TOP^ summit

The afternoon of our Knowledge Day existed of the TOP^ summit, on developing the layered city. A co-production of Rotterdamse Dakendagen and AIR (Architecture Institute Rotterdam).

Cities will grow in terms of population, while space is scarce. How do we organize, design and use the limited space in a qualitative, sustainable and inclusive way? What innovations are needed – from rooftop to ground level – to exploit the potential? These were questions we addressed this afternoon.

In March and April, a series of four online expert meetings took place to explore this broad subject (you can find the reports & podcasts of these meetings here). During the TOP^, we explored the subject further. Together with international peers, we exchanged knowledge and work on a manifesto: a call to action and a set of strategic tools and principles to move forward from here. 

Afternoon programme


With Sophie Stravens, host of the afternoon. The opening guests are Barbara Luns, director of AIR (Architecture Institute Rotterdam), and Léon van Geest, director of Rotterdamse Dakendagen.

14.10 – Opening Manifesto by Winy Maas

Winy Maas (MVRDV) will open the TOP^ with his vision on densification of the city as a start of the manifesto. Space is scarce, while there is plenty of space in the air. What is needed to make better use of this ‘new’ space in the city? Are questions he will address. During the dialogues, and presentations in the following two hours, professional from Rotterdam and their international colleagues reflect, elaborate and add on this vision.

14:15 – Start parallel sessions

Participants are invited to follow one of the parallel sessions that will start after the manifesto. Parallel session 1 contains a series of international dialogues between Rotterdam based and international guests. Parallel session 2 contains a programme of 8 short presentations of local, national and international projects on and about rooftops or other subjects related and inspiring to the layered sustainable city.

Parallel session 1: International Dialogues

14:15 – Urban Strategies and Policy of Hamburg & Rotterdam
Guests: Mattijs van Ruijven (head Urban Planning, Municipality of Rotterdam) & Tobias Goevert  (director Regional & Urban Development, Freie Und Hansestadt Hamburg)

Mattijs van Ruijven (head Urban Planning, Municipality of Rotterdam) and Tobias Goevert  (director Regional & Urban Development, Freie Und Hansestadt Hamburg) will explore and define the densification of the city. What are the urban design strategies of both Hamburg and Rotterdam? What urban planning instruments do they use? What are the possibilities to activate or build on rooftop surfaces? What can they learn from each other?

14:45 From railroad to park | Hofbogenpark & High Line Park
Guests: Dirk van Peijpe (De Urbanisten, head designer of Hofbogenpark, Rotterdam) & Robert Hammond (co-founder and executive director of Friends of the High Line – High Line Park, New York City)

How to transform a former railroad in the middle of the city to an attractive park for all citizens? Dirk van Peijpe, designer of Rotterdam’s Hofbogenpark will go into conversation with Robert Hammond, co-founder and executive director of Friends of the High Line (New York City). What are the similarities and differences between Rotterdam’s Hofbogenpark and the famous High Line Park in New York City? How do you deal with ownership and how do you involve local residents in such a development, in the middle of the city? Both successes and risks will be discussed. 

15:15 The possibilities of Air rights
Guests: Erwin Heurkens (TU Delft, assistant professor in Urban Development Management) & Stefan Al (architect, urban designer and founder of Stefan Al Architects, New York City)

Space in city centres is scarce, but the air above is not. Can we find win-win opportunities, to obtain public buy-in for building on rooftops in exchange for better developments at the public scale? This is already an established standard in New York City. Erwin Heurkens (TU Delft) and New York based architect and urban designer Stefan Al will discuss the possibilities and limitations of Air Rights as an instrument for the developments of Rotterdam rooftops.

15:45 Architectural innovation
Guests: Winy Maas (MVRDV) & Eran Chen (ODA)

Eran Chen (ODA) and Winy Maas (MVRDV) are both visionary architects aiming for architectural innovation, fresh typologies and spatial renewings. Eran Chen recently wrote “Unboxing NY” about the way New York City has built up in new layers over the past 10 years. Winy Maas published the MVRDV “rooftop catalogus” on how to make better use of the rooftop landscape. Together they will talk about their experiences in and vision on crafting an intelligent, inclusive and sustainable layered city.

Parallel session 2: Project presentations

14:15 Sanne van Manen (MVRDV) – Rooftop catalogue
Thursday June 3rd, the ‘rooftop catalogue’ of MVRDV is launched. It gives a comprehensive overview of the possibilities of the rooftoplandscape. Sanne van Manen will give a short explanation, a preview of the content and how to use the catalogue.

14:30 Jakob Steen Christensen (JAJA Architects) – PARK’N’PLAY
Konditaget Lüders aka. “PARK’N’PLAY” is a hybrid structure between a parking house and a playground located on the rooftop, 24 meter above ground level. It rethinks the monofunctional parking house and transforms what is often an infrastructural necessity into a public amenity.

14:45 Irma van Oort (KCAP) – urban area development for long-term viability
Irma van Oort, partner of KCAP, will elaborate upon qualitative, inclusive and sustainable urban area development for long-term viability of the layered city. KCAP is a leading international design firm – known for the development of sustainable urban living environments, with buildings and public spaces that enliven and renew the city. 

15:00 Jolijn Posma/Douwe Fischer (Arcadis) & Paul van Roosmalen/Marloes Gout (Municipality of Rotterdam) – Roof valuation tool / Launch
The official launch of a new tool! Arcadis, together with the municipality of Rotterdam developed a tool that calculates the financial, ecological and social value of rooftops. It has already been used for the development of the rooftop of De Doelen. How does it work and who can use it? Come and see.

15:15 Kristian Koreman (ZUS) – Tree House; high rise in wood
How to build high rise in a sustainable way? A 140m tall tower will rise next to Central Station Rotterdam; ‘Tree House’  is inspired by the ecosystem of a tree. The largely wooden building functions as a CO2 collector. How does this project set an example and what lessons can be learned for future sustainable development?

15:30 Caro van de Venne (Barcode Architects) – The Muse / CasaNova
How can we shape the skyline of the city, on multiple layers? CasaNova and The Muse are two residential high rise buildings within the city centre of Rotterdam that are designed in symbiosis with each other. The two towers share a 1.600 square meter lush green fifth-level roof garden, where residents can meet, share a drink and enjoy the view. Together, the coupled towers offer an urban living experience with both privacy and spaces for socialization. The sculptural silhouette of The Muse and the triangular shape of CasaNova are a refreshingly new addition to Rotterdam’s cityscape.

15:45 Helen Toxopeus (Erasmus University Rotterdam) – NATURVATION
Helen Toxopeus (Erasmus University Rotterdam) will elaborate on her work on the EU project “NATURVATION”. She analyses financing and business models of ecological urban innovation (“nature-based urban innovation”). 16:00 Jacques Ferrier (Ferrier Marchetti Studio) – Porte des Ternes, Paris 2022This Paris project offers a unique opportunity to transform the Metropolis at a dense and highly functional urban node. It is a new multi-layered, landscaped structure with green roofs connected by bridges, to create an urban farm dedicated to growing the first crop of Parisian tea. Shared Pavilions enable the occupants and of housing and offices to take advantage of this extraordinary garden. With the planted balconies and the landscape-bridge, the system in 3D as a whole plays the role of environmental machine, contributing to the pleasure of living together in a different way in the city.

16:15 – Closing statements 

With Léon van Geest, Barbara Luns and Winy Maas

16:30 – End of the programme