The Conservation of Historic Timber Framed Structures

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The Conservation of Historic Timber Framed Structures

Chapter 01. The History of Timber Frames/Roofs

Post-and-beam construction, or timber framing, is steeped in a history that extends back over two thousand years. It developed gradually over the years and the 10th century witnessed what is believed to be the first completely self-supporting timber frame system, eliminating the need to sink poles into the ground where they were exposed to mildew and rot. From this new system evolved a look that was to forever dominate domestic architecture in style, design and practicality. Spanning the globe, timber frame structures evolved as Japanese temples, English manor homes and American farms (Charles, 2006: 12).

Early post-and-beam structures required arduous work involving the use of axes, adzes, chisels and a host of other tools relying solely on muscle power. Despite the toil necessary in the construction of post-and-beam buildings, their inherent advantages made such efforts worthwhile. Unlike log homes that were completely made of wood, timber frame walls allowed in-fills of mud, brick and other materials that could then be plastered over (Ashurst & Ashurst, 1988: 69). This gave a much lighter appearance and cut down on the use of timber where it was scarce. Time passed and post-and-beam construction, with its structural superiority over other methods, abounded.

Though practical, post-and-beam homes remained out of reach for much of the world population, as they were often expensive and time-consuming to build. This all changed with the discovery of the New World. Over time, a uniquely American style took shape, introducing innovations that reduced timber usage and emphasized simplicity and functionality, making post-and-beam structures affordable. Another advancement of the day was the invention of large pre-designed frame units, which a community could fit together and raise in a day. Anyone who has ever witnessed an Amish barn rising will attest to the benefits of this team approach to erecting timber frames and while construction crews have replaced the community's role in many areas, the efficiency and practices handed down remain inviolate.

As we enter the 21st Century, the most important advancements in timber frame construction have been the introduction of energy efficiency. Today's post-and-beam structures often feature large southern windows for passive solar heating, easily circulating air and insulated roof and wall panels (SIP panels) that form an airtight sheath (Bell, 1997: 96). This, along with a whole host of other eco-conscious evolvements, have resulted in a revitalization of this age-old construction practice and assures that timber framing will continue its dominance in practical, forward-thinking construction for centuries to come.

The Roots of Timber Framing

Mortise and tenon joinery can be traced back to furniture hand-crafted in Egypt 2000 years ago. How joinery came to be used in building construction is not known, but there is ample proof that builders in all of the temperate regions of the world relied on some form of timber frame construction. In China and Japan, timber framing was the most common method of wood construction until the 20th ...