Daylighting Performance Evaluation of a Light Pipe System

There are many environmental problems due to crowded buildings. Since Seoul is the second highest city in population density (16,994 person/ km²). Particularly, the problem of poorish sunshine is the most urgent one. In order to solve the problem of poorish sunshine and provide sufficient daylight in interior spaces, it is necessary to install some effective lighting systems. Among these systems, light pipe system, which is simple, cheep, and easily constructible, is a very useful system for small buildings and houses. The purpose of this study lies in developing and evaluating the daylighting performance of the light pipe systems. In order to do so, we performed model experiments under clear sky conditions. As results, it was testified that the light pipe systems are very useful for small buildings. However, it is necessary to combine artificial lighting systems in order to supplement insufficient daylights. Also, to avoid glare and reduce difference of illumination uniformity, it is recommended to install ceiling diffuser.