Soil and Styrofoam: How Leaf Island recycles styrofoam into soil for green roofs

“I grew up in an inner city immigrant neighborhood in Brooklyn and finding nature in New York City was challenging,” shared Igor Bronz, the Head of Design at Leaf Island. “In my mind, there was no way to integrate nature into the [urban] environment at the time.”

Now, Bronz sees the city a bit differently. He is working at Leaf Island, a company that designs green infrastructure products and technologies, to make green roofs more affordable and accessible to the people in New York City. The company is looking to set up facilities near New York City, where there is demand for green roofs. Bronz shared that Leaf Island is focused on the “entire solution” when it comes to environmentalism, which is why a goal of his is that one day, anyone will be able to have a green roof.

“The whole point of green roofs is that we’re taking all this rainwater that comes down and we’re storing it on the rooftop, so we’re preventing it from going into the sewage system, which prevents the possibility of sewage overflows,” said Bronz. “We’re also turning this water into energy. We’re essentially using plants as the vehicle to take this water up into the root system and then it transpires, which produces cool air. This energy is directed towards cooling the atmosphere.”

Leaf Island accomplishes this and even improves the process with the help of GaiaSoil, a green roof medium that is ultra-lightweight and made with recycled styrofoam. The styrofoam replaces the “bulk” of the soil, the sand, gravel, and silt, which do not serve an ecological purpose the way the clay in the soil does. Because it is mostly styrofoam, GaiaSoil is porous and lightweight, allowing the useful parts of soil, such as clay, fungal networks, and organic matter, to be used more effectively, accelerating plant growth by about 40-60 percent. It is also easier to transport and use for green roofs over regular soil because of its weight.

Another benefit to GaiaSoil is that it prevents styrofoam from ending up in landfills. About 99 percent of styrofoam is not recycled. In the GaiaSoil, the styrofoam is much less likely to turn to microplastics because the plants will prevent it from being heavily eroded and exposed to UV rays. Furthermore, on green roofs, the styrofoam will not be mixed with substances found in landfills that could release microplastics when the materials are combined. Essentially, when the styrofoam is used in GaiaSoil rather than ending up in a landfill, it is less likely for it to become harmful and seep into waterways.

Leaf Island is also working with aluminum because it can be recycled endlessly, unlike plastic. They are currently testing modular trays made with aluminum.

“We’re not really trying to maximize profits or returns,” said Bronz in reference to the aluminum trays. “We’re trying to create products that are as good for the environment as possible.” Leaf Island is currently trying to expand and build more facilities. Bronz shared that shipping costs and the environmental impact of shipping GaiaSoil long distances can be counterproductive, which is why having more locations set up will be beneficial to
the company and to its mission.

“I think that every environmental issue we’re facing today is possible to solve through reintegrating ecology back into our cities and realigning the metabolism of cities into something that’s circular rather than linear,” said Bronz. “I’m very optimistic about these environmental issues and our ability to solve them.”