PACIFIC NORTHWESTERN EXPOSURE: A LONG-TERM STUDY OF PACIFIC NORTHWEST CLIMATE ON EXTENSIVE GREEN ROOF PERFORMANCE IN PORTLAND,OREGON

摘要

The exposure of a green roof to regional and local climate and weather can have a profound impact on the performance of that roof system. Climate can influence thermal performance, physical properties, and hydrological function of the roof assembly. This study proposes a classification system for exposure of green roof systems. Analysis was performed on two roofs in three different exposure categories to determine the extent of climatic and weather effects on the roof. Weather stations were installed on functioning green roofs and monitored for a full year. Data was analyzed for three different seasonal periods from the test year. Exposure category I (fully exposed roof and parapet >1') was shown to be the best performing condition for stormwater discharge with an average delay between two and seven days. Exposure category I was also shown to be 3% - 11% more thermally stable during the majority of a year.