Much as a 12oz steak won’t weigh exactly twelve ounces when served to you after cooking them a 2x4 piece of wood was nominally that measurement prior to the kiln drying process.
It’s more that they used to be shipped 2x4 unfinished, and would be planed smooth on site. Once the equipment and distribution was able to do the planing before it got to the customer, they had so much established practice that the installed timber would be smaller, they had to keep to what people were used to.
2” x 4” construction timber is 1.5” x 3.5” because of industrialisation (not shrinkflation)
Because of universe expansion. (I guess industrialisation also works)
Much as a 12oz steak won’t weigh exactly twelve ounces when served to you after cooking them a 2x4 piece of wood was nominally that measurement prior to the kiln drying process.
It’s more that they used to be shipped 2x4 unfinished, and would be planed smooth on site. Once the equipment and distribution was able to do the planing before it got to the customer, they had so much established practice that the installed timber would be smaller, they had to keep to what people were used to.
xkcd?