I had a great education today. Mike was working on a project and the number of pieces of lumber he needed varied from what my tiny little brain calculated. Of course, I was looking over his shoulder and had to put in my two cents. He then told me the truth about lumber. It lies. That’s true. Lumber says it’s bigger than it really is! (Does this remind you of any men you know?) He said there are really two different measurements for lumber. The nominal measurement, what it’s called, and the real measurement.
I didn’t believe Mike so I had to look it up for myself. Sure enough, he was right. So why in the name of all that is sane, would an entire industry screw with your mind like that? There is a very logical reason for this.
The United States was inviting to the early settlers because of its vast resources, especially the timber. In 1608, the settlers of Jamestown, VA constructed the first sawmill of the nation, which cut the lumber to order for each request. Mills grew throughout the nation in the 1700’s and 1800’s. By the late 19th century, the urbanization of the East Coast led to dependency on the wood cut further west and shipped back to the urban areas. Standardization of the dimensions of lumber became mandatory after WWI when construction increased dramatically in the cities. Enterprising saw mills cut the rough lumber edges for uniform dimensions, which allowed shippers to produce the lumber on site already cut and fill orders quicker. The surfacing at the mill, allowed for cheaper shipping costs. In 1924, sizes the United States standardized the sizes for dried boards.
Before WWII, even though there was some variance because of surfacing, they cut the size of lumber after it dried and there was no shrinkage. WWII increased the need for lumber even more and soon green dressed lumber left the mill and went to the building site. As the lumber dried, it shrank and now the standard sizes were slightly smaller. The surfacing at the mill and the shrinkage made the real measure different from the nominal or named size.
The measurements of boards are by their width and height. They list the length separately. The nominal size of a board is the name of the board. For instance, 2X4 might be the name of the board but the real measurement is 1 3/4 inches by 3 1/2, which allows for the shrinkage of the wood. When the nominal measurement is 1 inch or less, you subtract 1/4 inch to get the real measurement. If it’s 2 inches to 6 inches, take off 1/2 inch. Those boards that have a nominal height or width of 8 inches or more you subtract 3/4 inch for the true measurement. A 2X8 is really 1 1/2 by 7 1/4.
You get the actual length when you purchase lumber, rather than a nominal length. Lumber length sometimes comes in one foot length differences but it varies by the grading rules for the type of the wood. Most softwood lumber, the kind used for construction and found in the home remodeling stores, varies by 2 foot differences. The grading rules differentiate between the quality of boards and their uses. Lower grades are for common construction and better quality grades for finish work or work that’s painted.
Standard lengths of hardwood lumber is cut to the lengths of 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, and 16 feet. Hardwood doesn’t have standard width and height but do have minimums for specific grades. If the lumber is first or second grade, then the width is 6 inches. Select grade is 4 inches and number 1, 2, 3A, 3B and common is 3 inches. The thickness varies by the number of surfaced sides.
Lumber is either finished or rough. Rough lumber isn’t finished into boards, but sent to factories that create furniture or other items made of wood. Projects that use boards, such as home construction, use finished lumber. Finished lumber comes in standard sizes that make it easier to purchase and use.
We have two date nights a week. One of them is grocery shopping on the night of the senior discount, Tuesday and the other is tonight! We’re going shopping for supplies for his job tomorrow. Yes, it’s a sad social life, but now I get to check out the lumber myself. I’m taking a tape measure, just to keep them honest.