaches 90 units, but the second piece is smaller than both minimum cuttings (4 in x 5 ft or 3 in x 7 ft), so it does not count. The board fails FAS on two cuttings. With the extra cutting it would need 99 units (SM x 11) in 3 cuttings. If it cannot reach that, it is graded lower, often F1F or No.1 Common.

FAS, F1F and Selects

Grade	Better face	Poorer face	Minimum board
FAS	FAS	FAS	6 in x 8 ft
F1F (FAS one face)	FAS	No.1 Common	6 in x 8 ft
Selects	FAS	No.1 Common	4 in x 6 ft

Many mills sell “FAS and F1F” or “Selects and Better” as one item at one price. That is a mix, not a grade. Ask for the share of FAS in the mix if both faces of your parts show. Our page on Selects and F1F covers the one-face grades in detail.

Species exceptions

The standard rule is written for the common species. Some species are graded on modified rules:

• Walnut and butternut. The NHLA species guide says the walnut rules allow smaller specifications and smaller clear cuttings, and admit sapwood without limit. Summaries cite FAS boards from 5 in wide and 6 ft long.
• Cherry. Extension summaries of the rules note that small knots not over 1/8 in across can be admitted in cherry cuttings. The NHLA species guide lists gum pockets, pin knots and pith flecks as natural characteristics of cherry.
• Color. Sapwood is not a defect in most species. A FAS board can be half sapwood. Color sorts such as white maple or heartwood-only cherry are extra specifications.

Read the species section of the rulebook for the wood you buy. Our black walnut lumber page explains what the walnut rules mean for board sizes.

When to buy FAS

Situation	FAS or a lower grade
Long rails, stiles over 5 ft, stair treads, table tops	FAS: the long clear pieces exist only here
Both faces show (open shelves, table aprons seen from both sides)	FAS, not F1F or Selects
Mostly short parts under 3 ft	No.1 Common often costs less per usable part
Painted parts with fillable marks	No.1 or No.2A Common
Wide panels glued from strips	No.1 Common usually works

Price steps between FAS and No.1 Common vary by species and market. The only reliable test is your own cut list. Run a small lot of each grade through your rough mill and compare cost per usable part. Our guide to NHLA hardwood lumber grades explains the Common grades, and the lumber grades hub lists every grade side by side.

Checking an FAS delivery

• Pull boards from several bundles and measure width, length and surface measure.
• On boards that look borderline, mark the clear cuttings with chalk and add up the units.
• Check the poorer face. A board with one perfect face and a poor back is F1F, not FAS.
• Record results against the contract rule and edition. A grade dispute under NHLA rules can go to NHLA reinspection. See pre-shipment lumber grading for agreeing checks before the lumber ships.

What to write on the RFQ

RFQ line: White oak, FAS, NHLA rules (edition named), poorer face graded, 4/4 rough, KD 6-8%, 8-16 ft with not more than 25% under 10 ft, random widths 6 in and up, 4,000 BF.

The length clause in that example is a buyer specification, not part of the FAS rule. Send your lumber RFQ with the grade, rule and edition, and we pass it to up to 3 mills or yards that carry FAS in your species and thickness.