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HE BEGINNINGS OF QUALITY TIMBER FRAMING ARE LOST IN PRE-HISTORY, but a reasonable surmise is that simple frames could have been made by supporting beams on columns which had a natural fork at the top, the kind of thing that we boys of the 1950s saw in Boy Scout manuals or Straight Arrow cards stuffed as premiums in Shredded Wheat boxes. (Gee, I wish I still had those!) Once a horizontal timber is supported by the verticals, considerations such as stability and strength enter the equation. Early builders would have recognized the inherent strength of the triangle. The value of the pitched roof would have been recognized soon thereafter, and timber-frame structures were off and running. Refinements in both kind and degree would have evolved by trial and error, a kind of structural evolution, with failed tests being dropped by the wayside and successes passed on through the generations.
Early humankind did not have metal tools and fasteners, but they did have excellent stone tools, and quality timber framing could and would have evolved without metal. Archaeological evidence at Neolithic sites — post holes primarily, as little wood has survived — show the shapes of houses in Europe 5,000 years ago, and suggest the kind of rafter systems that would have been required to roof the structures. Some were quite magnificent, like the huge round wooden temple at Stanton Drew in Somerset, England, which predates the megalithic stone circle at the same site. This earlier structure, discovered by the use of magnetometers in the late 1990s, would have had a diameter of 312 feet (95 meters), and was composed of about 400 very large oak posts. Experts disagree as to whether or not it was ever roofed, but the radial location of posts strongly suggests a radial rafter system. A project of this scale, at that time of much lower population than today, was an infinitely more impressive feat than, say, the building of Londons Millennium Dome or a modem American indoor sports arena.
How long these buildings lasted we shall never know. We know now that longevity of a wooden structure is closely tied to the quality of the foundation and the roof. The primary cause of wood rot is the propagation of fungi, which require air, water, and nutrients. If a constant damp condition can be avoided, wooden buildings will last an awfully long time. You need “good shoes and a good hat,” said the old-time builders, referring to the foundation and roof. I would add, “and good ventilation.”
As a youth of 19, visiting the Alpine village of Wengen, Switzerland in 1967,1 was asked to guess the age of the large chalet where I stayed. The building looked new, but I dutifully guessed an age of twenty years. I was shocked to learn that the home was 500 years old. The alpine climate, the quality of construction, and Swiss maintenance combined to preserve the building in an “as-new” state.
An example of this craftsmanship is worth relating. Wood swells at humid times, and shrinks when the air is dry. There’s not a great deal we can do about it. Nailed-down hardwood floors can buckle when they take on moisture, for example. In some Swiss houses of centuries past, the floorboards were not nailed down. Rather the center plank (or more than one) in the floor were tapered, with their ends actually sticking out of the building, accessible to a wooden mallet. In the winter, when conditions were dry, driving the wedge-shaped boards in from one end tightened the floor. During humid times, the opposite ends of the boards could be struck with a mallet to slightly loosen the floor, thus preventing buckling. And just think of what an easy matter it would be to replace a board.
