14 C O N T E X T 1 3 4 : M A Y 2 0 1 4 decision-making process, is to deny the reality of almost every conservation project. It is not uncommon for a building to remain unrepaired and vulnerable, if not in a state of accelerating decline, because the extent of repairs deemed necessary, and the costs of the methods and materials specified, is too high. Until the beginning of the conservation movement in the late 19th century, the principal criterion in choosing a method of repair was cost. As a result, repairs tended to be simple and pragmatic, involving the minimum work and disruption necessary to return the building or structure to a condition fit for its purpose. This might involve, among other things, the addition of metal brackets and straps, the insertion of additional timber elements, or the replacement and/or repair of the existing timbers. A survey of a typical Herefordshire farm complex comprising of farmhouse and ancillary buildings, mostly timber-framed and ranging in date from the 14th to the 19th century, provides a snapshot of historic approaches. Excluding substantial alterations and rebuilds, the identifiable repairs included 38 metal straps, brackets steel cables and suchlike, 23 new or re-used timber elements, and two repairs where decayed timber had been cut out and replaced with new sections of timber jointed on to an existing element. Of these 63 various repairs, all but two are completely reversible, have retained most or all of the early material, and have been carried out with little or no disturbance to the surrounding fabric. In over 30 years spent assessing the structural integrity and historic significance of timber in all types of building, my experience has been that these are typical of the genuinely traditional repairs to be found in most old buildings. In general, these types of repair can be summarised as ‘repair by addition’. By contrast, the approach most often espoused and adopted today, and commonly thought of and described as ‘traditional repair’, involves the removal of degraded timber and its replacement with new sections or complete elements connected to the old with joints derived from those used in its original construction. While repairs of this type can certainly be found in work that pre-dates the rise of ‘conservation’, they are relatively rare and should perhaps be described more accurately and simply as carpentry repairs or ‘repair by replacement’.The use of the term ‘traditional repairs’ in this context is somewhat misleading, even to the extent perhaps of lending them a spurious authenticity. Timber joints used for construction were usually placed in zones of low bending or shear stress, and both elements were at the same moisture content. When the same joints are used for repair, they can often fail because they are located in areas of high stresses, and shrinkage in the new element will tend to open up the joint. In this case, the host timber has sheared along the grain, allowing the joint to open up. This simple scarf-jointed section at the end of a brace is a simple and effective carpentry repair. This proprietary galvanised strap may not have the aesthetic appeal of a forged bracket, but is nevertheless an effective, economic and very conservative repair.
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