The construction industry is one of the largest energy consumers and CO₂ emitters in China. This paper primarily aimed to explore the driving forces of energy-related CO₂ emissions (ECE) from the construction industry. Adopting a comprehensive decomposition approach, this study decomposes the changes in ECE into eight factors. The main results provide the following findings. (1) Industrial activity was the largest factor pushing the growth of CO₂ emissions, driving up CO₂ emissions in all years and contributing to a 174.65 Mt CO₂ emissions increase in total. (2) In contrast, advances in industrial output technology represented the dominant factor inhibiting CO₂ emissions, cumulatively reducing CO₂ emissions by 99 Mt. (3) The effects of potential energy intensity changes and industrial output technical efficiency fluctuated in different years but exerted positive effects on CO₂ emissions over the entire period. (4) Additionally, changes in spatial structure, energy-saving technology, and energy consumption structure as well as energy usage efficiency all contributed to emissions reductions to varying degrees. The CO₂ emissions of the construction industry increased in all provinces, while emissions changes and their factor effects varied distinctly across provinces.