As an initiative to make better use of space, Chicago started focusing on transforming the roofs of buildings to be more green. A green roof simply means that there is vegetation growing on top of a building, whether its a skyscraper or a garage. There are many benefits to green roofs, such as water cleaning and retention, reducing air pollution, adding beauty to a space normally overlooked, and reducing urban heat island effect. The combination of parking lots, asphalt roads, and dark rooftops all densely packed into a city cause its temperatures to be higher than surrounding rural areas. The city of Chicago wanted to research ways to battle this effect, and one of the most notable ways it did was with the building of the green roof on top of City Hall. The 20,300 square foot garden on the roof has over 150 varieties of plants to research the benefits of these gardens and how they can cool the air, store rainwater, and their survivability in the city.
Chicago is extending policies to encourage everyone to get involved in green roofs too. Buildings with green roofs are eligible for Floor Area Bonuses (under 17-4-1015) if the green space covers at least 50% of the net roof area or 2,000 square feet of contiguous roof area. They even have a bonus formula: (area of roof landscaping in excess of 50% of net roof area ÷ lot area ) × 0.30 × Base FAR, which incentivizes building more vegetation on roofs.
With other environmental building incentives like LEED standards and even the Living Building Challenge becoming more popular, green roofs is just a small first step that can get people invested in sustainability. All it takes is for the government to create these policies and incentives to get people to invest in it, and like Sturgeon says in “Beyond net-zero: The rise of the Living Building Challenge,” the appeal is “the connection between a Living Building and the change they want to see in the world.”