2010 Yearbook

r e v i e w 41 Team work John Hoath The success of any project relies on the skills of the project team and the close co-operation and relationship between its members. This includes not only the consultants and contractors, but also the client’s representatives and the conservation officers from the relevant authorities. Trust is a key ingredient. On heritage work the relationship between members of the team is particularly important as, even with the most rigorously researched and prepared specification, it is rarely possible to anticipate all aspects of the work required. Unforeseen difficulties often arise during the opening up of historic building fabric for repair, resulting in much technical and philosophical debate taking place on the scaffold as the work proceeds. Decisions often need to be made on the spot. This can be highlighted to great effect by recent works undertaken to the masonry on Cranmer’s Tower at Lambeth Palace. Repairing cranmer’s tower Cranmer’s Tower was built during the incumbency of Thomas Cranmer, Archbishop of Canterbury to Henry VIII, during the early 1540s. Built predominantly of red brick with stone dressings, Cranmer’s Tower was distinguished, as many dignified buildings of the period were, with a glazed brick diaper pattern to the façade. During the intervening years the tower has seen much well intentioned but inappropriate ‘restoration’. Many schemes were carried out over the decades, most notably during the mid Victorian period when Edward Blore was the palace architect, and later following bomb damage in the second world war. The use of black ash/cement mortar in the 1950s for re-pointing the soft red bricks of the Tudor period had caused untold damage to the structure. In particular, the castellated brick parapet was in extremely poor condition in places, with widespread cracks and deformations. The original brickwork to the parapet had been dismantled during Blore’s time as architect, probably due to its extremely poor condition: in fact he himself described the buildings at Lambeth Place to be ‘miserably deficient’, during his survey in the 1830s. The parapet had been replaced with a much harder stock brick, bedded in a hard cementitious mortar, and fixed with iron cramps as was common at that time. This created a rigid structure founded on the much softer lime-based Tudor work. The result, all too familiar today, was damage caused by differential settlement and frost heave, and the parapet bowed in and out, leaning alarmingly in places. Once full access to the parapet was gained by scaffolding, a decision was needed urgently on how to proceed with the correct repair strategy. Roughly 70 per cent of the parapet was found to be severely impaired. Furthermore, much of the remaining structure was showing signs that significant failure could occur in the near future. The rebuilt parapet and chimney. The chimneys had been rebuilt in the Victorian period with brickwork in the style of the original stone chimneys, but only one had to be rebuilt as part of the current programme, using a combination of salvaged and newly cut bricks.