Green roofs — an important component of the German adaptation strategy to climate change — can contribute to improving the thermal environment in urban areas, with the cooling effect through evapotranspiration being an important aspect. But the use of this evapotranspiration capacity during longer periods of drought and heat is severely restricted by limited retention capacity of the frequently used low-layered forms of green roofs. While this can be counteracted by increasing the layer structure and supplementary irrigation, for reasons of sustainability and economy the use of drinking water is not practical.
An interdisciplinary research project started in December 2019 at TU Dresden is investigating the possibilities and challenges of irrigation with treated grey water. The results should provide information about the extent of the effect of irrigation on the retention capacity, the evapotranspiration potential, and the building climate as well as the appearance of green roofs with simple intensive greening.
Prof. Irene Lohaus, Chair of Landscape Architecture at the Institute for Landscape Architecture at TU Dresden, will discuss “Integrated Rainwater Management for Green Roofs” at the 16 November session of the joint UNU-FLORES and TU Dresden Nexus Seminar Series.
For more, or to register to participate, see the seminar announcement on the UNU-FLORES website.