Click on image to enlarge

Cyphers - Hampton Court Palace, Base Court

Conservation of 16th century Cyphers

The two Caen limestone cyphers are a small but significant part of the building history at Hampton Court. Not only do they have the earliest surviving date in the palace (1566) carved on them, but they also mark a phase of building work undertaken by Elizabeth I. Their continued survival and the retention of the remaining detail was of paramount importance.

Both cyphers were in an advanced state of decay due to natural weathering, the formation of sulphate crusts and decay brought on by poor detailing of the drip on the string course above resulting in the dissolution of the stone matrix.

A careful process of cleaning was undertaken using a  weak ammonium carbonate poultice. Where the stone was crumbling badly a thick lime putty slurry containing finely sieved stone dusts and sands was used as an initial consolidant. Mortar repairs were applied as bothcapping/holding repairs and to slightly build up eroded details that were difficult to read from the ground. Finally two coats  of a lime shelter coat were applied.

Client: Holloway, White and Allom
Architect: Martin Ashley