Abstract
Recently, the apartment building has been constructed in large quantities to provide housings due to the gravitation of population towards large cities. However, we're faced with a critical problem of deterioration of our dwelling environment caused by the trend toward high-rise apartment which could be an obstruction in obtaining sufficient sunlight. Therefore, there have been several legislative actions against infringement on the right of sunshine. In the building law, sunshine hours and the minimal separated distance between apartments are regulated as the criteria for the site planning, However, the minimal separated distance was defined without consideration of the parameters like building orientation and thermal effect of the sunshine hours in the site planning for the apartment building. In this study, the sunshine hours and heating energy during the underheated season for various arrangements in site planning are carefully considered and analyzed.