Saturday, October 3, 2009
Old fashioned carpentry
Photos: Ryan makes a notch for a 6 by 8 hemlock beam, which will hold up the hay floor of our barn.
This post mirrored from our barn blog.
The exterior walls of our barn are "stick-built," meaning they are built with relatively thin sticks of lumber, two by four inch by eight foot studs, or "2 by 4 by 8's," or just "studs."
Wishing to build both a sturdy and a locally-sourced building, we employed fully two inch by four inch, locally produced, "rough cut" hemlock lumber of high quality, which we bought in quantity from Gerald Fowler's lumber mill in Thorndike, Maine.
I say "fully" because most lumber that carpenters and contractors use for building is only nominally 2 by 4 inches. Mainstream commercial lumberyards for generations have sold only kiln-dried, planed, stamped 2 by 4 studs. The "stamp" is the manufacturer's quality assurance stamp, and while most carpenters know it means very little, most insurance companies wish you to build with this material. The reason is not because it's the best lumber to use for any particular purpose. It's instead authorized for use because this kind of lumber, stamped by a reputable and large lumber company, carries with it the implied promise that, if the carpenter or contractor uses this lumber, uses it correctly, following standard systems taught in trade school and written in carpenter's manuals, then if the building then falls down, causing a loss for the insurance company, the lumber company will be available to be sued, as well as the contractor, and any sub-contractors, to make up the insurance company's loss.
The lumber companies, contractors, and all but the flakiest of subs, carry bonding and insurance too, just in case they are sued.
Kiln dried lumber, however, is not two by four inches but instead planed down to an actual dimension of one-and-a-half by three-and-a-half inches. This dimension was not chosen for ease of calculation. It was chosen because this was what you got when you planed down a rough two by four. These days, with low kerf band saws and high speed planing knives, you'd get a larger stud by just planing down a rough two-by four, but the one point five by three point five inch size is kept because the savings from the new equipment has been absorbed as extra profit to the lumber company, not passed on as stronger lumber to the customer.
Kiln dried or KD or, phonetically, kay-dee lumber is brittle, generally cut from spruce or douglas fir, cracks easily, warps spectacularly in the wrong circumstances, rots well, and has less than half the strength of air-dried rough cut lumber if hemlock is the species used. Experienced carpenters in Maine, where this conifer is abundant, keep hemlock lumber around and use it for bracing and other jobs where superior strength is needed.
They also use it to build their own buildings, especially outbuildings, where wallboard is not used. Hemlock has the additional benefit of being rot-resistant.
Kiln-dried is for the customer's barn, not the contractor's.
So why would anyone use kiln-dried lumber for an outbuilding?
Because the insurance company made them do so.
This is one of those cases where the decline in lumber quality and concurrent common sense is a symptom or knock-on effect of a primary shift in values in society as a whole,
Long ago, lumber companies began kiln-drying and planing lumber to make it easier to get smooth finishes on walls if dry wall and other wallboard products were to be used. Before drywall there was lathe-and-plaster finish which could accommodate the irregularities of rough cut lumber. My own farmhouse, 109 years old this summer, is rough cut hemlock, and originally had lathe-and-plaster walls. But drywall saves time and produces a smoother if not superior finish, and so planed lumber, and wallboard, were needed to "knock out" the cheap family housing that began to be the norm after Levittown and other motor suburbs, eventually with their attendant shopping malls and "box stores," came to replace the historic pattern of American cities, beginning in the 1950s.
Most American families benefited from this cheaper housing supply and the overall price of housing fell, allowing middle-class values of home ownership to be achieved lower on the pay scale than previously possible. It was also in this era that the dependent, commercial, middle class suburban house began to replace the independent, subsistence and market-producing, rural homestead or farm as the American ideal housing format, the dream that most would strive for.
In fact, since the 1950s there has been a substantial net loss in farm and homestead ownership, and a corresponding commercialization and intensification of agriculture.
And so went the Jeffersonian dream, taking the rough cut 2 by 4 with it, superior strength notwithstanding. Now you can only buy them from small private lumber mills.
Actually, Jefferson, who wasn't a carpenter but knew a fair amount about building and planning, probably would have thought of even rough cut, stick-built, lathe-and-plaster finished housing as cheap and nasty. In Jefferson's time, if you built to last, you used stone, brick, and post-and-beam construction.
The walls of our barn are thus somewhat anachronistic, and employ a building technique, using rough cut sticks, abandoned by the mainstream some 40-50-60 years ago. The interior frame of our barn, which will be held up by massive, cross-braced hemlock posts and beams, will use a technique a hundred or two hundred years yet more anachronistic. Post and beam technique, in English-speaking society, dates back to the Anglo-Saxon settlement of England, or before, to the Iron and Bronze Age Celts. The technique was well known to the Romans and Greeks, and, where timber was available, used throughout the biblical world of the ancient Hebrews and Egyptians. Carpenters in the time of Ptolemy or Aristotle knew how to make a cross-brace that fit. Jesus, an Israeli carpenter by nationality and trade, would have used these techniques. His cross certainly used them. David's palace, and the first, second and third temples, would all have had post and beam roofs, even if the walls were of Jerusalem limestone.
The oldest European-settlement buildings in America are post and beam.
Many can be studied to this day, if you are interested in how buildings, and societies, are built.
My own particular favorite, in which the carpentry, and social construction, can still be observed well to this day, is Third Haven Quaker Meeting House in Easton, Maryland. But I'm a Quaker, and so biased. Third Haven used "green" or fresh-cut American white oak, Quercus alba. In Britain, where the Third Haven Quakers came from, we would have used the English oak, Quercus robar.
Interestingly, alba, in gaelicized Roman, also is Albion, perfidious or not, and where the Third Haven Quakers, and me, were from.
Third Haven was the third haven they had found from religious persecution, as they tried to build a better society.
It was not a metaphor. They were kicked out of the previous two.
The Easton Quakers still meet there every Sunday, or First Day, in summer. These days most that are not retired are commuters and many work in Washington DC for the government.
As for our class, we're just beginning to take our inquiry into the building of a building a little deeper, inquiring further into what the design and execution of a building might teach us about the building of a society.
At 8am, the time for our class, students are tired, and much as Trey, one of last year's students, described in his post here, participation in that debate seems too much for most. Most would rather just build. Building a building is more concrete, and possibly more fun.
But there are hopeful signs that a few are willing to begin to think about what kind of society they are being trained to lead, and how to make sure it is sturdy-built and will serve, or even serve better, for their lifetimes at least.