How To Buy Lumber

When it’s time for your next DIY project, you may need to shop for lumber. With a little understanding of the basics, choosing the right boards can be a very simple task.

Determine What Kind of Lumber You Need

How you plan to use your lumber will determine which type you need to buy.

For some projects, the appearance of the wood will be important. For example, you may be making a cabinet or piece of furniture that will be stained or varnished. In this case, choose lumber that is graded 'premium' or 'select.' These terms refer to a piece of lumber's lack of knotholes, unattractive color variations or other major imperfections.

For other projects, the wood's appearance won't matter much or you plan to paint the wood. In these circumstances, select 'common' grade pieces of lumber. Common grade lumber may contain imperfections, but it is much less expensive than premium or select grades.

Make Sure It’s Straight

When choosing lumber, make sure the pieces are straight, not warped or overly curved. The test may require some practice.

  1. Hold one end of the board up to your cheek, just below one of your eyes. 
  2. Close your other eye and look down the narrow edge of the lumber.
  3. You should be able to determine if the lumber is straight or not.

If the lumber appears to be curved or warped - choose another piece.

Check for Arches

Lay the piece of lumber on a level ground or floor surface. Both ends of the wood should lie flat on the surface, and there should be no bows or arches visible. Ensure that  there are no bows or arches in the center of the wood as well. The wood should rest completely flat on a level floor surface.


If you'll be using the lumber outside, or if the wood will be exposed to the elements, then you should select pieces that have been specially treated to resist bowing and damage caused by water. This type of lumber is generally referred to simply as 'treated lumber' or 'waterproof lumber.' Keep in mind, however, that these pieces may be more expensive that untreated boards.