Nominal Lumber Size Dimensions and Conversion Chart

In a way, it has always disturbed me that the lumber industry can’t come up with a simple format for measuring their product. Why can’t a 2×4 be just that, 2″x4″? Instead I have to clutter my head with needless math problems. Let’s see, when I hold two 2x4s together they are actually… 3″ x 3.5″ …or is it 3.5″ x 3.5″?
Nominal vs. Actual
The label put on the lumber you buy is called the “nominal” lumber size. The actual size is always a little bit smaller. Nominal refers to the dimension the lumber was sawn. When a 2×4 is cut out of a log it is 2″x4″. After the board is dried and planed it becomes its actual size of 1 1/2″x3 1/2″.
If your memory is like mine, and you need a little help remembering the actual dimensions of the lumber you’ll need for your next project, then here is a quick conversion chart:
Nominal Actual
5/4″ 1 1/8″
1″ 3/4″
2″ 1 1/2″
3″ 2 1/2″
4″ 3 1/2″
6″ 5 1/2″
8″ 7 1/4″
10″ 9 1/4″
12 ” 11 1/4″
*Tip – Sometimes you’ll need a filler to get sections where boards meet to be of equal size. For example, the header to a door or window is usually made with two boards set together and resting on an upright stud. The upright stud will be 3 1/2 inches wide, but the two header boards (each 1 1/2 inches wide) are only 3 inches when put together. So, the solution is to cut a piece of 1/2″ plywood to equal size, and sandwich it between the two header boards.
Latest News
-
5 Questions to Ask Before Buying a Shipping Container
Shipping containers are becoming more widely utilized,...
- Posted July 3, 2019
- 0
-
Useful Tips for a Greener Office
For most of us, work is where...
- Posted September 14, 2018
- 0
-
Simple Ways to Lower Home Cooling Costs
Spring is near in sight, and that...
- Posted March 2, 2017
- 0
-
DIY Disaster – Oversized Load
We focus a lot on “How to”...
- Posted September 8, 2014
- 0
-
Best Step Ladder – You Choose
Are you in the market for a...
- Posted August 14, 2011
- 2
-
Safe Room Construction
A couple years ago, safe rooms (a.k.a....
- Posted May 30, 2011
- 7
-
How to Make a Center Line Jig
In this video tip I teach you...
- Posted January 27, 2011
- 1
Free Delivery
Join Us On Facebook
-
5 Questions to Ask Before Buying a Shipping Container Shipping containers are becoming more widely...
- July 3, 2019
- 0
-
Useful Tips for a Greener Office For most of us, work is...
- September 14, 2018
- 0
-
Simple Ways to Lower Home Cooling Costs Spring is near in sight, and...
- March 2, 2017
- 0
-
DIY Disaster – Oversized Load We focus a lot on “How...
- September 8, 2014
- 0
-
How to Cut a Laminate – Formica Countertop Plastic laminate countertops are economical, durable,...
- January 28, 2010
- 31
-
Safe Room Construction A couple years ago, safe rooms...
- May 30, 2011
- 7
-
Nominal Lumber Size Dimensions and Conversion Chart In a way, it has always...
- June 11, 2010
- 7
-
Repair and Patch Drywall | How to Fix a Hole in Sheetrock Did some of the guests get...
- December 28, 2009
- 5
7 Comments