Studio Gang

Context 

When Chicago-based architecture and urban design practice Studio Gang decided to relocate to its new office in 2015, the firm realized it would be losing a critical piece of infrastructure: a well-used outdoor green space for employees to relax and enjoy social events. The new building in the predominantly residential area of Pulaski Park had no such feature. Creating a sweeping green roof that provides social and community as well as ecological benefits was Studio Gang’s solution.  

To transform the 4,700-square-foot roof into a green roof, Studio Gang partnered with Omni Ecosystems, a Chicago-based firm specializing in living infrastructure. The rooftop supports biodiversity, resilience, and community access that facilitates education, as well as socialization, community events, and client engagements. Studio Gang emphasizes the importance of using this roof as a laboratory to explore how a relatively small space can contribute to an area’s biodiversity, ecological health, and climate resilience. In addition to the thriving biodiverse ecosystem that has been established on the roof, the robust community of citizen-scientists, ecologists, students, and staff that use the space on a regular basis is a testament to its success.  

To achieve Studio Gang’s goal of creating a green roof that could serve as a living laboratory, Omni Ecosystems provided its meadow system; which contains a six- to eight-inch medium of biological matter that supports more than 70 species of plants. As Jesse Rosenbluth of Omni Ecosystems said, “The microbial and the fungal communities [in the medium] allow the plants to thrive and succeed long term. Resilience is not only about being able to weather different climatic impacts and events, but also about surviving not for one year or two, but for 20, 30, 40, 50 years.” These systems are also cost-effective in their planting methodology, using a seeded system rather than an extensive assembly of existing plants. The biodiversity of the Studio Gang rooftop is crucial for its success, because the roof is an ecosystem that plants adapt to over time. 

Resilience Strategies 

Biodiversity

This rooftop extended the typical climate benefits of green roofs by including various biophilia and food-producing crops. Having this biodiversity allowed the environment to self-correct year over year, minimizing the need to maintain the ecosystem manually. As Rosenbluth put it, “The biodiversity allows [the system] to respond to all different types of climate pressures, so if a couple [of] species die, others are there to take off. It adapts to different microclimates of the roof, and really can do what it does because of its diversity. The advantage of a meadow system specifically, is you’re getting this extensive green roof that is going to change over time and grow into the best version of itself.”  

Studio Gang manages the space, which functions as a living research laboratory to answer the question, “How much can even a small area of 5,000 square feet contribute to biodiversity within this neighborhood?,” as Juliane Wolf, design principal at Studio Gang put it. In 2021, experts, community members, and students participated in Studio Gang’s trademark BioBlitz event, identifying 160 unique organisms spanning vegetation, fungi/lichens, insects, birds, and mammals. To foster this biodiversity, Studio Gang advised Omni Ecosystems on species selection for plants, considering wildlife in the area. The firm consulted an avian expert to assist with the installation of bird-safe frit glass, which also has the benefit of increasing energy efficiency by decreasing solar heat gain. Studio Gang planted three species of milkweed to attract the monarch butterfly, a species that has become endangered through rampant habitat loss.  

When creating seed lists for the rooftop, Studio Gang was careful to select species that worked well together and were native to the Illinois prairie. They included wildflowers, grasses, vines, and trees. When the project was opening, it was late in the season, so wheat was planted as a one-off cover crop. Although often overlooked, the species is very resilient, and its qualities ensured the nascent prairie survived the winter. As noted by Lydia Link, urban ecology specialist with Studio Gang, advised on species selection, “We’re always trying to maximize biodiversity, and when you do that, you create very resilient systems and systems that are extremely supportive of the native landscape. Many prairie plant species are perennial, long-lived, long-rooted plants that are very resilient to heat, cold, and wind, which rooftops are excessively exposed to.”   

Urban Agriculture

The wheat cover crop provided an early opportunity for community engagement. High school students involved in an after-school program called After School Matters partnered with Omni Ecosystems, The Roof Crop, and Urban Habitat Chicago to hand harvest the wheat crop. The students then winnowed and threshed the wheat, deploying creative solutions for separating the wheat from the chaff. Baker Miller milled the wheat into 66 pounds of high-grade pastry flour, which was used to bake cookies that the students sold as part of a fundraiser. Beyond the impact this experience had for students, it also showcased that these green roofs can support the growth of staple crops like wheat, not just fruits, vegetables, and herbs. Wheat is a high-calorie, dense food. While it is readily available in rural areas, urban environments must import the wheat they use. When recognizing this rooftop, ASLA Illinois noted that in the United States wheat consumption exceeds consumption of any other food staple, so it is eminently suitable to include wheat in conversations about urban agriculture. As global population grows, the need for local food sources to mitigate food scarcity and insecurity will only increase, especially in densely populated areas.  

Urban Heat Island Reduction and Air Quality

When traditional rooftops absorb the sun’s radiation it dissipates into the surrounding air, which increases the urban heat island effect. In contrast, green roofs reflect this radiation; thereby creating a cooling effect on the surrounding air. The trees and other vegetation included on Studio Gang’s rooftop further cool temperatures through shade. ULI’s Scorched details that by reducing extreme temperature fluctuations, green roofs not only create a comfortable environment for occupants but also extend the life of a roof.   

These cooling effects also affect air quality. As explained in the U.S. Environmental Protection Agency (EPA)’s case study Estimating the Environmental Effects of Green Roofs, air pollutants contribute to warming by trapping excessive heat and negatively impact lung health in humans. The cooling effects provided by green roofs lead to less ozone production, while plants absorb existing ozone. In addition, moderating building temperature helps regulate the heating and cooling needs of the building, mitigating pollution from electricity generation and the resulting negative effects on air quality. Studio Gang installed an air quality monitor on the rooftop and another at the building’s ground level. The data collected between May and July 2021 shows the air quality on the rooftop to be significantly better than that shown by the sensor at street level.  

Stormwater Management

Omni Infinity, which is an advanced replication of soil, has been used for stormwater management on both the structure of Studio Gang’s vegetative roof and on-grade applications, enabling the rooftop and the overall site to meet their stormwater objectives. Stormwater provides most of the hydration needs for the rooftop, with only some supplemental irrigation needed in summer months. In this way, the roof helps with stormwater management by absorbing excess stormwater for use as irrigation. This further benefits the sewer system by reducing the volume of water and minimizing the environmentally harmful effects of combined sewer overflows. Chicago has a combined sewer system, which is susceptible to combined sewer overflows during large rain events. Stormwater management in the city is vital to combating the effects of future larger, stronger storms on the city’s infrastructure and residents. ULI’s Harvesting the Value of Water elaborates on the benefits: “Green roofs work to capture, retain and slow the release of stormwater during routine and peak events. In the aggregate, many distributed green infrastructure elements can reduce the need for buried storm sewer systems and end-of-pipe detention systems, thus lowering infrastructure costs and providing more developable land.”  

Value Proposition  

• Added Amenity and Talent Attraction/Retention: The social, community, and resilience benefits provided by this green rooftop are a clear value add for Studio Gang and for the property. Outside of larger community events, the employees of Studio Gang can use this space daily to decompress. Green spaces such as green roofs provide financial benefits in addition to community benefits. In another project with substantial green roof area, District House saw material increases in value for units that had access to lawned terraces and green roof areas.  

• Energy Savings: Green roofs reduce electricity costs. The growing medium insulates while the larger vegetation shades the building, resulting in lower heating and cooling costs. The less electricity needed by buildings, the less strain is put on the regional grid. According to the EPA, “Green roofs can reduce building energy use by 0.7% compared to conventional roofs, reducing peak electricity demand and leading to an annual savings of $0.23 per square foot of the roof’s surface.” Beyond the aesthetic and social benefits, as city policies around sustainability and resilience evolve, green roofs are likely to become encouraged if not required in many dense cities. These energy savings can be further enhanced when paired with renewable energy sources. Studio Gang now has photovoltaic panels on its green roof that provide 3 percent of the building’s energy use, which is equivalent to the energy needed to power all of the firm’s laptops. 

• Reduced Operating Costs: In Project Drawdown’s Table of Solutions, which looks at how effective various mechanisms are at carbon reduction, it notes, “If cool roofs grow from 5 percent of its relevant roof market at an annual 8–10 percent rate (CAGR) to 2050 and green roofs similarly grow from 1 percent at 9–11 percent annually. . . . [C]ombined, these technologies could reduce carbon dioxide emissions by 0.6–1.1 gigatons at a cost of US$624 billion to $954 billion, with lifetime operating savings on heating, cooling, and maintenance of US$330 billion to $593 billion.” 

• Awards and Recognition: Given its many co-benefits, Studio Gang’s rooftop has won multiple awards. In 2017, it won an Award for Excellence from Green Roofs for Healthy Cities for the extensive industrial/commercial category. It also won a Merit Award for Architectural Research from the Illinois chapter of the American Society of Landscape Architects.  

Lessons Learned 

This rooftop publicly presents the values Studio Gang upholds. Its space has inspired clients’ interest in green roofs and the ability to mitigate climate risk while creating a cross-functional space that can be enjoyed by team members, collaborators, and the community. As a living system, this rooftop is constantly evolving and teaching the team new things, and in many ways the project is never finished. Rosenbluth noted that upfront, in-depth cost analysis is key to demonstrate the life cycle costs—and benefits—of the system. Often, factoring in long-term cost savings can make a clear financial case for including such systems in a project.   

Rosenbluth summarized his learnings as follows: “We have this unique opportunity when working in the built environment, whether you’re a developer or a contractor, or a landscape architect, or designer, to have this long-term impact for the better. Buildings are key to driving economic change, social change, all types of innovation within cities, and if you go that extra mile, you can provide long term value. The stormwater, urban heat island, air pollution, and biophilic benefits all accrue over time, so having a 20-, 30-, or 40-year lens when building these systems is vital.” For Juliane Wolf, design principal of Studio Gang, this rooftop showed, “No matter how small your property is, there is a lot of positive impact you can have.”   

ULI is grateful for the support of The JPB Foundation.