Special Report: The Conservation ‘Grand Tour’

Special Report: The Conservation ‘Grand Tour’

As the business of repairing Britain’s heritage in bricks and mortar continues to thrive, Professional Builder’s Lee Jones reports on a unique group of craftspeople who are on a mission to acquire the essential expertise needed to preserve our historic buildings for posterity.

The men and women who have chosen the repair of ancient buildings as their vocation invariably demonstrate a considerable commitment to their calling, an attitude which is exemplified by the three tradesmen presently undertaking the William Morris Craft Fellowship.

This nationwide and educational conservation ‘Grand Tour’, organised by the Society for the Protection of Ancient Buildings (SPAB), allows a chosen few to visit multiple restoration sites over many months, experiencing everything from lime plastering to timber framing and stonemasonry along the way. Metalworker Ross Buckley, and stonemasons Naz Dmiuterko, and Gary Holliday, are spending many weeks from home, and often relying on the generosity of their fellow craftspeople for board and lodging, but these sacrifices come with considerable rewards.

“When you’re working on an old building there’s a sense of being a part of history, and a long line of tradespeople who first built then cared for it,” explains Durham Cathedral Stonemason, Gary Holliday. “So many of the buildings of old were designed to be aesthetically beautiful as well as functional,” adds Ross Buckley, “and to contribute to that tradition is the appeal.”

“The fellowship gives you the opportunity to understand and appreciate what generations past achieved without any of the tools we take for granted,” continues Naz Dmiuterko, “and it fascinates me that they produce work of often a much higher quality than now with much less.” For both Naz and Gary, the experience of lime plastering has sparked an interest that the pair hope to pursue beyond the fellowship, whilst the opportunity to work at a number of prestigious sites, with leading figures in each field, helps to forge an understanding of how the trades can work together and share knowledge on site – a principle which is ably demonstrated on the site where Professional Builder found the three fellows hard at work.

The SPAB Working Party is an annual event that seeks to put into practice the philosophy that underpins the charity. A sensitive repair, minimal intervention and the promotion of traditional materials and techniques are all central themes, each of which are much in evidence in the garden wall restoration of a remarkable 16th century survivor.

Working Party Co-Ordinator, Catharine Ball, might have a long association with SPAB, having completed the organisation’s scholarship in 2000, but the Elizabethan Manor House which is her base for eight days can claim a century old connection. “Eastbury Manor is unusual as a subject for a working party in that the fabric of the building is relatively sound,” explains the building surveyor.

This hidden East London treasure wasn’t always quite as palatial, however, and it was in fact the intervention of architect and committed SPAB campaigner, William Weir that saved the building from ruin. It then became the first property in London to be purchased by the National Trust, and its future has since been secured with regular use by Barking & Dagenham council.

“Just as with the William Morris Craft Fellowship, the working party is an opportunity for us to share knowledge, and bring a community of craftspeople together,” continues Catharine. “We then invite volunteers to work alongside them with the aim of propagating the SPAB approach to repair still further.”

It is that ambition which is exemplified in the techniques used at Eastbury. Whilst a material based on Portland cement might be the mortar of choice for the fast paced modern world, a hot lime mix was once the traditional companion to bricks. When structures of the vintage of Eastbury Manor’s 90metre expanse of south facing garden wall are repaired and repointed with contemporary sand and cement, a loss of the natural movement and breathability that lime brings serves to accelerate the process of decay. The SPAB team which, in addition to the three fellows, includes Conner Meehan of Triskele Conservation, and Hugh Conway Morris are seeking to redress the balance in favour of a traditional technique by demonstrating how a hot mix lime mortar can be made within the Eastbury Manor grounds itself.

“Lime mortar was a far more sustainable material in that it was often produced from the raw material in the vicinity of the build,” explains Hugh as he tends, alchemist-like to the vertical shaft kiln that is heating limestone to over 900°C. “Not only that but it will maintain its structural integrity for far longer than a mix you might find on a new build.” That high temperature firing burns off the carbon dioxide in the sedimentary rock transforming it into quicklime, the ancient precursor to Portland cement, but the magic of lime mortar doesn’t end there. Quicklime is a highly reactive substance and, after being mixed to a ratio of 1 quicklime to 2 ½ sharp sand, to ½ limestone dust, water is then added. The introduction of simple H2O precipitates an exothermic reaction, producing calcium hydroxide, the sand/lime mix swells to twice its original size producing considerable heat as a by-product. The material is then banked for later mixing to the required consistency, depending on whether it’s used for pointing or laying bricks.

“There is aesthetic to lime mortar that just can’t achieve with cement,” adds Connor. “Where some small pieces of quicklime have over- or under-burned in the kiln they are rendered inert, are not subject to the same exothermic reaction with water, remaining white as a consequence. That’s why you get a wonderful speckling through the pointing that is in stark contrast to the deadness of sand and cement.”

It is the knowledge of these ancient arts that the William Morris Craft Fellowship is preserving for future generations, leaving a legacy of tradespeople who are informed but why an old building requires to continue its journey into the future.

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