Establishment of catchment coefficient using wall surface in slenderness ratio-specific miniature models created for experiments

This study aimed to assess the efficiency in collecting rainwater by utilizing the surface of walls in building structures, as part of the efforts to expand the application of rainwater utilization. Walls of building structures, in particular, have the merits of securing high-quality rainwater simply by precipitating the water via similar material that is used in roof surface for rainwater collection. The buildings wherein rainwater utilization facilities are installed in roof surfaces have the merit that allow the shared use of rainwater without having to install any further systems other than the collecting system. Given the aforesaid, this study attempted to assess and verify the efficiency of rainwater collecting systems that are applied to the surface of walls in building structures. To this end, miniature models were created for the typical intra-city buildings wherein installation of rainwater utilization facilities/systems is recommended by the Water Act. During the experiments, factors for calculating the amount of catchment were controlled and then the surface of walls was exposed to actual rainfalls to calculate the coefficient of catchment via wall surface as influenced by wind velocity. Results of the study include the establishment of a formula for catchment coefficient for each slenderness ratio (model) via linear equation. Additionally, implications were proposed for additional studies to ensure future research in this area.