Urban household carbon emission reduction is an important research field under the current background of global climate change and quick urbanization process in China. This paper introduces a social technical analysis of household residential carbon emissions. Building and occupant data of sample households was collected through post occupancy monitoring, electricity and gas meter records, photographs and questionnaires. The data provides insight into different household patterns for controlling the HVAC (heating, ventilation and air conditioning) systems. The case study relates the occupant behavior, thermal environment and energy consumption. The result can serve as tools for informing occupants about low carbon lifestyles and more energy efficient ways to control the thermal environment.