Postwar housing required even more lumber. In the meantime, demand for ammunition pallets and crates during World War II created lumber shortages. However, disagreement about specific considerations persisted for decades. In April 1919, attendees of the first American Lumber Congress called for size and terminology standardization. As retailers clamored for more regulated measurements and standards, trade associations were formed. Lumberyards demanded uniformity so that builders could compare cost and quality. And the differences in how lumber was sized, surfaced, and dried became apparent in the lumberyard, where a medley of species in various dimensions claimed to be 2x4s. This development coincided with the mid-19th-century evolution of building framing-from timber-braced to light-stick balloon and its derivatives-which progressively utilized greater amounts of “small dimension stock,” like 2x4s. The same steam engine technology that powered the railroad, for instance, enabled the newly invented circular saw to achieve faster, continuous cuts in the sawmill. Other factors also drove the market toward smaller sizes. The 1909 textbook Construction Superintendence acknowledged that lumber classification was “a matter of judgment” and cited lumber inspection rules for three areas that they considered to be major centers: Saginaw (west), Maine (east), and Baltimore (south).

And they influenced manufacturers’ associations to prescribe commercially advantageous sizing rules. They produced optimal finished sizes of preferred species by kiln drying to control moisture content. Lumbermen favored thinner, lighter sizes for longer hauls. Thus, the physiological variables of density and moisture began to have an outsized impact on forestry economics. According to the US Department of Agriculture’s “History of Yard Lumber Size Standards,” shipping charges, determined by distance traveled and weight, doubled the cost of lumber.

The phenological and physiological variability among species was influencing purchase economics.Īt the turn of the 20th century, lumber was commonly sold FOB-free on board, with the purchaser responsible for shipping-as it is today. Buyers needed convincing to purchase lumber from unfamiliar species, and hence marketing focused on differentiating attributes such as ease of use, workability, strength, load capacity, and grain movement. For example, southern pine forests called “pineries”-consisting of shortleaf pine, slash pine, longleaf pine, loblolly pine, and other less common species (collectively known as southern yellow pine, SYP)-were pitted against western Douglas fir, western hemlock, and spruce forests. A new phenomenon was born: species intermingling at market.Ĭompetition occurred among regions, or more fundamentally, among species. Lumbermen purchased vast areas of forestland in the north, south, and west of the country. With the advent of the railroad in the 19th century, transportation options and demand for wood increased. Rivers, canals, and lakes, made Bangor, Albany, and Chicago wholesale timber capitals. Trees were floated out of their watershed, breaking the link between lumberman and carpenter. Prime forestland-determined by tree size, species type (originally and exclusively white pine), and access to transportation-was changing. Supply and demand concentrated around the major port cities of New York, Baltimore, Boston, and Philadelphia. As trees were harvested, however, human ecology transformed forestland into farmland with landscapes deforested for many generations to come.Īvailable forestland, therefore, moved toward the hinterlands as nearby areas were cut over. North American forests seemed an unlimited resource for almost everything.

Sizing tolerances varied, thus leaving final measurements to site construction. Before industrialized wood production, which began around 1870, trees were felled, skidded, sized, and made to order for carpenters. To accurately reflect its dimensions, the 2x4 should be renamed the 1½ x 3½.Īn obsessive concern for material efficiency in the United States, the dominant global user of light-stick framing (also known as 2x4 stud construction), has driven the use of the 2x4 and its resultant commodity homogenization. The naming of this building material is the result of compromise between forestry technology, species’ properties, forest composition, transportation efficiency, construction speed, and price competition. The ubiquitous lumber product known as the 2x4 does not, in fact, measure two inches thick by four inches wide.

4x4 actual size