A bottom-up subnational physics-based model has been developed in this paper to estimate the residential heating energy consumption in China's Hot Summer-Cold Winter climate region. This model is constituted of data collecting module, core calculation module (including occupant behavior modeling component, building simulation component and aggregation component), calibration module and prediction module. In order to investigate occupant heating behaviors in this area, a field measurement and questionnaire survey has been carried out. This model is validated by comparing the modeled heating energy consumption with the investigated. It is calculated that currently the residential heating energy usage is 9.8 kWh/m(2) and is predicted to rise by 31% due to the increase of residents' expectation for indoor environment. Sensitivity analysis shows that residential heating energy consumption is significantly influenced by heating triggering/set-point temperature. The households with the retired consume averagely 47% more heating energy than those without the retired. (C) 2015 Elsevier B.V. All rights reserved.