Are Green Roofs a Benefit for Stormwater Management?

This is a great question—one that we’ll be exploring in depth throughout 2025. Each month, we’ll highlight projects across North America, showcasing how LiveRoof® green roofs contribute to effective stormwater management.

Research has shown that extensive green roof systems can reduce stormwater runoff by up to 60-100% annually (impacted most significantly by climate, soil and pitch of roof). Living roofs act as a sponge to absorb much of this runoff and keep waterways cleaner.

To kick things off, let’s examine some of the keyways LiveRoof® green roofs positively impact stormwater management.

Green Space Compliance = Monetary and Other Rewards

Green roofs typically qualify for credits associated with green/open space and onsite stormwater management in many municipal zoning ordinances; often equating to time and money savings in the zoning process or financial rewards from tax credits and other incentives and avoidance of stormwater discharge fees.

Pollution Prevention

Reducing stormwater also reduces pollution; Rainwater carries airborne pollutants (from combustion engines, dust and VOC’s) and when it rains this pollution ends up hitting hard surfaces and running into storm sewers and watercourses. Rainwater that hits green roofs, however, is captured to a large degree and filtered by the soil, and whatever is not captured, comes out with fewer pollutants. The green roof is essentially a living filter.

Financial Benefits for Municipalities

The general public may not be conscious of this, but the cost of sewage treatment is a tremendous monetary burden for municipalities with combined storm and sanitary water systems. By sponging up water on the roof, via green roofs, municipalities are able to reduce the need for constant and costly expansion of storm water treatment facilities.

‘Sponge City’

Last fall, ReNew Canada published an insightful article celebrating the 15th anniversary of Toronto’s Green Roof Bylaw. Titled “A ‘Sponge City’ Approach to Flooding and Climate Resiliency,” the article explores how the bylaw has significantly improved the city’s stormwater management.

To read the full article, click here.

About

LiveRoof Global, LLC, subsidiary of Hortech, Inc., is the premier provider of modular green roof systems. With a focus on environmental stewardship and design excellence, LiveRoof transforms rooftops into vibrant, sustainable spaces that benefit people, buildings, and the planet.

About this Article:

This is the first article in the series: Green Roofs for Stormwater Management. Throughout 2025 network grower specific articles will be distributed monthly. We hope you enjoy the series. I’m Jodi Griffin, Business Development Manager for LiveRoof® Global and can be reached via email at jodi@liveroof.com.

For more information about LiveRoof® Global, LLC - Click HERE