Program Knowledgeday

A Wider Perspective during the Knowledge Day of Rotterdamse Dakendagen

Introductie (NL)

De afgelopen jaren hebben we tijdens de Kennisdag geleerd over de mogelijkheden van onze daken en het belang van het gebruik van deze onderbenutte ‘bovenstad’. Nu is het tijd om onze kennis in breder perspectief te plaatsen en onze blik over de grenzen te richten. We kunnen met de groeiende internationalisering van Rotterdam natuurlijk niet stil blijven staan en gaan daarom in 2019 met de Rotterdamse Dakendagen international! De Kennisdag – vanaf nu de Knowledge Day – is dit jaar volledig Engelstalig en ook het Dakendagen programma wordt helemaal tweetalig gecommuniceerd. Vanaf nu verder in het Engels!

A Wider Perspective (EN)

Over the last four years, the Knowledge Day of the Rotterdamse Dakendagenhas taught us about opportunities in utilising our rooftops and we witnessed the first entrepreneurs developing daring and innovative projects in the ’second layer’ of our Dutch cities. As we move on from this incubation phase it is time to take a look at what is happening across our borders, to determine the next step in combatting the densification of urban areas in the Netherlands. The complete programme of speakers and workshops of the Knowledge Day is now revealed. Read on for an overview of all keyote speakers and workshops. Block Friday the 31st of May from 12:00 in your calendar for this inspiring Knowledge day!


A wider perspective demands an international speaker programme. This year, we give the stage to architects, urban planners and other (green) rooftop specialists from around the globe who will present their vision on city densification and the development of a sustainable rooftop landscape.

We are happy to announce Winy Maas, co-founder of international architecture firm MVRDV and director of the Why Factory, a research institute at TU Delft for future cities, as one of our keynote speakers. Maas will present his vision on a second layer on top of Rotterdam. Together with the Rotterdamse Dakendagen, he is currently working on the realisation of new structural connections between rooftops of Rotterdam to give them a new function to the citizens. What are the consequences of ownership, safety and precarious rights of this extension of the rooftop landscape?

Furthermore, we have Martin Barry of reSITE on stage; a global non-profit organisation acting to improve the urban environment that wants you to be inspired to reTHINK, reLEARN, reIMAGINE, reDO the city landscape. Keynote speaker Jason Hilgefort, Founder of Land Civilization Compositions and Director of FUTURE+ Academy of Urbanism in Shenzhen, will tell us about the totally different approach Chinese cities have on using their roofscape.

Dusty Gedge (UK), chairman of the European Federation of Green Roof & Wall Association will talk about biodiversity on green roofs; and we have Yim Hyun-Jun Seoul on stage, Manager planning team of the Seoul Innovation Park, he’s responsible for the Rooftop Common Land Project in the Seoul Innovation Park and tells the audience all about this special Korean project of sharing rooftops.

Half-way the plenary session, during lunch, we’ll split up in smaller workshop groups to discuss specific topics in depth. Each workshop is chaired by an international and a Dutch expert to connect international themes to local cases. We’ll have people from the cities of Milan, Lyon, Faro, Nicosia, Prague and Antwerp. Workshop topics and the complete speakers programme will be announced at the end of April. The day will be concluded with the award ceremony of the Dakheld (Rooftop Hero), a prize for the most valuable, recent Dutch rooftop contribution.

We invite all rooftop professionals and other city makers to join our inspiring and innovative Knowledge Day on May 31, 2019 at Kriterion (on top of Groot Handelsgebouw) in Rotterdam! Read on for the full program of speakers and workshops!

Keynote speakers

Sereh Mandias Rotterdam, Netherlands
Rotterdamse Dakendagen asked architecture critic Sereh Mandias (TU Delft) to write an essay about the use of rooftops throughout history from an architecture-historical point of view. She will share the result in an opening speech. Participants will also receive the essay as a booklet. From Mesopotamia and the hanging gardens of Babylon to Le Corbusier and the current position of rooftops.

Jason Hilgefort US/China
Jason Hilgefort is Founder and director of Land Civilization Compositions and director of FUTURE+ Academy of Urbanism, Landscape and Public Art in Shenzhen. Jason studied Urbanism and Design at the University of Cincinnati and Architecture at the University of British Columbia in Vancouver. His working experience reaches from New York and LA to Mumbai and Rotterdam. Over the last four years he primarily worked in Asia. Jason advocates small scale roof adaptations in the light of densification, instead of ‘corporate gestures’ and ‘design exercise’. During his keynote, he will tell us about the totally different approach Chinese cities have on using their roofscape. He will take lessons from Asian metropoles to a continuously developing Rotterdam.

Martin Barry Czech Republic / US
Martin Barry is director of reSITE, a global non-profit organisation acting to improve the urban environment and wants you to be inspired to reTHINK, reLEARN, reIMAGINE, reDO the city landscape. Martin tells about his keynote: “reSITE was started because I wanted to listen closer. And, I was growing tired of what is known as a classic architecture, landscape or urban design firm. I wanted – and still want – to push my own limits in this respect. At first, it was a selfish endeavour. I had an idea, some time, and wanted to work with interesting people with different professional and cultural backgrounds. I wanted to see how useful we can be in the making of a city by providing new insight with a start-up mentality, without profit in mind. I wanted to see if we could create links between professional groups or ideas where other people didn’t see them. Now it is a much bigger mission. What we found is that we can and are doing all of that. And, we can do more. We can remake the city if we listen to people, help them design the problem – and help them act. I try to create an environment at reSITE where we define new limits every day, we inspire each other, and where everyone feels comfortable to expand and grow. We define the best project or event, then we go and figure out how to fund it. We always start with ‘it’s possible,’ and never begin with ‘no’.”

Winy Maas Rotterdam, NL
Winy Maas is co-founder of international architecture office MVRDV and member of the recommendations committee of Rotterdamse Dakendagen. Furthermore, Winy is also director of The Why Factory (TWF) at Technical University Delft. TWF is a research instiute for future cities founded in 2008. Since 2013 he is visiting professor at the University of Hong Kong. Recently, Winy became member of the Economic Development Board of Rotterdam (EDBR). With both MVRDV and TWF he published a series of research projects about the future of cities. In 2016 MVRDV realised De Trap (The Stairs) leading to the rooftop of Groot Handelsgebouw, which was climbed by 300.000 people within a month. Ever since, he fantasized about rooftop connections in Rotterdam. Now he is working together with the Dakendagen to realize the first real rooftop connections. During his keynote, he will talk about the consequences, like ownership, safety and precarious rights, of this new extension of the rooftop landscape.

Dusty Gedge London, UK
Dusty Gedge is chairman of the European Federation of Green Roof & Wall Assoc. During his keynote he will talk about biodiversity on green roofs. Dusty is an expert in the field of green roofs and ecosystem services. For over 15 years, he is involved with ground breaking projects concerning urban biodiversity and mainly concerning green rooftops. He wrote the book ‘The nature of cities’ and he favours diverse vegetation in cities for adaptation to climate change.  Rooftops offer space fort his vegetation. With his broad network and experience, he has many examples of inspiring and adaptable projects

Marina Kyriakou Nicosia, Cyprus
Maria Kyriakou is an urbanist, researcher and member of the Urban Gorillas. Marina finished her master urbanism in The Netherlands and is currently developing plans to use rooftops as a counterweight for the wall that splits her city Nicosia (Cyprus) in two parts. By not removing the wall but creating a new layer on top of it, she connects the two communities that live here.

Friso Klapwijk Utrecht, NL
Friso Klapwijk is owner of the Dakdokters (Rooftop Doctors) and Metropolder B.V. After creating over 1500 (!) rooftops in Europe, Dakdokters opened an office in New York City in 2019. He will talk about the journey they make with Dakdokters and the ‘polderdaken’ the company develops.

Jeroen van Swieten Den Haag, NL
Jeroen van Zwieten is Director of Sobolt, for a sustainable future. In 2016 Sobolt started as an AI-tech start-up in Rotterdam. In 2018 Sobolt made a full inventory of the rooftops in Rotterdam by the use of satellite data. What are his discoveries? How will the municipality of Rotterdam handle rooftops in the future? Jeroen will present the research and opportunities.

Renée Miles Rooijmans Rotterdam, NL
Renée Miles Rooijmans is a cultural anthropologist and working for STIPO. She has spent the last year living in a tiny house on a rooftop, ever since that rooftop became public space during Rotterdamse Dakendagen 2018. She’s part of the ‘Dakdorpen’ (rooftop villages) project by Walden Studio, for which she will soon be moving house … to a different rooftop. During this keynote she will explain her vision on the future of residing on rooftops in Rotterdam and around the world.

Yim Hyun-Jun Seoul, Korea
Yim Hyun-Jun is Manager of the planning team of the Seoul Innovation Park, and is responsible for the Rooftop Common Land Project (RCPL). The Rooftop Common Land Project was started at the University of Seoul in 2017. Ever since, 38 programs were formed at 8 rooftops in the city. As part of RCPL the rooftops of the university, for example Future Field, Project Path and Idea Bridge, are transformed into a communal space of 3.200m2. The goal is to create a community at the rooftops. The project aims to transform public spaces to a place for participation, useful for citizens. The use of rooftops as new public social spaces is one of the goals of the Rotterdamse Dakendagen, but is an undervalued aspect in the Netherlands compared to the use of green, water retention and generating energy.


Our Workshops are actually round table conversations, on a roof. We’ve invited international and local experts on a certain rooftop-subject, who are interested in each other and willing to learn. They’re gonna talk about their expertise and you can join them in that conversation.

Rooftop Common Space
With: Yim Hyun Jun (Seoul, Korea. Also keynote speaker), Martin Blaas (Rotterdam, Netherlands) and Gerda Zijlstra (Rotterdam, Netherlands)

Yim Hyun-Jun investigates the use of rooftops as common social spaces in Korea. He will discuss this topic with Martin Blaas and Gerda Zijlstra. Martin works for the green rooftops program of the Rotterdam Municipality and Gerda is founder of Rotterdamse Oogst (Rotterdam harvest).

Private/public roofs
With: Jason Hilgefort (US/China. Also keynote speaker), Emile Arends (Rotterdam, Netherlands) and Pim Bens (Eindhoven, Netherlands)

Jason Hilgefort advocates small scale roof adaptations in the light of densification, instead of ‘corporate gestures’ and ‘design exercise’. He will discuss this topic with Pim Bens and Emile Arends. Emile Arends is spacial advisor city development in Rotterdam and also a teacher Water Management at HRO. Emile is the densification specialist of the municipality of Rotterdam and knows the real estate situation and its (im)possibilities of this city throughout. Pim Bens works for the Technical University of Eindhoven and started the research project ‘Home Made City’ about self-initiated forms of living in Hong Kong.

Starting a European network
With: Bruno Inácio (Faro, Portugal), Cédric Deverchere (France) and Remco Moens (Amsterdam, Netherlands)

Bruno Inácio is Head of Culture of the Municipality of Faro and Founder of the Rooftops4europe network. Graduated in Urban Cities and Cultures at the University of Coimbra (Portugal), Bruno started working for the Faro Town Hall in August 2018. He was involved in organizing the first European Rooftop Meeting in Faro, making a case to use these spaces in an environmentally responsible and sustainable way, and restore them as meeting places for the community. Remco Moens is co-founder and owner of rooftop festival ROEF. Remco co-founded the Amsterdam rooftop festival ROEF, through which he wants to show people that the currently underutilized roofscape has high potential. Cédric Deverchere is an urbanist with great interest in sustainability. These three specialists will start a conversation about starting a European Rooftop Network to create a sustainable future.

Green City Rooftops
With: Paul van Roosmalen (Rotterdam, Netherlands), Sophie Matias (Faro, Portugal) and Inge de Boer (Milan, Italy)

Sophie Matias is counsellor of urbanism and sustainability in Faro and joins this workshop together with Paul van Roosmalen, head of Green Rooftops for the Municipality of Rotterdam and Inge de Boer, a Dutch architect living in Milan which has a special green-rooftop program. Inge started ROOFmatters in this city. For this project she organized various events in Milan to raise awareness about the impact of rooftop gardens and to keep the discussion going and connect people.

Political Rooftops
With: Marina Kyriakou (Nicosia, Cyprus. Also keynote speaker) and Sereh Mandias (opening speech)

Marina Kyriakou is developing plans to use rooftops as a counterweight for the wall that splits her city Nicosia (Cyprus) in two parts. By not removing the wall but creating a new layer on top of it, she connects the two communities that live here. Sereh Mandias will join the conversation as an architecture critic and they will discuss the political aspects of rooftops.

Innovation in Waterretention
With: Friso Klapwijk (Utrecht, Netherlands), Joeri Schenk (Rotterdam, Netherlands), Dirk van Peijpe (Rotterdam, Netherlands), Kaj van der Sandt (Nijmegen, Netherlands)

Friso Klapwijk is owner of Dakdokters (Rooftop Doctors) and Metropolder B.V. After creating over 1500 (!) rooftops in Europe, Dakdokters opened an office in New York City in 2019 to bring Dutch water-innovation to the states. Joeri Schenk is projectleader climate-adaptation at Hoogheemraadschap Schieland and the Krimpenerwaard. Dirk van Peijpe is Founder and director of URBANISTEN an innovative office for urban research, design and landscape. Kaj van der Sandt is head of the Water-management department at the Hogeschool Rotterdam. Together they will have a thorough discussion about all aspects of water(retention) on rooftops.

Stimulating the use of rooftops
With: Greet Nulens (Antwerp, Belgium) and Eveline Bronsdijk (Rotterdam, Netherlands)

Greet Nulens is Spatial Planner and head of “Ecostadprojecten” for the City of Antwerp. Working for the City of Antwerp since 2010, Greet is one of the initiators of the “Climate Robust Roofs” project, challenging and supporting roof-owners to furnish their roofs in a way that is heat-controlling, manages rainwater and supports biodiversity.  Eveline Bronsdijk is project Leader Green Rooftops for the municipality of Rotterdam. Eveline is Working on Urban Development for the City of Rotterdam since 2008, she has worked on sustainability-related projects. This includes green roofs, which are not only important for climate resilience, but also provide new opportunities for recreational activities. A conversation about how to stimulate the use of rooftops.

Living on rooftops
With: Renee Miles (Rotterdam. Netherlands. Also keynote speaker), Laurens van der Wal (Rotterdam, NL) and Martin Barry (Czech Republic/US. Also keynote speaker)

Renee Miles (Rotterdam, NL) is a cultural anthropologist and works for STIPO. As part of a project for the Rotterdamse Dakendagen last few years, he lived on rooftops in a tiny house. Laurens van der Wal is co-owner of Walden Studio, the first studio to come with the idea of a rooftop village. Together with Renee Miles and Rotterdamse Dakendagen, he will realize a rooftop lab this year. The two will be joined by Martin Barry, director of reSITE, a global non-profit organisation acting to improve the urban environment and wants you to be inspired to reTHINK, reLEARN, reIMAGINE, reDO the city landscape. These speakers will discuss the challenges of living on rooftops.

A new rooftop trail
With: Simone Rots (Rotterdam) & Michelle Provoost (Rotterdam)

Simone and Michelle are a part of Crimson Historians and Urbanists and are the founders of the Independent School for the city. They inhabit a beautiful building by Hugh Maaskant, close to the Central Station together with other city-making-related company’s. The dream is to make a Rooftoptrail from their building over 7 roofs (of approx. the same height) to the famous ‘Dakakker’. This workshop will be the kick-off for this project. They’ll take you to the site, and together you will explore the possibilities.

Green Deal green rooftops: national rooftop plan and financial incentives
With: Anne-Marie Bor (Utrecht, Netherlands), Carleen Metsers (Utrecht, Netherlands) and Marloes Gout (Rotterdam)

Anne-Marie Bor (Utrecht, NL) is Project Leader Green Deal on Green Roofs. Anne-Marie has been working in the field of sustainable development and design for over 25 years, both in consulting positions and as a government official. She founded the company NextGreen, which supports businesses in becoming more sustainable. Last year ‘Green deal groene daken’ won the Dakheld (Rooftop hero) during the Rotterdamse Dakendagen. Together with Carleen Metsers she will discuss the pilot for a national rooftop plan, that will be launched this year, and its financial incentives like differentiation taxes.

Big rooftop projects
With: Jeroen de Leeuw (Rotterdam, Netherlands), Jan Henk Tigelaar(Amsterdam, Netherlands)

Jeroen de Leeuw is projectleader of 7 Square Endeavour, an international collaboration and sustainability project with a mission to prepare cities for the future. On a local scale the project anticipates worldwide urbanisation and the adverse consequences of this such as pollution, heat stress and flooding. The rooftops of the Schouwburgplein in Rotterdam act as an experimental area for new innovative technologies, cyclical processes and business models.
Jan Henk Tigelaar is director of the Amsterdam based Rooftop Revolution, an initiative to bring back nature in cities, and in that way help with climate adaptation. They participate in the European funded RESILIO-project, in which 10.000 m2 of smart blue-green roofs will cover social rental housing in 4 areas in Amsterdam.
Jan Henk and Jeroen will discuss the successen and the setbacks they encounter in these projects.

Biodiversity NL/UK
With: Dusty Gedge (also keynote speaker), Rens de Boer Rotterdam, Netherlands) and Dymphie Brouwer (Netherlands)

Dusty Gedge is chairman of the European Federation of Green Roof & Wall Association. Together with Rens de Boer of Bureau Stadsnatuur (Bureau of City Nature) and Dymphie Brouwer, researcher of the Rotterdam ‘Stadskip’ (city chicken), they will dive into the topic of flora and fauna on rooftops. Recently, a new wasp species of insects was discovered on rooftops in the Netherlands! Curious to the research? Join this this workshop.

Rooftop Data
With: Jeroen van Swieten (Rotterdam, also key-note speaker) and Roel Pronk (The Hague, Netherlands)

Jeroen van Swieten is Director of Sobolt, Energy Intelligence. In 2019 Sobolt started to make an inventory of the rooftops in Rotterdam by the use of drones. This provides valuable data for rooftop usage. Roel Pronk van Novasole, Solar Engineers uses rooftopdata to provide customers with quick scans for the potential of their roofs.

Practical information

Date: Friday 31st of May 2019 from 12:00 until 17:00 + drinks until 18:00
Location: Kriterion (7th floor Groot Handelsgebouw), Stationsplein 45

Overview programme:
12:00 Opening by Léon van Geest en Bas Kurvers & opening speech
12:10 Start keynotes
13:00 Lunch & Workshops
15:00 2nd part keynotes & handing out the Rooftop Hero prize
17:00 Network drinks

The visit of Dusty Gedge and Yim Hyun-Jun is made possible by the Het Nieuwe Instituut with support of the Dutch Ministry of Foreign Affairs.