Vertical greening in urban areas

More and more people are living in cities. Accompanying symptoms include air pollution from traffic and high noise levels. Appropriate solutions are needed to ensure a high quality of life and to further optimize it: Increasingly, the greening of urban space and urban infrastructures is becoming the focus of architecture, planning and construction. On the one hand, there is a desire to use green spaces as a design element; on the other hand, greening is expected to have a positive impact on oxygen production, CO₂ binding and air pollution control. In addition, there are potential energy savings and positive effects on the microclimate, due to the insulating and cooling effect of planted areas, as well as positive effects on biodiversity through the creation of new habitats.

Together with partners, Fraunhofer UMSICHT has developed special elements based on a mineral material (sand-lime brick) for the construction of green walls. The mineral material is ideally suited for such applications due to its optimized absorbent and liquid-storing properties. The individual elements are provided with planting gutters and are installed to form a modular system. The gutters are filled with planting substrates and can then be sown or planted. The plants grow forward out of the structural elements and cover the vertical surface. A wide variety of plant species are suitable for greening, depending on the type of greening desired. Grasses in particular achieve greening success after just 2 to 3 weeks.

Irrigation is from above, and due to the liquid transport properties of the stone, the water in the wall is directed downwards by gravity alone, reaching all the planting troughs. This significantly reduces the effort required to care for the plants. If necessary, individual stone layers can also be watered separately.

By using individual construction elements, the system is scalable so that areas of any size can be created. The areas of application range from wall cladding and greening to use as a design element or greened partition wall to vertical gardening. Small modules can already be used in the size range of balconies or terraces for planting or as herb gardens.

Due to their design, the components enable economical and industrial production in series. So far, pilot systems have been installed in Castrop-Rauxel (UNIKA), in Orihuela Costa (biolit) in Spain and in Oberhausen (Fraunhofer UMSICHT) for research purposes – with convincing practical results. Measurements of the noise protection behavior recently completed confirm the system's excellent values.

In subsequent work, Fraunhofer UMSICHT accompanies the realization of greening objects. The focus here is in particular on investigations of the behavior of the system with regard to microclimate improvement and cooling effect in urban areas.

• Biolit Vertical Green^®
• UNIKA – Ruhrbaustoffwerke GmbH & Co. KG