Reducing carbon emissions in the buildings sector is of great significance to the realization of China’s carbon peak and neutrality goals. By analyzing factors influencing buildings carbon emissions at the operational stage, this paper applies the China Building Carbon Emission Model (CBCEM) to make medium and long-term forecasts of China’s building operation carbon emissions, discussing the goals and realization paths of China’s dual carbon goals in the buildings sector. The results show that building operation carbon emissions, according to the current development model in the buildings sector, will peak in 2038–2040 with a peak carbon emission of about 3.15 billion tons of CO₂; however, by 2060, carbon emissions will still be 2.72 billion tons of CO₂, falling short of China’s dual carbon goals. The carbon saving effects of three scenarios, namely clean grid priority, building photovoltaic priority and energy efficiency enhancement priority, were measured and shown to be significant in all three scenarios, but the building photovoltaic priority and energy efficiency enhancement priority scenarios were superior in comparison.