As a UNESCO world heritage evaluator, Bernard Smith has worked in cities such as Venice, Prague and Rio de Janeiro. He has also been involved in the conservation of some of Belfast's best-known buildings including the Albert Clock and St George's Market.
Reducing atmospheric pollution has helped create purer air in our towns and cities.
What isn't so well known is that a cleaner environment, combined with changing weather patterns, is still driving significant damage to some of our most historic buildings. Sadly, a growing number of these buildings, whose stonework had deteriorated only gradually over centuries, are now undergoing unpredictable, rapid and sometimes catastrophic decay. Bernard has won funding under four separate EPSRC projects designed to establish why this should be and what can be done about it. Much of this research has been carried out in collaboration with fellow academics at the University's School of Planning, Architecture and Civil Engineering, Oxford University and City University London as well as a number of commercial partners.
"In the past, pollutants reacted with the surface of many types of commonly used building stone to create a protective surface crust. When that's removed through natural attrition or restoration work, the layer beneath is exposed and the crust won't reform because the air is cleaner than it used to be," says Bernard.
"This can result in rapid decay which can be further exacerbated by changing climatic conditions. To study the impact of these a research facility has been built a in a clean environment in the west of Northern Ireland where a diverse range of environmental sensors have been installed to measure the effects of weather conditions on different types of building stone.
"This is giving us valuable data on how the localized impacts of global climatic change could affect stone. Because the centre is located in an area with particularly high rainfall, we can use that information to predict what could happen to buildings in other locations, especially those where winter wetness is projected to increase.
"Working with our project partners, we have also used our research findings to develop sophisticated fibre optic sensors that can be assembled into networks for embedding in endangered buildings. These will give an accurate picture of the condition of the stonework and indicate if and when any remedial action is required. The most recent EPSRC funding is to bring these sensors closer to commercial development through a university spin-off company.
"Through our research we can now see that some current conservation and restoration practices not only don't work, they can actually make the situation much worse, in a world where environmental conditions are constantly evolving.
"The expertise we have developed should now help ensure that the hundreds of millions of pounds spent annually on preserving the built heritage in the UK and Ireland will be used in the most effective way possible."
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