Green roofs (GR) are a biomimicry technology which may contribute to achievement of 7 of the 16 Swedish Environmental Quality Criteria. However, GR design is still immature. World-wide often simple structures with Sedum monocultures are delivered, neglecting the challenges GRs face e.g. in demanding climates, thus leading to sub-optimal performance. We hypothesise that more intelligent designs can enhance GR performance.
Thus, we will evaluate the function of standard Sedum GRs in demanding climates. Using 4 field sites in sub-arctic and 4 sites in dry Mediterranean climate, we will identify potentials for performance improvements (WP1) focusing on urban hydrology and energy performance. In parallel, we will select alternative vegetation for GRs, applying the new concept of ecosystem mimicry (habitat templates and plant traits from ecosystems with similar features as GR). These designs will be tested in laboratory (WP2) and the results be verified in field (WP3). We will test if this ecosystem mimicry concept is internationally applicable and support decision making by modelling thermal and water balance.
Due to the cool climate, better adaptation of GRs to demanding climates is important for their use in Sweden. Thus, this research helps to achieve good environmental status and sustainable, liveable cities. The project is also of economic significance since more advanced designs will enable the rapidly growing GR industry to deliver functioning and adaptable solutions.
This project is carried out in collaboration with Construction Engineering and Management, LTU, and the Centre For Urban Horticulture, University of Melbourne.