Abstract
Urban construction has been a major contributor to carbon emissions. As China's housing demands decelerates, addressing the vacancy of residential buildings has become essential for revitalizing the real estate sector and promoting low-carbon and circular urban development. Here we show that China's housing vacancy rate within the available residential building stock may have exceeded 30% since 2021. We assess three strategies to transform excessive vacancy into an opportunity for carbon neutrality: (i) demand-side mitigation by housing vacancy rate reduction to slow down near-term carbon emissions, (ii) supply-side mitigation through the renovation of old residential buildings, and (iii) restricting demolition for sustained carbon reduction. These three strategies collectively yield superimposed carbon mitigation benefits: moderate implementation could reduce China's urban residential construction emissions by more than 43% over 2023-2060, meeting a 2 °C-compatible carbon budget under the Sustainability Shared Socioeconomic Pathways and offering a transferable framework for low-carbon, resource-efficient urban construction.