7 Ways Cities Are Transforming Urban Rooftops

With street-level space at a premium, urban rooftops are underused spaces ripe with potential

BY MEGAN BARBER@MEGCBARBER  SEP 5, 2017, 4:00PM EDT

As a sweeping construction boom renders U.S. cities ever denser, there’s one type of urban space that’s still an untapped resource: rooftops.

Sure, every city lover can name a handful of rooftop patios with great views or a favorite rooftop hotel pool. But for the most part, roofs remain in the domain of the squarely utilitarian, home to chimneys, air ducts, and satellite dishes. That can change.

According to Steven Peck of the Toronto-based non-profit Green Roofs for Healthy Cities, “The roofscapes of our cities are the last urban frontier—from 15 percent to 35 percent of the total land area.” And they can offer much more than just a pretty view. For example, rooftops can provide room to grow food, build affordable housing, and green our cities, to name a few.

Below, check out seven ways urbanites are transforming roofs from empty dead spots into spaces for innovation.

Green roofs

A common way to transform an unsightly rooftop is to add greenery. But vegetation can do far more than create an urban oasis. Green roofs covered in plants can reduce stormwater run-off, lower cooling costs, and combat the urban heat island effect.

One compelling example comes from Vietnamese architect Hung Nguyen, who designed a roof pavilioncovered in plants with air-purifying properties. Other homeowners use drought tolerant, low-maintenanceboth plants like sedum to create a green roof that can withstand even harsh winter climates.

Rooftop farms

Larger rooftop gardens can also become farms. In New York City, Brooklyn Grange runs rooftop farms in Long Island City, Queens and The Navy Yard in Brooklyn, producing tens of thousands of vegetables a year that are sold directly to urban restaurants and greengrocers. Chicago boasts the world’s largest rooftop greenhouse, a 75,000-square-foot facility set atop an old factory. Operated by Gotham Greens, the farm uses a state-of-the-art hydroponic system with a yield that rivals that of a 50-acre farm.

Beyond transforming unused space into eco-friendly agriculture, rooftop farms also reduce transport costs by growing products in close proximity to metropolitan areas. These farm create a more bio-diverse ecosystem in cities, as well, attracting birds, insects, and butterflies.

Gwen Schantz, founding partner and COO of Brooklyn Grange, told Curbed, "I feel like what we’re doing is part of the food movement," she observes. "But it’s also part of the movement to bring green space back into the city and to improve the health of the plants and the animals, but mostly the health of the people here." Head over here for more on rooftop farming.

Affordable housing

In dense cities with high-priced real estate, rooftops could be the final frontier of affordable housing. Berlin-based architects Simon Becker and Andreas Rauch launched Cabin Spacey to help solve the urban space crunch by building tiny homes on some of Berlin’s 55,000 unused roofs. Becker and Rauch’s cabins—still in the concept stage—can house up to two people in 250 square feet, and can run fully off the grid thanks to solar panels attached to the roofs.

In London, PUP Architects created a tiny dwelling that looks like an air duct as a playful nod to the planning rules that allow rooftop mechanical equipment to be installed without permission. Called H-VAC, the design was the winning entry in the inaugural Antepavilion competition, which explores innovative and alternative ways of living in the city—especially on rooftops.

Recreation areas

Another way cities are trying to take advantage of wasted roof space is to use them as recreational areas. Rooftop pools have long been a staple of high-end hotels and condos, but larger gyms, soccer stadiums, playgrounds, jogging paths, and even open-air cinemas are becoming more common. In Miami, a new apartment complex has rooftop tennis courts and a track, while the 30-acre Paramount Miami Worldcenter—set to be completed in 2019—will have a soccer field over an office building.

In Tokyo, Japan, people can play soccer on the roof of the Shibuya Hikarie skyscraper, while in Osaka, a 1000-foot astroturf track stretches across multiple roofs at Morinomiya Q’s Mall Base shopping complex.

Chicken coops and apiaries

A natural progression from gardens and farms, chicken coops and beehives are another innovative addition to city rooftops. Chickens can be raised in relatively small spaces—each hen only needs about four square feet—and can provide a whole apartment building with fresh eggs. Rooftop chicken coops have already made it onto some Seattle apartment buildings and New York City hotels.

Likewise, beehives on hotels and skyscrapers can provide businesses with honey for cocktails, food, and spa treatments.

Rainwater collection systems

As the first point of contact—known as the catchment area—for rainfall, roofs can be an optimal way to harvest rainwater. This age-old method of collecting water may not be as common in the United States as it is in developing countries, but it’s becoming more popular. Especially in drought-afflicted states, harvesting rainwater can be an excellent way to retain stormwater runoff, reduce pollution, and reuse hundreds of millions of gallons of rainfall every year. While not fit for drinking water, harvested rainwater can be used for non-potable purposes like yard watering and toilet flushing.

Philadelphia, Pennsylvania, has incentivized rain collection by imposing “stormwater charge” on properties based on the size of impervious space on the property; homeowners can lower their stormwater charge by adding more green space.

Solar power

The most obvious and common use of rooftops is still for solar power. It makes sense: Unlike many city streets, rooftops have unobstructed access to sunlight and enough space to make larger-scale solar panel installations feasible. And while the idea of solar panels on roofs may not seem innovative, the industry is going through big changes.

For one, new rooftop solar tiles from Tesla look nothing like the solar panels of yore. The Tuscan glass tile tiles and textured glass tiles look just like conventional roof tiling, which could mark a new age of rooftop aesthetics. Other startups are chasing similar concepts.

Elsewhere, the solar industry is trying to make rooftop energy a community endeavor. Around 10,000 Australian homeowners are participating in a pilot program testing the world’s first open market for monetizing rooftop renewable energy and storage. And in Brooklyn, a new energy startup links up neighbors who have solar panels with those who want to buy clean energy, creating the Brooklyn Microgrid.