However, as my intern proved, not everyone knows that there is a difference between nominal and actual lumber dimensions. Yes, that lawsuit was a little ridiculous. Now they must also label their products using descriptive words like “inch” and “feet” instead of standard industry symbols like “ or ‘. They were ordered to pay a $1.6 million dollar settlement in California and were required to label their lumber with both nominal and actual dimensions. The Marin County, California Department of Weights and Measures took civil action against Lowe’s because they unlawfully advertised their lumber according to the nominal dimensions. According to their website, the purpose of these standards is to: 'Establish nationally recognized requirements for products and to provide all concerned interests with a basis for common understanding of the characteristics of a product.'Ĭonsidering all of these facts, the entire building industry was scratching its head a few years ago when Lowe’s was sued over its lumber labeling policy. Lumber dimensions in widths and thickness are 1/2-inch less than the size. Lumber sold in the United States in governed by the National Institute of Standards and Technology. Knowing lumber sizes in advance helps reduce waste. Yes, it might appear as if lumber mills are selling you one thing but giving you another - but it’s actually not like that at all. While comparing nominal and actual lumber dimensions, you might be thinking that this is another case of companies trying to pull one over on consumers. Here are the basic rules to keep in mind: This fact makes no difference in the building industry because architects and contractors are (hopefully) aware of this discrepancy.īelow is our lumber dimensions chart to help you quickly find the actual size: Īs you can see from the lumber dimensions chart above, there is a bigger difference between the nominal and actual size of larger lumber pieces. Most lumber is described using nominal dimensions but is actually smaller in reality. The actual dimensions of a 2x4 are 1.5 inches by 3.5 inches or 38mm by 89mm.

During this finishing process the 2x4 shrinks. However, it must be dried and planed before it can be sold for purchase. In lumber measurements this denotes a rather thick and heavy board, 2 by 4 (2 inches x 4 inches) (also 2x4) commonly used. When the board is first rough sawn from the log, it is a true 2x4, but the drying process and. When the board is first rough sawn from the log, it is a true 2x4, but the drying process. When a 2x4 is cut from a large piece of lumber it is actually around 2 inches by 4 inches in size. 2x4s are not actually 2 inches by 4 inches. 2x4s are not actually 2 inches by 4 inches. The wood you find at your local home improvement store or lumber yard is described in nominal dimensions. Unless you’ve worked as a carpenter, you might be surprised to learn that a 2x4 is not actually 2 inches by 4 inches. She quickly replied “2 inches by 4 inches - duh” and went back to work. The other day I asked my intern a simple question: “what is the actual size of a 2x4?”

Actual dimensions of a 2x4