In the 19th century when large residential complexes were built, the servant quarters were often put in the attic or added on the roof. In European cities like Paris and Barcelona and some American cities like New York these spaces have become highly desirable and expensive penthouses with roof terraces or even trendy rooftop bars, restaurants, clubs or public roof gardens. This seems to happen only in places where the price of land is so high that every square metre counts and where the location and design solution are so sought-after that it is worth expanding into the loft or on the roof. While it may be a question of luxury in these cities, in other places it’s a question of necessity.
Around the world, inhabited attics and rooftops are a common feature in many big cities with high urban density. Flat roofs are often easily accessible, whether in a single family home or a block of apartments (where the wash can be hung out to dry). Small-scale living or bedroom additions (beds for servants, family or visitors) in the ‘better’ neighbourhoods are often condoned. In the cheaper neighbourhoods, rooftops are rented out to build shack-style penthouses or have been taken over by illegal slumming. Not necessarily problematic, as proudly listed Airbnb locations attest. It’s all about supply and demand.
This is precisely the challenge that the Dakdorpencollectief (Rooftop Collective) faces: understanding the supply and demand for useable space. Rotterdam launched a Green Roofs plan in 2016 to create a buffer for the city to absorb excess water in a sea of concrete and paving. The municipality coupled this with subsidies (initially 25 euro cents per square metre and since 2019, 15 cents/m2) and now stipulates green roofs as a priority in new build projects. Converting an existing roof into a green one costs around 65 euros/m2, so it has to be a serious undertaking if such an investment is to be added to any works.
In the meantime, roof spaces have become popular as alternative spots for the public, in emulation of the successful conversions/extensions found in the prosperous cities with real urban density. Water buffers, stemming initially from need, can be turned into a ‘fun feature’. Yet, green roofs are still a policy need more than a market demand. That is not to say that they can’t become market driven – provided that laws and regulations can be developed, the social consequences of temporary or permanent habitation of rooftops can be understood, and the right business model can be found. These are necessary to implement ideas that are attractive though perhaps not yet market-ready.
It’s fantastic that the Rooftop Collective is going to research these very questions and FGF is gladly contributing to the cause. If the conclusions of the study reveal that a feasible business model is unrealistic, as unlikely as this may seem, then the Municipality of Rotterdam and the water authorities know what they need to do: subsidize policies because they are necessary policies, but also because greenery adds beauty and beauty is worth the effort, particularly when it adds happiness to the lives of Rotterdammers.
Prof. Dikkie Scipio
1st quarter 2019