Carpenter Markings

While the contractors had many of the walls ripped down to the original studs, I noticed something that perplexed, then excited me…roman numerals transcribed on the beams where joints met.

After doing some research, I found out that these are actually carpenter’s marks.  The purpose of the markings was to help the builder (who may not have been the initial architect or carpenter) assemble the joists the way they were intended to be assembled.  Before 20th century technology allowed for more consistent pre-fabrication through the use of more advanced tools, standard measurements, and precise methods of joining wood, all of the beams or “sticks” for the house had to be hand-cut, meaning each joint consisted of two puzzle pieces that fit only with each other (how romantic!).


The marks on the beams correspond with the joist where they were supposed to be matched.   Often, the numerals do not “match” in the sense that all of the beams are marked “VII” for example.  Instead, they are marked directionally.  Two beams that meet at a joint would be labeled mirror image from each other, such that a beam marked “XII” would match with “IIX”.  To complicate things, the cross beam might be labeled VI (as below), the top beam is marked IV, and the bottom beam is marked VI.  The idea is that if you split the numerals from the cross beam (VI), the bottom beam corresponds with the “V” and the top beam corresponds with the “I”. The two beams, top and bottom, marry at the “V”.  There just happens to be a beam in between, marked to specify which beams belong above and below it.

So it is no surprise why we moved toward carpentry standards!  Another point worth noting are the “tree nails” or wood pegs holding the beams in place.  These too would have needed to be chiseled and custom fit, since nails were not common in frame construction until the late 19th century.  Yikes!

This was a great find, and I’m so lucky the bathroom wall was molded so badly it resulted in the need to strip the plaster!