Abstract/Summary

Energy consumption and carbon emission have become a challenge in old residences in China. Old residential buildings remain dilapidated with their poorly insulated building façade and significant potential in energy and carbon conservation. Yet the current circumstances are found very complicated due to the unclear reality and complex nature of the diversities of building conditions, resident preferences, economy, and social factors of coordination and motivation. Retrofit of urban residential buildings (RURB) is treated not as a systematic research topic, but rather as a project-based construction process in current knowledge. This linear thinking has been argued which caused empiricism problems since interconnections between retrofit system participants are notably neglected. To achieve the research objectives and justify the system thinking perspective, this thesis explores and understands the system cognition and interactions of the Retrofit of Urban Residential Buildings (RURB). The adopted system thinking method, interviews, and questionnaire survey methods are used based on causal layered analysis for the comprehensive system definition, boundary, variables, and participants. System interactions between system players and variables are also analysed by using the causal loop diagram method, hence systemic problems can be discovered. With this theoretical basis, a case study of the Chongqing city zone is selected to support the system theory with urban retrofit effects. Results of retrofitting benefits and costs are obtained through modelling, field survey, energy simulation, and calculation approaches. They are evaluated as five retrofit criteria of energy, cost, comfort, function, and safety improvements. A total of the six retrofit scenarios with four referencing building types are applied to multi-criteria decision-making analysis, as the analytic network process for the weighted values of retrofit benefits and costs. The retrofitting potential, solutions for systemic problems, and hence the suggestions for future policymaking are found and discussed. This research develops an innovative and coherent method to support future RURB decision-making and policymaking by providing both a theoretical basis and reliable data source, which can become a generalised approach to RURB analysis in other city conditions.