October 18, 2026

Lumber Grades Explained

Get lumber grades explained and you stop paying for wood you do not need — and stop selling wood for less than it is worth. A grade is not an opinion about how a board looks. In hardwoods it is a measured promise: the percentage of a board that can be cut into clear, defect-free pieces of a stated minimum size. In softwoods it is mostly about strength and appearance for building. Two different systems, two different logics, and confusing them is how buyers overpay for FAS when No. 1 Common would have done the job beautifully.

Grades connect directly to money on both sides of a listing. If you sell lumber, grade is the language your price is written in — pair this post with our guide on how to price lumber, and with how to calculate board feet so your volumes are as defensible as your grades.

Lumber Grades Explained for Hardwoods: The NHLA System

Hardwood grading in North America follows rules maintained by the National Hardwood Lumber Association (NHLA), a system built for the furniture industry: grade is set by the size and number of clear cuttings a board yields, measured on the board's poorer face. The standard table, reproduced by Woodworkers Source in its hardwood grading basics, runs like this:

Read the table as a yield contract. FAS promises long, wide, nearly clear boards — the stock for tabletops, wide cabinet doors and millwork. F1F keeps the FAS face and relaxes the back to No. 1 Common, which is all most applications ever see. Select applies the same clear-face standard to smaller boards, so a Select board is not worse wood — it is shorter and narrower wood held to the same yield. Wagner Meters' grading explainer walks the same grades in order and notes where the bottom of the scale ends up: No. 3 territory is pallet and crating stock.

No. 1 Common: The Grade That Sells the Most Furniture

No. 1 Common is the grade buyers reach for once lumber grades are explained properly. At 66⅔% clear in smaller cuttings, it yields exactly the part sizes cabinets and furniture are actually built from — door stiles, drawer sides, face frames, short panels. The clear wood is the same colour and figure as FAS from the same log; it simply comes in shorter pieces between defects. For a shop cutting parts under four feet, FAS's long clear cuttings are waste you paid a premium to throw away.

The buying skill is matching grade to cutting list. Long, wide, clear parts: FAS or F1F. Parts under two feet: No. 1 Common, and keep the difference. Flooring, rustic work and painted projects reach further down to No. 2 Common without apology — the defects are part of the look or hidden under paint.

Softwood Lumber Grades Explained: A Different Logic

Softwoods — pine, fir, spruce, cedar — are graded under separate rules administered by regional agencies, and the logic splits two ways:

• Structural grades (No. 1, No. 2, No. 3, Stud, and machine-graded MSR/MEL) rate strength and stiffness for framing. Knots matter here because they interrupt the wood's structure, not because they look bad. No. 2 is the workhorse framing grade across North America; the grade stamp on the board carries the species, mill and grade so an inspector can verify it.
• Appearance grades (Select A through D, often sold as "C & Btr" or similar) rate how clear the face is, for trim, siding and finish work where the board will be seen.

The mistake to avoid is importing hardwood thinking: a softwood No. 2 is not "worse" than a No. 1 Common hardwood in any shared sense — the numbers belong to different systems answering different questions, one about load, one about clear yield.

Grade Is Measured on Dry, Surfaced Reality

Two cautions belong in any honest lumber grades explained guide. First, grades are assessed against the board as graded — species, moisture and surfacing all frame the result, and rough-sawn lumber you grade at the mill should be re-checked after drying, because drying can open checks and move a board across a grade line. Second, log quality sets the ceiling: no sawing pattern turns a knotty, swept log into FAS. Mills that grade-saw — orienting each log and taking boards in the order that maximises clear yield — earn their premium at the log deck, not the grading table.

Grade Terms You Will Meet in Listings

Listings compress grades into shorthand, and reading it fluently is part of having lumber grades explained properly:

• FAS/1F and S&B (Selects & Better): bundled grades — packs sold as FAS and F1F together, or Select and better. Common, legitimate, and priced between the grades they mix.
• "Cabinet grade": informal trade language for No. 1 Common, earned from its dominance in cabinet work — the grade is still 1C when it is measured.
• RWL / random width and length: ungraded-for-size stock sold as it comes off the mill; the price assumes you will do the sorting.
• #2&BTR (softwood): No. 2 and better mixed — a structural pack where some boards grade above the floor grade named.
• Surfacing codes ride along with grades: S2S (surfaced two sides), S4S (four sides) and rough describe machining, not grade — a rough FAS board and an S4S FAS board are the same grade in different states of finish, at different prices.
• KD and AD: kiln-dried and air-dried. Drying method and final moisture content sit beside grade in every serious listing because they decide whether graded stock stays in grade after it moves indoors.

When a listing uses a term you cannot map to the NHLA table or the softwood system, ask the seller to state the grade basis in plain terms — the width, length and clear-yield their boards deliver. A seller grading honestly can always translate; a seller who cannot is telling you how the load was graded.

Using Grades When You Buy and Sell

Buyers: state the grade, the cutting sizes you need, and the species in every enquiry — "FAS walnut" and "1 Common walnut" are different products at different prices, and vague requests get priced at the higher interpretation. Sellers: grade honestly, photograph the poorer face (that is the face the grade is measured on), and list cutting sizes your boards actually yield. Accurate grading is what makes a listing believable at a distance.

With lumber grades explained, the next step is putting them to work: list graded stock where buyers search by the terms in this post — sell your lumber and equipment on Lumber Lookup — or browse the equipment and lumber marketplace to see how graded stock is presented. Grade is the language of the lumber trade; speak it precisely and both sides of the deal get easier.