This thesis investigates theories of conservation of architecture and how they are demonstrated in contemporary practice. In undertaking this study, the development of current thinking about conservation is initially considered through a survey of historical texts which identify two distinct approaches in the nineteenth century ideas and work of Viollet-le-Duc in France and John Ruskin and William Morris in Britain. Underpinning these two positions are two different understandings of the meaning and purpose of architecture. These two stances have been sustained throughout twentieth century debate and practice and continue to inform texts and design outcomes today. It is in the context of this debate that charters and legislation, used to guide and control contemporary conservation throughout the world, are formed. The Burra Charter, as the foremost document for conservation practice in Australia is further considered in terms of how it contributes to contemporary conservation practice.
Having established the theoretical framework, the practical application of conservation policies is tested in the two local case studies of the Brisbane Customs House and the Commissariat Store. In the specific analysis of the case studies, the action of the conservation work reveals an approach towards conservation, and from this, the thinking which underpins each is also revealed.
Tracing the thinking of nineteenth century theorists across the twentieth century and through to their application in contemporary practice, conclusions are drawn as to what constitutes a theory of conservation for the modern era. Contemporary conservations involve an initial critical analysis of the values inherent in the subject work of architecture. There are plural approaches to contemporary conservation and the specific one to be adopted in each case emerges only from this initial analysis of the subject work. From an analysis of the approaches adopted, a meaning of architecture, as is relevant to contemporary practice, is understood. In the process to isolate a theory of conservation for the modern era, it becomes evident that there is no single coherent theory which informs practice today. Rather, a theory of conservation for the modern era is characterised by an initial analytical process which determines the application of the specific approach which is grounded in nineteenth century thinking.