High household end-user services demand of high-income families results in higher energy consumption compared with low-income families, indicating high-income families may save more energy from similar building energy retrofitting (BER) strategies. Therefore, current BER subsidy policies, which consider technique indicators and ignore families' income, will make high-income families' recovery costs faster, and can't maximize the incentive for residents’ BER awareness. To formulate a equitable and efficient subsidy policies considering families’ income, this study selected Chongqing as the study case and employed propensity scores matching method to evaluate BER's actual energy savings performance for families with different incomes. Meanwhile, the BER subsidies are reallocated based on the dynamic cost payback period. The results indicated that, following BER, the energy savings of high-income families (7.36 kWh/m²) were higher than the mid- (3.96 kWh/m²) and low-income (3.25 kWh/m²) families. Notably, under current subsidy policies, the cost payback period of low-income families is nearly 2.55 and 3.14 times of the mid-income (6.61 years) and high-income (5.37 years) groups, respectively. This study suggests a subsidy of 32.57 yuan/m², 20.27 yuan/m², and 15.38 yuan/m² for low-income, mid-income, and high-income families, respectively. These results provide novel insights into the actual energy-saving performance of residential buildings and help policymakers to formulate fair subsidy policies.

Under China's national strategy of carbon neutrality by 2060, it is urgently necessary and challenging for the governments to proactively explore policy tools to facilitate energy-efficient renovation of existing buildings. Currently, a considerable number of studies have been conducted on building energy-efficient renovation and its derivative topics, however, a comprehensive overview on incentive initiatives related to existing renovation practices in China is still scarce, such as a lack of critical correlation analysis between national and local initiatives, a lack of the synthesis and critique towards the latest policies and related achievements, and inadequate generalization of the diverse and multi-layered barriers and challenges in building energy-efficient renovation practices. To address these issues, this paper adopts a diversified policy segmentation approach to deeply analyze the dynamic evolution of the incentive initiatives from both national and local level perspectives, as well as to establish the related network of policy linkages between national to local, and between different localities. In addition, this paper presents a critical analysis on representative initiatives in two batches of pilot cities, and proposes good practices and valuable experiences for building energy-efficient renovation. Finally, this paper further summarizes and discusses the barriers to building energy-efficient renovation from four perspectives: governments, householders, enterprises and research institutions, and proposes a series of targeted and feasible pathways and strategies. This study can provide theoretical guidance and targeted recommendations for the formulation of policies, standards and regulations for building energy-efficient renovation in China.

In China, dynamic spatial–temporal evolution and urban–rural gap in carbon emissions of residential building sector are crucial for understanding the current state, which is faced with great challenges related to emission mitigation. To overcome the challenge, this study employed the gravity center model to explore spatial–temporal evolution of carbon emissions and analyzed the driving factories leading the differences between urban residential buildings and rural residential buildings via decomposition analysis. Meanwhile, Tapio decoupling index is used to predict the future movement of the gravity center. Our results indicated that: (i) the carbon emissions gravity center of both residential building types tends to move south; (ii) the northeast and northwest regions play the largest role in driving the gravity center movement of urban residential buildings and rural residential buildings, respectively; (iii) per capita disposable income is the primary factors affecting the gravity center movement. (iv) the gravity center of both residential building types might tend to move westward in the future. Overall, this study attempts to remedy the current lack of research pertaining to spatial–temporal evolution laws governing carbon emissions in the Chinese residential building sector and provides a reference point for the implementation of targeted urban and rural emission reduction policies.