Durham Cathedral Open Treasure

  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall
  • © Andy Marshall

Application Type

AABC Conservation

Level of Award

Award

Region

North East

Local Authority Area

Durham

Information about this scheme

The Dean and Chapter’s objective for the multi-phased Open Treasure Project is to widen public access to the hidden treasures of the cathedral, both architectural spaces as well as the collections.  A key project aim is to implement a business plan that maintains the Cathedral Church as free of entry charge to all who visit, whilst developing other sustainable revenue streams through fee charging exhibitions, improved restaurant hospitality and retail offers.  The construction materials divided into two categories.  Interventions were executed in contemporary modern materials, such as low iron, low reflectance structural glazing with natural metal detail; this enabled a clear distinction between old and new, and created clear visibility of the heritage without distraction.  Lighting was a key component in revealing the form and surface of the historic spaces.  The materials for repair were complex; analysis of the historic lime mortar confirmed that it contained magnesium from its magnesium limestone base, this has reacted with atmospheric sulphates to create a highly soluble and damaging salt that resulted in stone decay.  The poor environmental conditions within the space resulted in these salts oscillating between the soluble and crystalline state and therefore was resulting in surface deterioration.  A range of different lime repair and lime mortar techniques were used to consolidate the surface and manage moisture migrations without further decay.  This comprised lime putty, hot lime and NHL.  Much of the repair was carried out by the in-house masonry team whole were trained through the project in the use of hot-lime technique.  Some very limited stone renewal took place; a stone of matching geology, strength, chemistry and visual character was identified as an outcrop of the existing stone type which is no longer quarried locally. Much of the stone decay was repaired using stone slips and lime mortars. Repair is always honest, whilst seeking to maintain the overall special character of the historic building and conserve in-situ the upstanding above ground archaeology of the fabric.

Credits

Conservation Architect

Purcell

Structural Engineer

Patrick Parsons

Main Contractor

Simpson York

M&E Engineers

Tobit Curteis Associates

Primary Use Class

Class D1d - Display of Works of Art