We like MVRDV’s catalogue of new ideas for rooftops

Whether it's green roofs, solar installations or sky-high farms, rooftops are slowly becoming more than just a way to protect a building from the elements.

To speed up the process and broaden the scope of potential functions, the city of Rotterdam commissioned architecture and urban design firm MVRDV to write a catalogue of ideas for rooftops. Rotterdam has 18.5 km2 of – mostly empty – flat roofs.

MVRDV came up with 130 ways to repurpose rooftops, from tiny houses and urban campsites, to classrooms and athletic fields, to hubs for delivery drones and parking and landing space for air taxis. They're not all utilitarian, either: there's a green maze, a tropical palm conservatory, and — one of our favorites — the super hammock, which would be a gigantic net suspended between rooftops, creating an aerial playground for adults and children.

Another area of interest is densification — adding new buildings on top of buildings. In a neighborhood with few families, for example, larger, child-friendly apartments could be added to rooftops to create a more diverse neighborhood.

Meant to be a practical guide, the catalogue includes which types of roofs an idea can be used on, which UN Sustainable Development Goals are applicable, and which urban challenges it addresses. The ideas are also color-coded based on the functions they add: a yellow rooftop, for example, provides renewable energy, while a red rooftop offers social opportunities.