Driving rain, the rain carried by the wind with a horizontal wind speed component, is a major humidity source affecting the durability and hygrothermal performance of building façades. The article presents an assessment of driving rain exposure level in Florianópolis-SC, using driving rain indices and driving rain wall indices. In order to obtain these indices, semi-empirical formulas from the international literature on driving rain as well as wind speed, wind direction and rainfall data from meteorological stations in Santa Catarina Island and the neighboring city of São José were applied. The analysis covered three periods: (a) 1961-1970, (b) 1991, 1993-1996, and (c) from September 2005 to August 2006. The analysis revealed that the exposure level of the area investigated varied from moderate to high, with the southeast, south and southwest being the most critical directions for driving rain exposure. The results of this investigation provided information that is useful for the design of building façades within that area and may contribute to increase the knowledge on durability and thermal comfort.
Driving rain; Driving rain index; Façade; Building; Durability; Thermal comfort
