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Interview Architecture Public space

From concrete to colour


Words by Lena Bril

Photos by Sophie Wright

From street level, you wouldn’t guess that at the top of soon-to-be-opened Hotel Zoku lies a small haven of green. Jaap de Jong, one of the founders of Rooftop Revolution, looks out over the grey concrete mass in front of us. We are standing on a roof in the middle of Amsterdam, where green contractors De Dakdokters and GrownDownTown are building a rooftop garden. This unique initiative forms a perfect showcase of Rooftop Revolution’s ambition. The workers are running around with plants, soil, herbs and even small trees as Jaap tells us more about their collective mission: to turn an unused roofscape into a colourful nature reserve in the middle of the city.

Can you tell us about yourself?

When I was a little boy, I always wanted to become a forest ranger. The idea of being surrounded by nature was very attractive to me: nature is unpredictable, I’d be able to get up every morning, go to work and have no idea what the day would bring. I didn’t become a forest ranger, although my career has been determined by similar topics such as the environment and sustainable development. I studied Environment & Resource Management and worked for various organisations, both commercial and non-commercial, on sustainable development projects. At the moment, I work as a director of De Gezonde Stad, a non-profit that is devoted to making Amsterdam a healthy and sustainable city with a good quality of life. This is exactly the kind of job that suits me: the organisation is small which makes it much easier to just roll up our sleeves and get to work instead of talking too much about it. This way, we can have measurable impact and really contribute to a healthier city.

How did your combined interest in the city and nature develop?

Over the years, it turned out that I’m a city person. Although I really love nature, I thrive in the city and besides that the city plays a key role in sustainable development. So now I’m trying to bring the forest and nature into the city, which in a way brings me back to my childhood ambition.


How did Rooftop Revolution come about?

More than 12 km2 of flat roofs in Amsterdam are just lying there; grey, ugly and unused. Why don’t we properly use these rooftops? 12 km2; that is almost 25 times Vondelpark, the green heart of the city that’s suffering from its own popularity. Space is getting more and more scarce and expensive, leaving less room for much needed green environments in the city. Together with another non-profit working on sustainable development, De Groene Grachten, we asked ourselves: why are we not looking a little higher off the ground for greener solutions? Our mission for the next few years is to green up at least 10% of the roofs in Amsterdam, to make the city more green, healthy and smart. Our public outreach started with a simple item in our newsletter, and we were overwhelmed by all the reactions we received as a result. Within a day, we had enough participants to commence with our first pilot projects.

Amsterdam has more than 12 km2 of flat rooftops, just lying there, unused.
Photo via rooftoprevolution.nl
Photo via rooftoprevolution.nl

What does Rooftop Revolution offer to all these enthusiasts of roof gardens?

The business case for a green roof is quite complicated. Lots of people benefit from a roof garden, but usually, the property owner bares all of the costs. To make a roofscape that is truly green, we have to collaborate in an innovative manner. Rooftop Revolution brings together the owner of the roof and all other parties who benefit from a green roof. With our support, all stakeholders can develop a specific business case for their situation. We provide them with a crowdfunding and crowdsourcing platform, which allows everyone to contribute to these new natural spaces in the city. Apart from the financing, we also offer a toolkit, which guides the initiators through the entire process from idea to realisation. We also assist the initiator with specific crucial challenges about their roof such as the design and the technical issues. And, of course, advise them how they can mobilise their neighbours.


How can Rooftop Revolution improve urban living?

All people that work and live in the city can potentially benefit from a green roofscape. Especially people that can make use of the roof gardens of course. Research has shown that plants and flowers make us feel more happy, relaxed and healthy. People are using green spaces in the city more intensely, parks and public gardens are more popular than ever. Those public green spaces are now really functioning as gardens for citizens. At these places we meet friends, celebrate our birthdays, exercise. We even use them as outside offices to work. The rooftops could also fulfill this function as a public city garden for recreation, which would take the pressure of our parks a bit. Apart from direct use, a greener city benefits our health. Rooftops filled with flowers and plants clear the air from toxins that we would otherwise inhale. Green roofs also reduce noise pollution. And they literally cool the city, where temperatures can be up to 8 degrees higher than in surrounding areas, mainly caused by constructed surfaces in the city and a lack of green and open spaces. These higher temperatures can be bad for your health, especially for children and elderly people. Rooftop vegetation has a significant and positive effect on this!

How does the city benefit from green rooftops?

Having more green and less concrete has many advantages for the city, from both a health and environmental perspective. Plants and flowers are perfect isolation material, especially in summer when we use air conditioning to cool our buildings. These can be turned off more often in a greener city, also because flowers and plants naturally cool down the atmosphere. And that’s not all. Climates are changing and cities like Amsterdam will face more extreme rainstorms. Rooftops filled with soil and plants are perfectly capable of absorbing all that water and slowly releasing it to the sewer system. This reduces damage caused by heavy rainfall. Additionally, roof gardens have a positive effect on property values. You can safely say that it is ridiculous that we don’t do more to green our rooftops.

Green rooftops help solve the challenges that cities face.

How do you see the future of the city?

I see a green future! The integration of nature into urban areas will continue. More and more buildings are designed or refitted with prominent green aspects. The sense of urgency for project developers and policy-makers to integrate nature into urban areas is increasing. It is especially interesting to see how nature organisations that traditionally focus on areas outside the city are also shifting their attention to urban areas. We see the same developments in other big cities such as Paris. I also see great potential in growing our own food on roof gardens and new techniques will make this possible even on a bigger scale. For Rooftop Revolution, we will help other cities in the Netherlands and beyond with making rooftop gardens. My wildest dream? That would be to realise a project like New York’s High Line in Amsterdam.