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Thank you for providing this text. I don't know why HN even permits the linking of pdf's if they can be a vector for arbitrary execution and privilege escalati

• walterbell 4y ago
  The text quoted above is a short essay on the same topic from Harvard. Here's the Forest Service PDF summary: > Lumber size standards came into being almost a century ago to meet the need for a common understanding between the mill and markets that were separated by increasing distances of rail or water transportation. Early concepts called for rough lumber to be of full nominal size, often in the dry condition. After World War I, the increasing demand for construction lumber led to the first national size standard in 1924. This was revised in 1926, 1928, 1939, and 1953, while still another revision is proposed for adoption in 1964. > Demand for lumber in World War II led to the shipment and use of large quantities of lumber dressed green to standard sizes. That use has continued to the present time, while experience has accumulated on how to deal with the seasoning and shrinkage of lumber in place in a structure. The proposed new lumber standard recognizes both green and dry lumber, requiring the former to be of larger size so that both will be of the same size when they reach the same moisture content in use. > Economic pressures among the regional areas of lumber production have resulted in a decrease of standard lumber sizes over the period covered by this history.