A semi extensive Green Roof can be described as a roof planted with a mix of succulents like Sedum, together with grasses and small shrubs

A Semi Extensive Green Roof is a system characterized by small herbaceous plants, ground covers, grasses and small shrubs. They require moderate maintenance and occasional irrigation. A typical growing medium depth for semi-extensive green roofs would be around 6 to 12 inches. These systems are able to retain more storm water than an extensive system and host a richer ecology. Though higher in maintenance, this green roof system also provides the potential for a formal garden effect.