Lumber Definitions

Lumber is sold in various forms, sizes, types and cuts. These characteristics are used to describe the different types of lumber; certain projects may require one or more of these specific traits.


The strength and weight of wood is its density. Denser wood is best for furniture and building while less dense wood can be used in making aircrafts, woodworking project, and even making paper.


Texture is the wood property that determines the condition of the surface and its stability. It plays an important role in deciding how a wood is finished.


Color contributes to the personality of wood. For example, red cedar will give you a very different look and character than white pine.

Wood Grain

Each tree has its own grain pattern, so two boards of the same species can look very different. Wood grain is the direction in which the wood cell fibers grow. These variances in grain direction can have a significant impact on your project.

The grain direction is important to consider when building either structural projects or decorative projects such as furniture or crafts. For instance, when working on a structural application, a straight-grained board is generally the strongest. In more decorative projects, grain with varying characteristics can add beauty and personality to the project. Grain pattern density determines strength. As you'd expect, a piece of lumber with a tight pattern is stronger than one with a loose grain pattern.

Wood Basics

In addition to the basic lumber definitions, there are two kinds of wood from which to choose: hardwood and softwood. The terms have almost nothing to do with the actual hardness of the wood.  There are certain characteristics that are common in all wood types.

Hardwoods are the deciduous trees that lose their leaves in the fall. Although there is an abundant variety, only 200 are plentiful and pliable enough for woodworking. Hardwood trees are generally slower-growing, making the wood denser than softwoods.  These woods have a more interesting grain pattern which makes them popular with woodworkers. Much like our skin, hardwoods have microscopic pores on the surface. The size of these pores determines the grain pattern and texture. Because of this, hardwoods are classified by pore openings as either: Closed Grained (smaller pores), like cherry and maple or Ring Porous (larger pores), like oak, ash or poplar. 

Softwoods come from coniferous trees, commonly referred to as evergreen trees. Only 25 percent of all softwoods are used in woodworking. Softwoods have a closed grain (small pores) that is not very noticeable in the finished product. The most popular softwoods are cedar, fir, pine and spruce.  Softwoods are faster-growing, with straighter grain; good for framing, construction and outdoor projects.

Lumber is available in a wide variety of sizes and products. When you shop for lumber, you may notice two sizes listed -- Common and Actual. There's a good reason for this, watch our video for more info:

Hardwood Grades

Grading designation depends on the number of defects in a board. A lower grade can be perfectly acceptable, depending on placement and usage. Hardwoods are graded by the National Hardwood Lumber Association. Here's a chart to help explain the grading system. Grades are listed from highest to lowest.


 Grade Name  
  Minimum Board Size  
 Usable Material on One Face  
First and Seconds  
FAS6-in. x 8 in.83%
SelectSel4-in. x 6 in.83%
#1 Common#1 Com3-in. x 4-in.66%
#2 Common#2 Com3-in. x 4-in.50%

Softwood Grades

Softwoods are divided into two categories: dimensional lumber, with a grade based on strength, and appearance boards, which are typically used for woodworking projects. Grades listed here are from highest to lowest. 

C Select - Almost completely clear of defects. Widely used for interior trim and cabinets.

D Select - Fine appearance, similar to C Select. May have dime-sized knots.

1 Common - Best material for high quality pine with a knotty look. Knots will be tight, meaning they won't fall out, and are generally small.

2 Common - Tight knots, but larger than found in 1 Common. Often used for paneling and shelving. Very suitable for general woodworking projects.

3 Common - Knots larger than in 2 Common. Also used for paneling and shelving, but especially well-suited for fences, boxes and crates.