Comprising up to 26 percent of urban areas, rooftops are a prominent, but often underused element of modern architecture. According to Michigan State University's green roof research team, greenery can enhance the durability of these structures, reduce the quantity of stormwater runoff, and act as a natural filtration system to cleanse runoff before it reaches waterways like our very own Red Cedar River.

Initiated in collaboration with Ford Motor Company in 2000, MSU's green roof team was assembled to advise the automobile giant on incorporating green roofs into construction of a new assembly plant at the Rouge Complex in Dearborn, Michigan. "They had a lot of concerns about stormwater runoff carrying pollutants into the river," said lead green roof researcher and professor in MSU's Department of Horticulture, Brad Rowe, "but instead of abandoning the site, they used green roofs, porous pavement and retention ponds to help reduce runoff and naturally clean the area."

Continued funding from this partnership allows the team to investigate various installations, applications and uses for green roofs, using campus as a laboratory for research by top faculty members and students. Areas of research vary widely, from carbon sequestration and microclimate moderation to pollution, public awareness and wildlife habitat relationships. Rowe and his team currently manage eight green roofs on campus in addition to numerous smaller research plots.

"The campus green roofs are a great research tool," said Rowe, "they allow us to track things like roof temperature and growth of different plants. On the Plant and Soil Sciences Building green roof alone, we've been monitoring the long-term growth of 16 different plant species for 13 years."

In addition, Rowe regularly works with graduate and undergraduate students on smaller research projects that address industry challenges. Currently, the team is investigating a unique solution to "growing media," an engineered soil used on green roofs that mimics the properties of natural soil, but weighs less and helps better manage moisture within a roof drainage system. Traditionally, the material is made of heat-expanded slate or shale, which works well but requires a lot of energy to produce.

Rowe's idea: crush waste porcelain into small pieces and use it as one of the components for the engineered soil, removing some of the energy demand. "It wasn't as good as traditional product, but the results were promising," said Rowe, "I think we can make some educated adjustments and see more success, starting by crushing the material into finer particle sizes. We're definitely moving in the right direction."

A photo of succulents growing from engineered soil that contains a recycled porcelain coffee mug handle.
One of Rowe's green roof research plots growing succulents from engineered soil that contains recycled waste porcelain.