Abstract
The summer heat due to global warming is getting progressively worse each year. In particular, the unprecedented heat wave in summer 2016, average and maximum temperatures compared to the normal $0.9-1.6^{\circ}C$, $0.9-2.2^{\circ}C$ higher incidence was observed in the issues of society during July and August. In the case of the city center, as the heat of the daytime is stored in the ground, it does not evaporate normally by dust, lack of greenery and waterfronts led to the heat island phenomenon. Thus, a cool-roof way to reduce the urban heat island phenomenon is getting attention. A cool roof is a method to lower the temperature of the roof surface by increasing the emissivity and solar reflectance. Reduced heat entering the interior roof surface temperature is lowered and helps to reduce summertime indoor temperature. In addition, it is also effective on urban tropical nights mitigated by reducing nighttime heat emitted by the heat storage structure. In this study the effect before and after by installing a cool roof to the actual building will be observed. The subjects measured where surface temperature, room temperature at the same time and environment at the Gangnam Community Health Center by installing a cool roof on 34% of the whole roof surfaces, located in Gangnam, Seoul. Measurement results show that the surface temperature of the roof construction is effective up to $12.9^{\circ}C$ reduced measurement period during the summer months, while indoor room temperature showed a difference of up to $-1.46^{\circ}C$. In winter, the cool roof room's average indoor temperature differences are $-0.17^{\circ}C$ and 31% of the days were warmer compared with the uninstalled room. So the result shows that the cool roof did not significantly effects on increasing the heating load. In order to expand the cool roof enhanced reliability through various case analyses, form and scale, the form of a roof on a building should precede and be reviewed for a variety of environment-friendly techniques and applying green roof, cool roof and solar to be made in accordance with the conditions of the building.