As you may know, 2x4s are not actually 2 inches by 4 inches, as you might otherwise expect. The story is that the board begins as a true 2x4, but the drying process and the planing of the board reduce it to a finished size of 1.5x3.5 inches. That wasn’t always the case, however. At one time, if you paid for a 2x4, giving you something less would have been considered unethical or illegal. Today, there is a standard for finished lumber sizes but the standard doesn’t match the name that is attached to it.
@Ken Anderson Our old farmhouse in MO, thought to be close to 100 years old, had full-nominal size timbers in it. We ripped open the ceiling in one room, and the rafters were actually a full 2 inches by 8 inches! We failed to find any squirrels or rats, but the night-time chewing and scrounging sounds continued. Frank
I hate the word "nominal". That means when you buy a 9'x12' tarp, it's only a "nominal" size, usually 8 1/2' x 11 1/2'. I'd like to get to the checkout and hand them $19.25, instead of $20. After all, if a 9x12 tarp sells for $20, shouldn't a "nominal" size sell for a "nominal" price? Somehow, I doubt Walmart would see it that way. Listen, when I get elected God, there are going to be some changes made! First thing to go is "nominal"...….
@Mary Robi I shan't grant a like unless we can clarify your interpretation of "nominal" vs my own. I may be in the wrong here, admittedly. "Approximate or roughcut dimension by which a material is generally called or sold in trade, but which differs from the actual dimension. In lumber trade, for example, a finished (dressed) 'two by four' piece is less than 2 inches thick and less than 4 inches wide. Also called nominal size. See: http://www.businessdictionary.com/definition/nominal-dimension.html See, my understanding of the usage in terms of everyday trade is as I imagined it to be. My use of the word is thus quite different than the Webster classical definition of "too small to be of significance".
Cambridge Academic Content Dictionary in name or thought, but not in reality: He’s the nominal head of the university. synonym: false
@Ken Anderson Very true. Yet, I thought his post was acceptable as a comparison tool for the questions at hand. While I am not a dedicated supporter of @Joe Riley , it would seem his post was justified, but WTH, you run your forum, and I get few opportunities to scrap with you, though such chances mean little. Plus, I full-well understand everybody's human, and even Admin has a rough day following a partly sleepless night every so often. Might I sign off, now? Frank
Illinois man sues Home Depot because two-by-four wasn't two by four " Everybody knows a two-by-four isn’t two inches by four inches." "In fact, federal-government standards define a two-by-four as measuring 1.5 inches by 3.5 inches. But that hasn’t stopped Mikhail Abramov, of Illinois, from filing what he hopes will certified as a class-action lawsuit against Home Deport for selling undersized lumber." "Abramov’s suit, filed in federal court in Illinois in April, says that he went to a Home Depot in Palatine, Illinois, in December to buy a four-by-four for a “small home improvement project.” When he got home, the suit says, he found out that the wood was only 3.5 inches by 3.5 inches." "The suit says that Abramov was deceived by Home Depot and would have paid less had he known he was getting less lumber. It says that Home Depot sells “lumber products that were falsely advertised and labeled as having product dimensions that were not the actual dimensions of the products sold” and that “unbeknownst to consumers, the product dimensions advertised by [the store] are not the actual dimensions of the products being advertised.” “In fact,” the suit says, Home Depot’s “dimensional lumber products all have materially smaller dimensions than those represented in its advertisements and product labeling.”
I have always believed the listings of wood dimensions to be true. Some good points in the lawsuit. This is probably why my projects always come up shorter than I calculated and I have to figure out how to make it fit, .
Why aren’t two-by-fours two inches by four inches? "When sawmill operators adjust the “set-off” on their equipment — that is, the amount the log is advanced after each pass through the blade — they must allow for the kerf (or width) of the blade plus shrinkage. " "In the 19th century, they lacked an accurate way to gauge moisture content. So they made the set-off a little wider than the nominal size, knowing the true size of the seasoned lumber would probably be a little less. The difference between nominal and true size was known as “scant” allowance."
A person suing a Home Depot or Lowe’s for shorting him on the lumber sizes would be hard pressed to make it stick. Unlike going to a normal lumber yard, the mega DIY stores not only list what their wood products are e.g. 2x4, but on the same card or another sticker it will also give the actual measurements in parenthesis. And, although I have not calculated it in recent years, I do believe the amount of “board feet” that is charged for will be based on the actual finished measurements of the wood. Now, there is some dispute but some say that one of the reasons for the reduction is the same as the reason concrete blocks aren’t their “true” sizes. With concrete block and brick, the difference is because of the proposed mortar measurements in between the blocks. 3/8” of mortar Plus the real block size brings the overall measurements up to an even 8”x 16”. Now, although some say that it is the same reasoning for studs, at the present time of drywall use, it’s not. Maybe when 3/8” lathe strips and an 1’8” of plaster were used but in today’s construction practices, it just ain’t so. It might be of some interest though, metal studs are the same sizes as their wood stud counterparts.