The Complete Lumber Buyer’s Guide

Your first trip to the lumber yard can be a nerve-wracking experience. If you’ve ever been around a woodshop for a day, you know that woodworking is a language all its own. The same is true for lumber yards: not knowing the correct terminology can make a stressful trip that much more overwhelming. Thankfully, there’s only a small set of terms you need to learn in order to look like an old pro during your first visit to the lumber yard.

This article covers four categories of wood terminology you will encounter at any lumber yard:

  1. dimensions
  2. grades
  3. cuts
  4. pricing

Lumber Dimensions

Many people begin their woodworking experiences with construction-grade lumber from a local home center (2x4s, 4x4s, 2x12s, et cetera). While this type of wood has many uses and is an ideal material for certain projects, the quality and characteristics are different than what you’d find at a lumber yard. If you ask for a 2×4 of cherry or walnut at a lumber yard, you might get a few blank stares, snorts of laughter, or a mix of the two.

At lumber yards, the dimensions of hardwoods (and some softwoods) are grouped into quarter-inch increments that describe the lumber’s thickness. The first and smallest size is 4/4 (or one inch) pronouncedfour quarter. The most common sizes found in lumber are:

  • 4/4 —four quarter
  • 5/4 —five quarter
  • 6/4 —six quarter
  • 8/4 —eight quarter
  • 12/4 —twelve quarter
  • 16/4 —sixteen quarter

Unlike construction lumber, like 2x4s that use nominal sizing (2” x 4” is really 1.5” x 3.5”), a four quarter board is actually 1” thick. When purchasing lumber for a project, always get boards that are slightly thicker than your desired final thickness. If you are building a table and want the top to be one inch thick, buy 5/4 or 6/4 boards instead of 4/4 boards so that you have extra thickness for surfacing and sanding.

Lumber Grades

Each North American hardwood species you will find at a lumber yard has a grade. This grade is a part of the National Hardwood Lumber Association (NHLA) standards, and it specifies the amount of clear wood and acceptable yields for a given board.

There are two categories of grades:

  1. First and Seconds (FAS)
  2. Common

FAS boards have fewer defects and are more expensive than common boards, but that doesn’t mean they are always the best choice. FAS and common boards specify a minimum threshold of clear wood. It’s not uncommon to find 100% clear boards, but even the highest grade of wood doesn’t guarantee that a board will be completely clear.*

*These lumber grades refer to North American hardwoods only. Softwoods like pine, fir, and cedar will not be graded according to this system. Neither will exotic species like mahogany, sapele, or teak.

FAS (First and Seconds)

Both faces of the board must meet the following criteria.

Minimum Clear Yield Minimum Board Size Minimum Cutting Size
83.33% 6” x 8’ 4” x 5’ or 3” x 7’

FAS 1 Face

One face of the board must meet the following criteria. The other face must meet the standards of at least No. 1 Common.

Minimum Clear Yield Minimum Board Size Minimum Cutting Size
83.33% 6” x 8’ 4” x 5’ or 3” x 7’

FAS Select

Select has the same requirements as FAS 1 face, however, the minimum board size is slightly reduced.

Minimum Clear Yield Minimum Board Size Minimum Cutting Size
83.33% 4” x 6’ 4” x 5’ or 3” x 7’

No. 1 Common

The common rated species have a significantly decreased minimum clear yield and minimum board size compared to FAS. Depending on your project, they can be a great bargain.

Minimum Clear Yield Minimum Board Size Minimum Cutting Size
66.67% 3” x 4’ 4” x 2’ or 3” x 3’

No. 2 & 3 Common

No. 2 and No. 3 Common the same minimum board size as No. 1 Common, but the minimum clear yield decreases dramatically.

Minimum Clear Yield Minimum Board Size Minimum Cutting Size
50% (No. 2) 33% (No. 3) 3” x 4’ 3” x 2’

Wood Defects

Each wood grade specifies a minimum clear yield: the minimum acceptable amount of defect-free wood on a board’s face. To fully understand what this means, let’s look at what the NHLA classifies as acceptable and unacceptable defects.

Acceptable Wood Defects

Defects that don’t affect a board’s rating

  • Burl
  • Glassworm
  • Gum streaks
  • Mineral streaks
  • Sticker marks
  • Sapwood

Unacceptable Wood Defects

Defects that affect a board’s rating

  • Bark pocket
  • Bird pecks
  • Checks
  • Decay
  • Grub holes
  • Knots
  • Pith
  • Splits
  • Sticker stains
  • Wane
  • Worm holes

Experienced woodworkers will often use defects to their advantage. For instance, a board with bark inclusions, knots, or wane could have unique character the attracts a furniture maker. Based on NHLA guidelines, a board with those qualities would likely receive a lower common grade and therefore be much cheaper than an FAS board of the same species.

Pre-Surfaced Lumber

The last type of lumber we’ll talk about is pre-milled or pre-surfaced lumber. It’s also worthy to note that this is likely the only way you’ll find hardwood sold at your local home center (like Home Depot or Lowes).

Rough lumber is the most common type of lumber you’ll encounter at a lumber yard. It’s called “rough” because the boards haven’t been jointed flat on either face or side. Most lumber yards offer pre-surfaced lumber in addition to rough lumber. Pre-surfaced lumber is more expensive. If you have access to a jointer and a planer you may want to thinking about milling the boards yourself; for those who don’t, or who don’t wish to mill their own lumber, here’s the terminology to know:

  1. SxS (Surfaced x Sides)– Pre-surfaced lumber is designated by how many sides have been surfaced and made flat and square.
  2. S2S– Each face of the board has been made flat and parallel to one another, but the edges remain rough.
  3. S3S – Each face of the board has been made flat and parallel to one another and one edge has been jointed square to the faces.
  4. S4S – Each face of the board has been made flat and parallel to one another. Each side of the board has been made flat and parallel to one another and square to the faces.

Lumber Cuts

There are three main ways lumber can be sawn from a log: flat or plain sawn, quarter sawn, and rift sawn. These cuts reveal different grain patterns and characteristics in a board. Flat or plain sawn boards are the most typical cut you’ll see, and are also the cheapest. Quarter sawn boards in the same species are usually twice as expensive as flat sawn boards, while rift sawn boards are usually slightly more expensive than quarter sawn boards.

When at a lumber yard, don’t expect to find each species of wood carried in each type of cut. Quarter and rift sawing lumber is time-intensive and creates a lot of waste in the process, which is why you have to pay a premium compared to that species’ flat sawn variety.

Certain cuts are also more sought after in different wood species than others, which influences the types of cut a lumber yard will stock for a certain species. Quarter sawn white oak, for example, is commonly associated with Arts and Crafts furniture, and rift sawn cherry is prized for its calm and clean lines in contemporary furniture. For these reasons it’s unlikely that you’ll ever find rift sawn white oak or quarter sawn cherry.

Flat or plain sawn lumber is the most common and cost efficient way to cut a log. In this method, logs are cut in series along their latitude. A full width flatsawn board will have sections of grain that match each type of cut: vertical, quarter sawn grain on the edges of the board; large cathedral-grain in the center of the board; and diagonal, rift sawn grain between the two. Because flat sawn boards contain all types of grain, the growth rings of the wood are not uniform along a board’s face. While this can create interesting effects and certainly has a place in furniture design, it makes flat sawn boards less stable to structural strain and humidity changes.

Quarter sawn lumber is called “quarter” because the log is first cut into 4 wedges. Each wedge is then oriented so that the log is cut to reveal vertical grain running along the board’s face. The grain uniformity and arrangement makes quarter sawn boards incredibly stable to physical forces and moisture changes.

Rift sawn lumber is the most difficult way to cut a log and leaves behind the most unusable material. Rift sawn boards are similar to quarter sawn boards in that they both have grain running vertically along their faces, however where the end grain on quarter sawn boards is up and down, the end grain on rift sawn boards is diagonal. The main advantage to this is that all four sides of the board have relatively uniform and vertical grain. This makes it a good option for certain table legs. Another advantage is if one wants the quarter sawn look without any ray fleck.

Lumber Pricing

The two primary lumber pricing methods are by board foot or by linear foot. Price per board foot is the most common, but it’s good to know the difference.

Linear Foot (LF)

Lumber that’s priced by linear foot is typically wood that’s been pre-milled and cut to a specific width. The only factor you need to consider when determining what a board will cost is its length. For example, if walnut cost $5 per linear foot, then a 10 foot board would cost $50 (10 feet x $5 per foot).

Board Foot (BF)

Lumber that’s priced by board foot is most commonly random-width lumber. This is wood that’s not cut to a specific width before being sold. Lumber yards use a simple formula to determine how many board feet are in a specific board: multiply the surface area of a board (sq ft.) by its thickness (in.)

Examples:

A board that’s 1” thick, 12” wide, and 12” long:
(1 inch thick) x (1 foot wide) x (1 foot long) = 1 board foot of lumber

A board that’s 2” thick, 6” wide, and 36” long:
(2 inch thick) x (0.5 feet wide) x (3 feet long) = 3 board feet of lumber