The master thesis deals with performance of extensive green roofs on rainwater runoff quantity in three different climates typical for Slovenia (continental, submediterranean and mountain). The measurements were done on three different test green roofs. The data were used for rainwater runoff modelling. The results showed the response of three different roofs in three different climates. We have found that the reduction of rainwater runoff depends on
the rate of evapotranspiration in the area and on the green roof evapotranspiration coefficient. It is reasonable to increase the retention capacity only for green roofs with high evapotranspiration coefficient in climates with high rate of evapotranspiration. Increasing the retention of green roof in climates with low evapotranspiration does not always result in runoff attenuation. Based on the findings, we proposed the conceptual design of the blue-green roof which is suitable for all three climate types of our research.