Green roofs are flat or gently pitched roofs overlaid with a growing medium and plants, creating a habitat on what would otherwise be a plain surface.They are sometimes called living roofs or vegetated roof structures.

Green roofs are one of the most tangible elements of a sustainability strategy, being visible, natural and distinctive. On many projects, green roofs can be used as a symbol of “greenness” and, as a result, their contribution to sustainability and biodiversity can be overlooked.

In addition to providing an attractive, roof-level habitat, living roofs can also contribute to the management of surface water run-off, the mitigation of local air pollutants and the extension of the useful life of the roof membrane.These benefits are secured in part by the building owner and, if there is enough green roof to make a difference, by the wider community.