The Building Conservation Directory 2021

BUI LDING CONTRACTORS 2 55 C AT H E D R A L C O MM U N I C AT I O N S T H E B U I L D I N G C O N S E R VAT I O N D I R E C T O R Y 2 0 2 1 ACCESS SPECIALISTS RPF Scaffolding Ltd, 284 High Road, North Weald, Essex CM16 6EG T: 01992 524411 E: W: FLEETOPERATOR RECOGNITIONSCHEME Encompassing The Old Bailey through to The Bank of England and ‘The Journalists’ Church’ in Fleet Street amongst many others, NASC-established RPF Scaffolding Ltd has been undertaking complex and considerate conservation scaffolds since 1982. Scaffolding Specialists to the Conservation Industry NationalAccess&Scaffolding Confederation PROTECTION Electrical earthing of a scaffold is another important consideration for the conservation team. The pre-construction information should identify whether the building to be scaffolded has an external lightning protection system, and whether there are any specific requirements for earthing the scaffold. In addition to the usual variability of resistances of different soil types, there may be areas of significant archaeology, landscaping or garden features associated with the historic environment which may lead to difficulties in achieving a sufficiently low electrical resistance with conventional terminals. If the scaffold is on a scheduled monument, consent would be required to drive even temporary earth terminations into the ground. Locations for disposal of rainwater from a temporary roof should also be included in the pre-construction information, taking into account any archaeological sensitivity, particularly if saturation or erosion may result. Where discharge is onto land that is a scheduled monument, the work proposed should be included in the application for consent. If scaffolding is to be in position for an extended period it is important to prevent unauthorised access, such as removing or preventing access to ladders when not in use, removing boarding from scaffold lifts, installing an alarm system, or enclosing the scaffold with fencing proportionate to the perceived risk of trespass. ERECTION AND DISMANTLING Erection and dismantling of scaffolding generally takes little time and can involve a high number of scaffolders in a relatively small area. Impact damage to historic fabric most frequently occurs during erection or striking scaffolding, mostly due to the long lengths of the tubes involved. It is important that the principal contractor is adequately briefed on the significance of the historic building and the level of care that is expected, so that they can adapt their site rules, inductions and toolbox talks accordingly, and brief the workforce to ensure they are engaged in undertaking their work in a way that minimises risk. Recommended Reading BSI 2011 Code of practice for temporary works procedures and the permissible stress design of falsework, BSI Standards Publication BS 5975:2008+A1:2011, Incorporating Amendment No 1., London: BSI BSI 2003 Temporary works equipment. Scaffolds – Performance Requirements and General Design, BSI Standards Publication BS EN 12811-1:2003, London: BSI Health and Safety Executive Scaffold checklist scaffoldinginfo.htm Historic England 2008 Conservation Principles, Policies and Guidance , Swindon Historic England 2015 Piling and Archaeology; Guidelines and Best Practice, Swindon Historic England 2019 Lightning Protection, Swindon Ed Morton, 2008 ‘Scaffolding Historic Buildings’ Journal of Architectural Conservation , pp 23–42 National Access and Scaffolding Confederation (NASC) TG20 suite of guidance tg20-suite/ National Access and Scaffolding Confederation (NASC) TG4:17 Anchorage Systems for Scaffolding information/tg20-suite/ John Ruddy, 2015 ‘Conservation compendium Part 12: Scaffolding of historic structures’ The Structural Engineer pp 40–44 BRIDGET DRAKE-WILKES is a conservation accredited engineer and a senior member of the structural engineering team at Historic England. She has over 20 years’ experience, over half of which has been spent working with listed buildings and scheduled monuments.