This paper proposes an enhanced-convection overhead radiant floor heating system (EORFHS), which adds holes to an existing overhead radiant floor heating system (ORFHS). In addition, the heat flow and heat transfer of these systems were analyzed. By experimental investigations in an artificial climate chamber, the heat storage and release characteristics of the two systems were investigated and compared. The results indicated that the floor surface temperature and the room temperature were more responsive in the EORFHS during the preheating period. For the ORFHS, the pipe spacing has the strongest effect on the preheating time, whereas the pipe spacing and pipe Water temperature have the same effect on the preheating time for the EORFHS. The relationship between the two systems for the intermittent period and the preheating period was also obtained. For the EORFHS, the number of holes per floor unit has a minimal effect on the floor surface temperature. The outlet air experienced natural convection with an average wind speed of 0.1 m/s. The numerical simulation method was proven to be accurate; the error between the numerical simulations results and the experimental results was less than 9%. (C) 2016 Elsevier B.V. All rights reserved.