🌿 Green Roofs Trap 97% of Microplastics — A New Role for Nature-Based Solutions

A new study has revealed an exciting and timely benefit of green roofs: they can capture up to 97.5% of airborne microplastics during rainfall. Conducted by Tongji University and published in Communications Earth & Environment, the research investigated how different rooftop configurations impact microplastic filtration.

The findings are clear. When simulated rainfall passed through bare roofs, soil-only layers, and green roofs planted with Sedum lineare and Rhodiola rosea, the soil-based green roof systems intercepted the vast majority of microplastic particles. Even under light rainfall conditions, almost all fragments were prevented from reaching the drainage system. Notably, it was the soil layer—rather than the plants themselves—that performed the bulk of this filtration.

🌍 Why It Matters: Tackling an Invisible Pollutant

Microplastics are a growing environmental and health concern. These tiny plastic fragments (less than 5mm in size) have been detected in rainwater, rivers, food, and even human lungs. With their long-term effects still largely unknown, reducing their presence in the environment is critical.

Green roofs are already known for their ability to reduce stormwater runoff, support biodiversity, and improve urban temperatures—but this study adds a compelling new benefit. By acting as a microplastic filtration system, green roofs help cities combat pollution at the source, before particles can enter waterways or the wider ecosystem.

In Shanghai, where green roofs cover around 3.5 million m², researchers estimate that more than 56 tonnes of microplastics could be intercepted annually. This is a powerful case for accelerating green roof adoption in urban environments around the world—including across the UK.

🌱 SkyGarden: Delivering Nature-Based Solutions

At SkyGarden, we provide nature-based solutions that contribute to healthier, cleaner cities. Our green roofs aren’t just decorative—they’re functional, multi-benefit systems designed to integrate with modern construction and urban design.

Our systems combine high-quality substrates, expertly selected plant species, and intelligent irrigation systems. These components not only support robust plant growth but also create the ideal conditions for environmental filtration—exactly as outlined in the recent research.

As green infrastructure specialists, we work with developers, architects, and local authorities to design solutions tailored to each project. Whether it’s an intensive green roof on a commercial building or a lightweight extensive system for a domestic development, SkyGarden is uniquely positioned to deliver solutions that meet both performance and sustainability goals.

🏙️ Building Resilient, Cleaner Cities

The message is clear: green roofs are no longer just about aesthetics or biodiversity—they are powerful tools for climate resilience and pollution reduction. With their proven ability to filter out microplastics, they represent a vital nature-based solution for modern urban challenges.

If you’re planning a project and want to make a measurable environmental impact, talk to SkyGarden. Together, we can create buildings that don’t just look green—but act green too.

Contact us today to explore how our green roof systems can support your sustainability targets and help future-proof your development.