In practical engineering application of radiant floor cooling system, both floor surface temperature and the lowest temperature in surface are more concerned because the former determine cooling capacity and indoor thermal comfort and the later is a key parameter for preventing condensation in floor surface based on consideration of the dew point in the indoor environment. In this paper, a simplified thermal calculation method for multilayer floor structure in radiant floor cooling system is proposed. Based on the analysis of heat transfer process of floor, the equivalent thermal resistance method is developed and some formulas are derived to estimate floor surface temperature distribution. The simplified calculation method is validated by experiments. The absolute error between simplified calculation and experiment results of floor surface temperature is within 0.4 degrees C. By this proposed method, it is helpful to easily estimate floor surface temperature distribution and analyze the influence of parameters of floor structure on thermal characteristic of floor. (C) 2014 Elsevier B.V. All rights reserved.