Heritage health : material diagnosis of the Blue House in Hong Kong

Abstract

Material science has been gradually introduced to the field of heritage conservation in Hong Kong, amassing past project experience over the last decade. Choosing the right materials is of vital importance in sustaining the life of a heritage building, in addition to the common concern of usage and alignment to the conservation principles. With incompatible materials, heritage fabrics are subjected to accelerated deterioration or even increased structural risks. However, existing studies on historic buildings primarily focus on historic research, heritage significance, conservation principles and policies with limited information on the physical condition of the buildings. This paper aims to provide understanding on the building materials of the Blue House, as a brick-wall and timber-floor construction, through effective condition survey and investigation with the aid of thermography. The physical status of the building’s materials is identified, with discussion on the possible causes of their physical deterioration, focusing on the incompatible application of cement slurry. The lack of maintenance and the presence of inappropriate repair are also discussed as the major accelerators of physical deterioration, beyond environmental deterioration, which should be carefully avoided in future restoration. Following the condition survey, this paper reveals the currently undisclosed, proposed physical conservation approach of the Blue House. It is hoped that through this study the physical condition of the Blue House and its proposed treatment can be better understood, and that the general attitude towards material conservation in Hong Kong and the feasibility of its wider application can be obtained.