ALL ITEMS READY TO SHIP WITH FREE PRIORITY MAIL WITHIN THE US!

Lumber Dimensions Guide

Using dimensional lumber from the hardware store is a great, easy way to make DIY shelves. It comes in a variety of wood species, is easy to find, and the store will likely cut it to the desired length (meaning you can make shelves without any power tools!). However, there is a lot of confusion with how the sizing is labeled. Here, we'd like to clear that up for you! 

lumber dimension guide

Nominal sizes (what it's called at the local hardware store, such a 2" x 4") is the size of the board before it's been planed at the mill.  The actual size refers to the final dimensions after this process. So a common 2"x4" is really about 1.5" x 3.5." This is important since the actual dimensions are needed when choosing shelf brackets and planning a project. 

Here are a few charts to make this easy:

Lumber Dimensions: Nominal and Actual Sizes

Standard Lumber: 1 by board

NOMINAL SIZE (INCHES)

ACTUAL SIZE (INCHES)

1 x 2

3/4 x 1 1/2

1 x 3

3/4 x 2 1/2

1 x 4

3/4 x 3 1/2

1 x 6

3/4 x 5 1/2

1 x 8

3/4 x 7 1/4

1 x 10

3/4 x 9 1/4

1 x 12

3/4 x 11 1/4

 

Standard Lumber: 2 by board

 

NOMINAL SIZE (INCHES)

ACTUAL SIZE (INCHES)

2 x 2

1 1/2 x 1 1/2

2 x 3

1 1/2 x 2 1/2

2 x 4

1 1/2 x 3 1/2

2 x 6

1 1/2 x 5 1/2

2 x 8

1 1/2 x 7 1/4

2 x 10

1 1/2 x 9 1/4

2 x 12

1 1/2 x 11 1/4

 

 

metal shelf bracket

 

Remember, these guidelines only apply to dimensional, common lumber. Custom shelf boards or those pre-made (such as those sold online at West Elm, Amazon, World Market, etc. will display final measurements).  Hopefully this provides some clarity in using dimensional lumber for making shelves! For more information, check out our How to Make Shelving Guide with step by step instructions in choosing the correct brackets for your project.