Lee and Simon spent a couple of days last week in Stuttgart and the surrounding area at the invitation of Optigreen, whose team showed us around the #greenroof capital of Europe. It was phenomenally inspiring vision of how cities will be designed in the future.
Almost every flat roof in the city-centre sports a mature green roof. Predominantly sedum, there are also multiple intensive green roofs on many of the downtown commercial premises.
Sitting in a natural bowl, the city nestles between vineyards and thick woodland close to the River Neckar. This geography has played a central role in the city authorities mandating of green roofs – to manage the rainfall enterging the sewer system, for 20 years or more there has been a requirement for the city’s green roofs to retain 70% of the rainfall that hits them.
The Optigreen Meander Board was developed in part to help meet this ambitious target. An innovative product that permanently stores up to 16L/m2 of rainwater and slowly discharges the rest, we are excited to build this into our standard specification – building on the ecological enhancement approach to green roofs that we already take by thinking about water-sensitive design.
It is not only for rain, however, that Stuttgart is known – enjoying hot summer months, local residents refer to this area as the Stuttgarter Kessel, or the Stuttgart cauldron, with its hot and humid climate frequently warmer than the surrounding countryside of Württemberg. In these conditions the added thermal mass of green roofs also helps to reduce a building’s energy input: the electricity needed to power air-conditioning units in the buildings below can be reduced significantly, as shown in this recent report to which we contributed on on the huge potential for green infrastructure to improve the economy and environment of our home town, Brighton.
The picture above shows part of a rooftop park above a shopping centre in the town, an amenity green roof with bar and recreation area open all day and evening for residents and shoppers. We were also taken to a roof above a health centre which features a small running track for physiotherapy patients to use for rehabilitation (and Zak from Watermatic Ltd to practice his upcycling!)
The two day visit gave us the chance to strengthen our working relationship with Optigreen, Europe’s largest supplier of high-quality green roof elements, and we’re very much looking forward to working together with ‘the BMW of green roofs’ in the year ahead.