The emission rates of volatile organic compounds (VOC) from building materials and the resulting indoor concentrations are influenced by temperature. Radiant floor heating systems are widely used in most residential buildings in Korea, and VOC emissions from flooring materials increase as the floor temperature rises. In this study, a numerical model is presented to evaluate the VOC emissions from building materials at different temperatures depending on the heating conditions. A coupled model is developed to simulate the temperature variation of building materials and VOC emissions in the floor heated space, which combines the building heat transfer model for materials and indoor air temperature with the mass transfer model for VOC emissions and indoor VOC concentrations. The model was validated by a mock-up test, and it was then used to examine the emission characteristics from flooring materials under different heating conditions. The results show that emissions of VOC from flooring materials tend to increase as the floor temperature rises during the heating condition.