My thanks to Jim Derby for calling my attention to comments on this thread. I responded personally to Ken Hume, but at his urging, I'm also posting that response here:
Ken,
First, you should know that when I started in 1974, I hadn't met Jack yet and his first book didn't come out until 1984. My first book was written in 1978.
Second, I've always been a little dubious of the merits of trying to interpret forms of timberframing in history as if those guys were any different than you and I. They learned, adapted and improved over the course of their lives much as you and I have, and will. Like us, they were only prisoners to learned procedure and habit, not to rules that had to be adhered to, other than their mental ties to the conventional thinking of the time. As I look around at the residential building technology in today's world, I think that most of the conventional systems are inadequate or wrong, simply because there is apparently more ties to habits than there is creativity in adaptation and learning. So why would it have been any different 200 years ago? There were trends, but those trends were not binding rules and were not necessarily the best that could be done. I therefore do not assume the best of systems was always that which was most widely practiced.
In any event, when I was in my early years of timberframing, I wasn't looking to replicate the most historically accurate form of framing (what would that be?) or the most dominant (where?), but I was trying to learn from the past masters about methodologies that might best address the materials, tools and economics of what I hoped would become a thoroughly modern form of timberframing, based on our particular situation.
What you call a connecting girt (interrupted wall plate?) form of framing fit the bill. I found several barns in the Hillsborough, Henniker, NH area that were framed that way. What I saw immediately is that it would solve my short timber problem, eliminate the need to make scarf joints (time consuming, expensive) and allow the possibility that I could pre-cut wall girts and roof purlins to the same dimension, which greatly increased the efficiency of making the frame. It also created a situation where the posts could be connected directly to the principle rafters, which meant there would be no shrinkage in the height of the building. Since we used green oak and pine primarily, this shrinkage issue was significant. I didn't think good quality buildings could tolerate 1/2" to 1" of shrinkage and I still don't. Therefore, the reason I adapted this system was for efficiency (cost) and building quality.
Since those early years, we have continued to adapt, learn and improve and what we're doing in our 4th decade bares scant resemblance to the work we did in our 1st decade. I also have tried to document the changes and improvements in my series of books. As we have developed through the years, we have been able to learn from every period in history and from all parts of the world. Our work has also been tremendously influenced by modern engineering and contemporary foreign influences in our shop, including numerous timberframers from Japan, Germany and France. Of course, like all timberframers in the TFG, we are learning a lot from our contemporary colleagues as well. Sometimes, we've made frames from local materials that couldn't be longer than 20 ft. and sometimes we've had large quantities of timbers available up to 80 ft. All of these things have affected our timberframe designs, but probably nothing has had more influence than the evolution of the architecture of our buildings. For obvious reasons, frame design and building design are intertwined and it is our hope that we are defining an architecture of timberframe buildings that will endure centuries into the future. In the long run, the functionality and beauty of the building will have a far greater impact on perceived quality of the timberframe than whether it has continuous or interrupted plates, or any plates at all, for that matter.
