(John Ruth's soapbox rant removed)
I also like in a domicile of pre Great War vintage, with principal construction
involving material of actual rather than nominal size. When I purchased (or,
more accurately, convinced the bank to purchase for me) the structure, there
were a fair number of joists with shear splits, spacing from 19.2" to 24" on
center, a good bit of twist in various structural elements, and a couple hard
hurricanes and winter storms (100+MPH winds the week after I closed, 18-24" of
snow on the roof that winter, and so on every year since) to prove to overall
soundness despite the structural shortcomings.
I have repaired a number of failings, most of which were due to prior owners,
such as where a section of ledger was cut out leaving a big part of the first
floor joists supported only by a single toe-nail each. This is how I learned
that you can get, in theory, Teco (or equiv) hangers in widths for a variety of
lumber sizes for just such a contingency. Of course, practice and theory don't
always match up, so I bent and/or welded up my own for some locations.
The nominal sizing goes back to WWII or before, based on some of the lumber I
have found and some of the references I have on the shelf, including pre-WWII
structural texts that give the nominal sizes for BOM, and actual sizes for
calculations. A data point in hand is 1-5/8 thick 2X lumber used for work done
in 1942. It came this way from the yard, as the mill stencil is visible on a few
pieces and has the stylishly rounded corners that came into vogue in the early
20th.

As to the lawsuit in question, I haven't read it, but there was one a few years
ago (less than 25, at least, as I was already in NJ) that the lumber was
undersized versus the standard. Every piece was at the bottom limit of the
acceptable range, when the intent of the standard was a distribution over the
range. If building so close to the spec that the few percent loss there is an
issue, things are very wrong, but I was absolutely in sympathy. Remember when
3/4 ply became 23/32 ply? and the actual size today is likely to 22/23, the
bottom of the range both then and now, IIRC. *** This message was sent from a
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