Green building technology applied to urban residential development can produce significant economic and ecological benefits. In this paper, green design and construction of urban residential buildings is carried out from the perspective of floor area and other aspects. The Nanjing CF project is selected as the research object to analyse the impact of green building technology on its project cost and environmental sustainability. A fuzzy exponential smoothing model is constructed based on fuzzy mathematical theory and exponential smoothing method to estimate the project cost of the CF project. Carbon emissions during the whole life cycle of the building, including the production of building materials, are measured to illustrate the environmental sustainability of the green building technology.The green building technology used in the CF project results in a significant reduction in the cost of roofing materials and maintenance costs compared to conventional roofing. With a base year of 2023, the CF project will pay for itself in full in 25 years, both in terms of construction and maintenance costs. Compared with traditional buildings, the green building in the CF project has reduced carbon emissions at all stages of the whole life cycle, and the total building carbon emissions are 9.72% lower than those of traditional buildings.
