The apartment buildings now cover more than 50% of the total residential types in Korea and the urban residential area becomes increasingly congested with newly constructed high-rise apartment buildings. Disputes are increasing, however, on infringed solar rights for the neighbouring structures as cases occur where the requirement cannot be satisfied in congested residential areas. So, Korean Building Code restricts 1) the building-to-land ratio 2) floor space 3) height limit and so on. Especially judicial precedents requires, for securing the solar rights in the residential area, that the consecutive sunshine duration should be at least two hours from 9:00 to 15:00 or the accumulative sunshine duration should be at least four hours from 8:00 to 16:00 as of the winter solstice. The objective of this study is to analyze the sunshine duration, to classify according to building type, shape and height from case studies and to provide the reasonable daylight assessment method and code.