Green roofs take space that's most often completely wasted and transform it into energy-conserving gardens. Sometimes, architects even take the opportunity to create lush new green spaces that serve as parks, vegetable gardens and can even be accessed directly from ground level.
Nanyang School of Art, Singapore
The Nanyang School of Art in Singapore boasts one of the most beautiful and unusual green roofs in the world, with a swirling design that extends from ground level to the roof of the fifth story. This allows students, faculty and visitors to walk the entire length of the roof without ever climbing stairs or taking an elevator.
Vo Trong Nghia Farming Kindergarden
The concept of a 'farming kindergarten' is pretty incredible in the first place, where preschoolers get to learn about the importance of caring for the environment. But this school by Vo Trong Nghia Architects in Dongnai, Vietnam takes it one step further with a beautiful green roof that serves as the setting for educational gardens.
Wavy Hill-Like Apartments in Gothenburg, Sweden
This concept could not only make use of an under-utilized block in the city of Gothenburg, it would provide recreational space and more air-filtering greenery for the entire community. New Heden is a concept for buildings "built as sliced hills with grass roofs that can be walked upon" so they become terrain.
Marina Barrage, Singapore
The massive landscaped roof of the Marina Barrage dam at the mouth of the Marina Channel in Singapore is a public recreational park the size of four football fields, with amazing views of the scenery.
Villa Bio, Spain
The suburban house of the future has just as much green space without taking up such a large footprint, as envisioned by Cloud9 Architects. Volcanic stones on the roof provide the basis for a hydroponic rooftop garden that travels across the split-levels of the home.
OUTrial House, Poland
Another home almost seems to blend into the landscape altogether. KWK PROMES architects created this residence in Poland that seems to be carved out of the hills themselves. The ground floor is linked to the grassy roof through an 'incision' in the green plane inside the building.
Green-Roofed Staircase Office
This concept by NL Architects features a stepped design that offers tier after tier of landscaped roof, so every level of the building has green space and unobstructed views.
University Library, Warsaw, Poland
Often referred to as the world's greatest green roof, the park on top of the University of Warsaw's library has grassy ramps that lead from one level to the next. It's easy to forget you're actually walking on a rooftop and not the ground – until you pass a skylight nestled among the plants.
Jubilee Park Canary Wharf, London
In the midst of one of the world's most metropolitan cities, surrounded by a landscape of steel and glass, Jubilee Park offers a green zone in the form of a rooftop garden on top of the Canary Wharf Underground Station.
Beaux Arts Green Roof, Quebec
Not only does this sloping green roof extend from ground level straight up to the sharp end of a rooftop gable, it's also unusual for its highly geometric form. The proposed expansion of the Beaux Arts building in Quebec would reduce water runoff, cut energy usage and offer additional recreational space for visitors.
Buk Seoul Museum
Meander across the multi-level rooftop of the Buk Seoul Museum expansion by SAMOO Architects and Engineers, designed to create a lush oasis in the midst of the city's high-rises.
Villa Topoject, South Korea
This striking home in a mountainous area near Seoul, South Korea was designed to mimic its natural surroundings with grassy sloping peaks that offer green space on every level. Lots of floor-to-ceiling windows overlooking these spaces blur the boundaries between indoors and out.
Marcel Sembat High School
Rehabilitating the existing Marcel Sembat High School, archi5 Architects added a series of green roofs that reach out to connect to a public park located to the south side of the site. The slices between the 'blades' of the roofs contain skylights to bring more daylight indoors.