The Ham Hill stonework to this late Victorian residential mansion block overlooking Hyde Park was found to be in an extremely advanced state of decay, particularly the modillioned cornice, which had failed due to the poor drip detail of the original leadwork, and the rendered parapet.
All the cement based render was carefully removed from the parapet and using progressively finer grades of carborundum pads, the Ham Hill stone was resurfaced, with great care taken to avoid damage to the carved decorative wreaths which were protected with a shelter coat.
The use of natural stone on this occasion was limited to the replacement of some of the ashlar blocks only. Using a specially prepared Ham Hill stone restoration mortar, extensive reinforced repairs were carried out to the soffit and face of the cornice and to the hood mouldings above the windows. To the areas of stonework that were not repaired, all loose and friable material was removed prior to consolidation using twenty applications of lime water. All defective pointing was then replaced.
To the balconies, some of the York stone slabs had been damaged by embedded rusting ironwork. All areas affected were thoroughly cleaned with a wire brush and treated with phosphoric acid and zinc phosphate and the fractures repaired using resin injection. To complete, Code 5 lead was re-fixed to the cornice and hood mouldings.
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