In recent decades, energy problem has been discussed and numerous energy problem oriented researches have been continuously conducted. Environmental issue contains not only resource input issue, but also waste output issue. Therefore, it is very essential to grasp a certain principle regarding waste output issue and to apply it into existing such problems. Entropy is quantity of generation, and it is suggested by Atsushi Tuchida and Atsushi Kachiki who are Japanese physicists that discarding entropies through systems forming multiple-layer structure can maintain the sustainability of systems. If entropy balances analysis is applied into problems in rack of heat discarding capacity, it might enable us to articulate the principle for “design of discarding” in thermodynamic sense. From such a background, the authors calculated entropy balances about human body, room air, walls, and air conditioner for grasp to principles on entropy balances in multiple-layer structure consisting of various component in built environment with and without onset of heat stroke. Followings are findings. 1) In case of comfortable indoor climate with air conditioning, entropy generation rate in room air and walls are 1.28W/K and 39.06W/K, respectively. On the other hand, at the onset of heat stroke without air conditioner use, entropy generation rate in the room air and walls are 0.22W/K and 10.07W/K, respectively. 2) There are difference in entropy disposal of 0.05W/K from human body of 3.39W/K from room air and that of 29.17W/K from walls, between comfortable indoor climate and onset of heat stroke. It is essential for these working systems to ensure all entropy disposal with sufficient amount in order to avoid dysfunction originated excessive entropy accumulation. 3) In case of comfortable indoor climate, changes in entropy generation rate of the shell of human body, room air, walls and air conditioner correspond to fluctuation of surrounding temperature. On the other hand, at the onset of heat stroke, changes in those entropy generation rate don’t correspond to fluctuation of surrounding temperature.