The perspirable building has a perspiration function by simulating the mechanism of concentration gradient, osmotic pressure, capillarity, mechanical energy and electric potential difference controlling perspirable action in a human body. The perspiration function in the building manifests itself with the construction of perspirable roof and wall (window) using thermo-sensitive hydrogel as a new material. The thermo-sensitive hydrogel is absorption/desorption resin with thermal reversibility; water is absorbed below a specific sense temperature and desorbed over the temperature, like perspiration in a human body. It is the evaporative cooling performed not by water sprinkling onto the roof but by the autonomous perspirable function of the wall.