The sustainable restoration of historic masonry : Robben Island

Abstract

This poster presents the results of an experimental investigation into the physical properties of the cementing materials from the 1700s and 1800s. The samples were collected from the South African political heritage building, Robben Island and analysed. The original plaster, render bedding mortar and floor material from the island’s oldest buildings were composed of seashell aggregates and lime as binder. Some sections of the render, plaster and raised pointing were cement-based. These take up a minority area of the buildings and were referred to a recently repaired areas. In most areas where such cement‐based materials were used, the materials show signs of detaching from the original surfaces