Sourced from Philadelphia Magazine
Charlie Miller, engineer and founder of Mount Airy-based Roofmeadow, has become Philly’s go-to green roof guy. Here, he breaks down why they’re the hottest new accessory for downtown buildings.
First and foremost, green roofs manage storm water.
“Green roofs are very thin and cover broad areas, changing the response of surface to runoff in a way that’s more like normal runoff conditions,” says Miller. When you green the roof with a layer of plants and the dirt they root in, rainfall is absorbed and kicked back into the atmosphere (via a process called evapotranspiration), not just drained into city sewers.
And managing storm water is better for the city … and bottom lines.
Like many cities, Philly has a combined sewer system, so runoff and toilet water flow into the same treatment plant. Heavy rainfall can overwhelm this system, and that, Miller explains, leads to “all that gunk getting dumped directly into the Delaware, the Schuylkill, or the nearest overflow point.” This damages ecology and, well, it’s gross. That’s why the city provides incentives for installing green roofs.