Green Roofs

Did you know: You can use a vegetative covering on your roofs?

Yes, it is called a green roof system.

What is a green roof?

A green roof is a vegetation layer planted on an insulating system on a flat or slightly pitched roof. Vegetative or eco–roofs are other names for green roofs.

Green roofs serve a variety of functions for a building, including absorbing rainwater, providing insulation, creating natural habitats, increasing benevolence and reducing stress among those who live near the roof by providing a more aesthetically pleasing landscape, and lowering urban air temperatures and mitigating the heat island effect. Green roofs can be installed at small garages or larger industrial, commercial and municipal buildings for renovation or redevelopment projects as well as new construction. In urban and suburban landscapes they effectively use the natural functions of plants in water and air treatment.

Types

Depending on the depth of the planting medium and the amount of maintenance required, green roofs are classified as extensive, intensive, or semi–intensive.

Extensive Green Roof

An extensive green roof has a shallow growing medium (usually less than six inches), a low roof load, limited plant diversity, low watering needs, and is frequently inaccessible.

Intensive Green Roof

Intensive green roofs include more soil and a deeper growing medium (up to several feet) to support a wider variety of plants, including small trees. As a result, they bear more structural loads and require more frequent care and watering. They're typically reachable.

Semi-Intensive Green Roof

Both forms of green roofs can be found on semi–intensive green roofs. The depth of any green roof is determined by the construction of the roof, the plants chosen, annual rainfall, and stormwater performance requirements.

to be continued...

Photo Credits:

1. Green roof at the British Horse Society headquarters (https://en.wikipedia.org/wiki/British_Horse_Society)

2. Typical Green Roof section (TURAS green roof design guidelines)

3. Green Roof types (By Genetics4good - Own work, CC BY-SA 4.0)