The vision of climate-neutral cities for 2030 requires, among other things, new solutions for the construction industry. Green roofs are an important part of the green strategies and solutions that have emerged to increase biodiversity and meet climate change in cities.
In recent weeks, large amounts of rain have fallen over the Gävle area and stormwater management is an extremely important issue. The vision of climate-neutral cities in 2030 requires, among other things, new solutions for the construction industry. Green roofs are part of the green strategies and solutions that have emerged to increase biodiversity and meet climate change in cities. A major advantage of green roofs is the water-holding capacity that can relieve stormwater systems by both delaying and storing rainwater.
The strategic innovation project “One roof – five opportunities” explored issues related to the implementation of green roofs in urban areas. The project was coordinated by FPX and operated within the strategic innovation program Viable Cities, funded by Vinnova, the Swedish Energy Agency and Formas.
We have talked to three people involved in the project, Henrik Dahl, CEO of FPX, Agneta Persson, Anthesis, and Marita Wallhagen, associate professor of environmental science at the University of Gävle, about their views on green roofs.
– When FPX carried out this project we did not realize how relevant it would be for Sweden and for Gävle in particular. Now with more relevant knowledge we can take action. A new area to start with in Gävle could be Näringen or the Southern City in Uppsala, says Henrik Dahl.
– The floods that hit Gävle and other European cities recently show that old solutions no longer work and that we must quickly switch to a societal infrastructure that not only counteracts climate change, but actually prevents it, says Agneta Persson.
– For example, green roofs must be a natural part of the new infrastructure. Research shows that our activities drive climate change. The latest IPCC report shows that the risk of flood events increasing in magnitude and frequency is over 66% risk. Green roofs can help counteract and prevent flooding effects. In addition, green roofs can also help stimulate biodiversity and create places for recreation.
Within the project it has become clear that green roofs can provide great values for both property owners and society and contribute to our built environment becoming more environmentally sustainable according to architect Marita Wallhagen.
– The fact that the green roofs can store and delay stormwater is a great advantage. The fact that they also provide ecosystem services, increased biodiversity, can reduce heat effects, positively affect air quality, noise, health and well-being and reduce the buildings’ energy use are some of the positive effects of roofs with vegetation. If we had had more green roofs and a smaller share of paved surfaces in Gävle, a significantly larger share of the record rain would have been taken care of locally. The rainwater had thus not contributed to floods and water-filled basements to the same extent.
Read more about the Green Roofs project