Green roofs and their contribution for the reduction of room temperature in buildings in Cascavel-State Parana/green roofs and energy efficiency

The objective of this study was to analyze a green roof by monitoring the variables that can influence it, comparing its effects to those of a conventional roof with clay tiles in Cascavel/State Parana. The following parameters were compared in both prototypes: indoor temperature, outdoor temperature, relative humidity, wind speed and solar radiation. Temperature measurements were determined by sensors installed in the prototypes whereas the relative humidity was analyzed by wet bulb sensors. Data concerning to 30 days of experiment were collected and tabulated in Microsoft Excel. The green roof remained for 7 days within the relative humidity range considered comfortable whereas the conventional roof remained for 4 days. The green roof caused a mean reduction of 4.96 degrees C, proving that green roofs contribute to reducing indoor room temperature and thermal lag promoted by the green cover, where the heat input takes longer to occur when compared to the conventional roof. Regarding the behavior of the vegetation cover and substrate, the larger the green cover, the lower the substrate temperature transmitted to the indoor environment.