Government policies aimed at reducing energy use have focused on technical aspects of building structures, not residents' behaviors in households. However, many studies have argued that residents' behaviors might play a prominent role in the reduction of energy consumption in households. Compared to the impact of buildings' features on energy use, little research exists that considers household characteristics in addition to building features in analyzing the effect of residents' behaviors on energy use. Thus, this study aims to obtain an insight into the effect of residents' behaviors on energy use. Our research starts from the assumption that there are some differences in energy consumptions between households with different service life. To investigate the energy consumption in 20 households, we visited maintenance offices to obtain the metering data, and conducted in-depth interviews to investigate the residents' energy use behaviors in terms of heating, cooling, bathing, cooking, lighting, appliance and ventilation. Contrary to our expectation, it was identified that the households in the 33-year-old apartments did not use more energy than those in the 11-year-old apartments. Rather, energy conservation behaviors have more effect on energy consumption, regardless of the service life of buildings. (C) 2013 Elsevier B.V. All rights reserved.