Roofscapes

DE URBANISTEN constructed a comprehensive perspective for the Rotterdam roofscape; from a rich and diverse use of roofs in the city center with roof parks, event spaces, sport fields etc. to extensive solar farms and ecological roofs in the harbor and from modest private initiatives for single roofs in suburbia to collective functional programs in the post war garden city.

The Rotterdam roofscape provides an impressive abundance of space: 14.5 km2 of flat roofs. It’s the result of a tumultuous history of the city. This roofscape waits to be further explored and developed. The Rotterdam municipality wants to encourage ‘sustainable roofs’ and asked De Urbanisten to examine the conditions for the multifunctional use of rooftops in the city and to visualize the potential of the Rotterdam roofscape.

All the roofs of the city – from very high to low, from large to small and flat or inclined – offer different opportunities to add value to both the owners/users and the city. We categorized 4 roof ‘colors’: Green vegetated roofs; Blue roofs to buffer rainwater; Yellow roofs that generate sustainable energy; Red roofs that are actively usable for people. The purpose is to find the right mix of colors that suits the type of roof, its physical context and users. Therefore we define parameters for possible rooftop uses. Specifying shape, construction, size, accessibility, height, urban density, physical and political context, in order to be more precise on the optimal relation between its conditions and possible uses. We link our results to five different Rotterdam city typologies, varying from the compact inner city to the post-war districts and the harbour. We identify the most fit roofscapes for each type of district and thereby offer a more nuanced view on the nowadays fashionable exorbitant greenwashing of roofscapes.

Ultimately we constructed a comprehensive perspective for the Rotterdam roofscape; from a rich and diverse use of roofs in the centre with roof parks, event spaces, sport fields etc. to extensive solar farms and ecological roofs in the harbour and from modest private initiatives for single roofs in suburbia to collective functional programs in the post war garden city.

The study and visualization have been presented at the very well visited Rotterdam Rooftop days and will be used to further develop a new city policy for sustainable roofs in 2015-2016.