Green roofs and green walls, used to address environmental issues like air pollution, heat-island effect, and loss of green spaces in cities, will balloon into a $7.7 billion market in 2017, driven by mandates and incentives by cities across the globe, according to Boston-based Lux Research.Green roofs will account for $7 billion of the market, presenting a $2 billion opportunity to suppliers of polymeric materials such as geosynthetic fabrics and waterproof membranes. Green walls will swell to a $680 million market, using $200 million worth of materials such as self-supporting polyurethane foam growth media, the study found.

“The environmental benefits of building-integrated vegetation (BIV) remain hard to monetize, and many wonder if it’s just a green curiosity,” said Aditya Ranade, Lux Research senior analyst and the lead author of the report. “But with key cities around the world putting incentives in place, a significant market opportunity is emerging.”

In response to environmental issues caused by rapid urbanization, cities such as Copenhagen, London, Singapore, and Chicago have announced mandates or incentives for vegetated roofs to reduce stormwater volume, clean air pollutants, reduce the urban heat-island effect, and sequester carbon dioxide, the report notes. There also have been a number of demonstration projects for vegetated walls that offer similar benefits. However, the study goes on to say, the environmental benefits remain hard to monetize, and questions persist on whether urban vegetation will become a mainstream market.