The green roof movement

By Emma Peterson. 

From lowering urban heat to managing stormwater, learn about why people around the world are incorporating green roofing.  

On the whole, there has been a distinct rise in interest in green roofing around the world. Especially in countries abroad, like Germany, it is more common to see a new roof have vegetation on it than not. To learn more about this growing market, Heidi J. Ellsworth hosted John Parker, a landscape architect and member of the Furbish green roofing team, and Angie Durhman, a technical sales rep for SOPREMA who focuses on the green roofing market and comes from a horticulture background, for an episode of CoatingsTalk. 

In general, the rise of green roofing can be attributed to the many different benefits that come with it. Angie shared one, saying, “There are so many benefits. For one, when you put vegetation in an area, it automatically reduces the urban heat island effect anywhere from 3-10 degrees. Think about walking through a park with tree canopy and other garden areas, you're going to have a more pleasant experience walking through that space because those plants release water vapor that cools down the area.”  

Another example of a benefit comes with storm and rainwater management to help cities avoid flooding. Angie explained, “With a green roof, we're saving somewhere between 70% to 90% of the water from rain events on the rooftop or in the garden areas around the building. When we get to save and retain that, we're able to relieve some of the pressure on that existing stormwater infrastructure that was probably built 80-90 years ago.” 

These are just two of the many benefits that come with green roofing. So why aren’t green roofs everywhere? John shared his thoughts, saying, “I think local governments are a little bit anxious about saying you have to build a green roof if you want a building permit because no one likes being told what to do. But we can look abroad to places like Germany, which has maybe a hundred times more green roofs than we do here, to see what they’re doing.”  

When it comes to green roofing in Germany, they don’t have any requirements for green roofing to get building permits. Instead, they look at the benefits, like stormwater management, and charge people for the service. John explained, “They tell people, 'You can either put a green roof on your building or we're going to charge you 50 euros a square meter per month for stormwater management.’ So very quickly, people do the math and choose to put the green roof on without anyone telling them they have to in order to build.”  

Angie added her thoughts on how this model could be translated to the domestic market, saying, “I think we need to look at our regions and the costs we could be offsetting with green roofing. Then we need to start incentivizing green roofing until we get to a point like Germany, where it’s pretty unheard of to have a new build without a green roof.” 

Read the transcript, Listen to the episode or Watch the recording to hear more from John and Angie about the rise of green roofing.