This paper compared vertical temperature distribution between the existing balcony model without ventilator facilities and the improved balcony model with ventilator facilities using differential equation. As the air inside of balcony is heated by solar radiation this heated air is not exhausted in the existing balcony, remaining stagnant. The air temperature distribution was $26.7{sim}29.3^{circ}C$ in balcony without natural ventilator system. This heated air affected the rising air temperature of adjacent spaces such as living room and bedroom in the existing balcony. But, as the heated air inside of the improved balcony model is exhausted through natural ventilator facilities in summer, the air temperature in balcony has fallen. The air temperature distribution in improved balcony was $24.8{sim}26.7^{circ}C$ for the inlet air speed of 1 m/s and $24.6{sim}26.7^{circ}C$ for the inlet air speed of 3 m/s. The energy consumption of the improved balcony is 2.5 times less than of the existing balcony. The improved balcony with the closed damper makes a roll as the existing balcony in the aspect of the heating effect. When the heated air in the improved balcony is supplied, the air temperature is raised and the ventilation effect in adjacent spaces was improved.