C O N T E X T 1 1 2 : N O V E M B E R 2 0 0 9 9 The latest issue of the Association of Preservation Technology Bulletin (Vol XL, No 2, 2009) features articles presented at the association’s 2008 annual conference in Montreal, Canada. Ronald Anthony, Kimberly Dugan and Deborah Anthony kick off the issue with an article on grading protocols for structural lumber and timber in historic buildings. They give an overview of the history of standards and grading rules for wood. These rules determined appropriate design values that would reduce the need to replace historic fabric. This would reduce costly, and often unnecessary, replacement decisions. The writers explain a computerbased wood-grading program that can be used by architects and engineers. A grading protocol is not to intended to make every conservation professional a certified grader, but it does permit more informed decisions about the structural capacity of wood members in historic buildings. Robert Score and Bradford Carpenter explore thermal performance of repaired and replacement steel windows, a topic of current concern to those dealing with energy conservation and increasing building regulation requirements in the UK. They use the example of the Lafayette Building in Washington, DC. Through detailed analysis of in-situ thermal monitoring of solar heat gain, conductive and radiation heat loss, they demonstrate that such windows can be repaired.What is more, they will out-perform modern aluminum-framed replacements. As requirements grow for a greater proportion of renewable energy to be generated on-site in new developments, it is invaluable to see ways in which this could be done by the use of geothermal heat pumps for historic buildings. The article explains how the system works, life-cycle cost of geothermal heat pumps, the supervision of well drilling and installation (as they are typically located along the building’s perimeter), mitigation measures, and post-installation maintenance. It makes reference to two practical examples: the massive neo-Romanesque Trinity Church by HH Richardson (1877), and the Georgian revival Byerly Hall at Harvard University (1932). Pressures of time and funding rarely permit retrospective evaluations of repairs. So Sven Thomasen’s article, looking at restoration of terracotta at the Atlanta City Hall in Georgia over 25 years ago, is helpful in giving an extended perspective of its success. The author looks at key aspects such as maintenance practices, repair of damaged terracotta, and joint treatments. Many of the repair procedures and restoration materials are still in common use. The 1980 project involved choices and compromises such as the use of concrete blocks in place of terracotta, in situ repairs of minor defects, and a strategy of relying on a programme of periodic maintenance rather than eliminating all defects. Thomasen concludes that this strategy has proved a qualified success. The rate of deterioration has been controlled, but fairly regular maintenance remains essential. The final article focuses on conservation treatments for ancient earthen structures in the Western Himalayas of India. Charu Chaudhry and Sandeep Sikka put forward a methodology of structural analysis conservation of roofs, wall plates and exterior render. They propose maintenance manuals with priorities for owners and occupiers. The occasional 80-page pullout section Practice Points features the second part of Lorraine Schnabel’s three-part series on mortar analysis. In this series, the author covers analytical methods including petrographic analysis, x-ray diffraction, scanning electron microscopy and energy-dispersive spectroscopy, and chemical analysis. After the fiasco of the disappearing Heritage Bill, Cornerstone, the newsletter of the SPAB (Vol 30, No 3, 2009), has highlighted the disappearing financial resources for heritage. The SPAB highlights that between 2000 and 2008, the government cut English Heritage’s funding from £144 million to £125 million. Meanwhile, £90 million of Lottery funding was diverted from heritage projects to the Olympics. Visitors to English Heritagestaffed properties fell by 10 per cent over 10 years to 5.3 million in 2008. The French president Nicolas Sarkozy recently announced a €100 million rise in funding for heritage conservation in France, as part of an economic package to boost the economy. The SPAB has asked what we can expect from the politicians on this side of the Channel. A DCMS spokesperson reveals that Ben Bradshaw, the current secretary of state, has ‘no plans to increase heritage spending’. But the opposition parties are as yet unconstrained by office or the state of the books. The Conservatives propose ‘more money to back the initiative and enthusiasm of heritage organisations’. The Liberal Democrats suggest that ‘funding has been cut, but putting money into heritage could boost the economy’. The Greens advise that ‘we should be looking after our national heritage as part of a recovery plan’. The issue reflects in depth on the SPAB’s epic barns campaign, nearly 30 years on. At the time, traditional farm buildings were at risk as never before. Many were converted unsympathetically to residential use, while many more were abandoned to decay by changing farming practices and government grants for new agricultural buildings. The society’s mammoth survey led to its Barns Book in 1982, its Barns Committee, and its Doomsday Survey of Barns in 1984. Philip Venning describes in detail this project and the changing attitudes of the Ministry of Agriculture, among others. These led to 30 per cent grant aid towards assisting the repair of traditional farm buildings. Venning highlights that as far back as 2005, Heritage Counts estimated that £30 million would be needed just to repair the 2,400 listed farm buildings in a ‘severe state of disrepair’. This when only five per cent of all farm buildings are listed. However, some funding is available through agri-environment schemes. Susan Hardwick, Natural England’s senior historic specialist, reprises the issues she discussed in the July issue of Context. Bob Kindred MBE
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