Conservation Progress

• Current Conservation And Development Projects
  • South East Transept
  • The Corona Chapel
  • Choir House
  • Conservation - Stonemasons

South East Transept

The work on the South East Transept is a continuation of that recently completed on the exterior of the chapels of Saint Anselm and Saint Gabriel. The interlaced arcade decorating the lower level of the apses is typically Norman or Romanesque in style and probably dates from the 12th century, although it was extensively restored in the late 19th and early 20th centuries. It is this well-intentioned but catastrophic intervention that is responsible for much of the deterioration that we see today.

A combination of inferior quality Caen stone from northern France and hard, impermeable cement mortar has accelerated the decay of much of the carved detail. The work at higher level contains more original material, but from a slightly later date.

Areas of black sulphate crust have been removed from the stone. As well as looking unsightly, if left untreated this will trap harmful salts behind the face of the stone and speed up the cycle of decay. The usual method of cleaning combines applying a poultice followed by gentle abrasion with a pressurised spray that mixes a fine aggregate, of a similar hardness to the stone, with water. The machine looks and sounds more aggressive than it is and uses the minimum amount of water for it to be effective.

Finished stone has been fixed into the building using mortar made from lime putty, sand and stone dust, just as the medieval masons would have done. After the stone has been fixed liquid mortar or grout is poured in behind to fill any gaps and to bind the stone into the core of the wall. The Cathedral is constructed of two walls an inner one and an outer one and the gap between is full of rubble and mortar. Every so often a larger stone has been positioned to tie the walls together for added strength. The rectangular holes that are visible all over the exterior are called putlog holes and mark the place where the original horizontal scaffolding timbers were.

Most of the work carried out by the Cathedral masonry team is on the outside of the building as this is subject to decay caused by our lovely English climate!