20 C O N T E X T 1 4 4 : M A Y 2 0 1 6 India House, Manchester At India House, Manchester, the scaffold itself was the subject of a listed building application, because of the potential it had to cause significant damage to the historic fabric. A tied independent scaffold was required to this citycentre building for routine maintenance. Typically this involves drilling fixings into the building facade, giving the scaffold lateral support, while allowing vertical loads to pass down the scaffold. Unusually, listed building consent was required for the scaffold itself, not the work to be performed off it.This was because of the growing damage to the facades over the decades from a number of previous scaffolds. To help understand why this was such a cause for concern, the context is that India House, built as a steel-framed packing warehouse in 1912, was listed in 1974, along with three other similar adjacent buildings, as Grade II*. Together they have been cited as ‘virtually minor skyscrapers with details derived from contemporary American tower blocks3. The facades, consisting of an Aberdeen granite plinth, glazed Sienna terracotta work and red Accrington brickwork (between the areas of terracotta) are a major part of the building’s historic significance. Buildings of course require routine maintenance from time to time. It is likely that this building will have been fully scaffolded three or four times to date. This was beginning to take its toll on the terracotta, where numerous ties had been installed to restrain past scaffolds. Recognising that this was a growing problem for the adjacent terracotta buildings too, Historic England and the planning authority requested a method of scaffolding be devised which would not cause further damage, and which could be applied more generally to the neighbouring buildings as well. To be a workable solution that scaffolding firms would be willing to adopt, it needed to conform to industry standards, such as theTG20:13 guidance.This dictates ties at maximum 4m centres vertically and horizontally. The guide details a number of different fixing methods as well as the familiar anchor tie. Ultimately the solution involved the use of reveal ties where necessary, as well as identifying locations where the use of anchor ties was acceptable. Reveal ties are anchor points formed by screw jacking against the window reveals (with timber blocking pieces). Just like anchor ties, the guidance recommends that a number are load tested to ensure that they are adequate. Despite this, the scaffolding firm involved was uneasy about relying too much on reveal ties. Hence the solution, which achieved the listed building consent, involved a hybrid approach including other tie methods too: return ties at the corners (the guide recognises that where a scaffold continues around a corner, this contributes to its overall stability, and hence allows this in lieu of a set of ties to the fabric); anchor ties to the Ackrington brickwork, utilising existing anchor holes from past scaffolds where practical; and reveal ties to the windows in the areas of Sienna terracotta. At India House, Manchester, numerous ties had been installed to restrain past scaffolds. access scaffold was required in order to inspect the tower at high level, to inform a programme of repairs. This scaffold shows simple measures designed in to the proposals and implemented on site to safeguard the historic fabric. These include: the scaffold is not tied to the tower masonry, but instead has raking stays to hold it in place; the scaffold butts up to the tower via a series of timber pads; where the top lift runs over the nave roof, for this light duty use, sandbags dissipate the point loads, protecting the tiles.
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