Extensive Green Roof Thickness

Vegetative roofs are divided into two categories.

Extensive green roof thickness.

Extensive green roofs are simpler lighter weight systems commonly seen on residential buildings. It is common practice to use the term extensive to describe green roofs that are very thin and will only support hardy drought resistant vegetation such as sedums herbs and perennials. The substrate is usually an aggregate mixed with about 20 organic material. The planting medium in extensive green roofs ranges from 1 6 to 6 inches deep and while deeper systems have been installed they are not favored as much as the shallower systems drought tolerant sedums succulent plants and grasses are the typical plants used since they are shallow rooted and use little water plant diversity on these roofs is kept low to simplify care and to be sure all plants have similar moisture requirements.

Intensive to describe green roofs that are thick enough. Although there are no precise definitions of. You can compare an intensive roof to a normal garden and this is why an intensive green roof is also known as a roof garden or garden roof. Cincinnati civic garden center roof example rain event 12mm from july green roofs and water quantity.

A green roof with a lightweight solution of 30 kg m2 is only possible with sedum vegetation and a green roof with a weight of 220 kg m2 is composed of a combination of sedum grasses herbs or host plants. These extensive green roofs generally have 80mm of substrate. The vegetation layer consists of sedums and wildflowers. 1 extensive vegetative roofs which are 6 inches or shallower and are frequently designed to satisfy specific engineering and performance goals and 2 intensive vegetative roofs which may become quite deep and merge into more familiar on structure plaza landscapes with promenades lawn large perennial plants and trees.

They fall into three main categories extensive intensive and semi intensive. The concept of extensive green roofs is to design a rugged durable roof that requires little maintenance and no human interaction. The substrate sits on the green roof system filter sheet drainage layer protection layer. Extensive green roofs are generally made up of a very thin layer of soil or other planting medium with shallow root plants like sedum mosses and grasses.

Used vegetation consists of hardy weather resistant plants that can adapt to extreme climates. Most extensive green roofs will reduce stormwater flows on an annual basis by 50 green roofs also delay stormwater runoff but flow dynamics depend on climate and green roof design. The nominal thickness of a green roof is the approximate total height of the soil and drainage components that constitute the green roof system excluding the roof structure insulation waterproofing and plants. Roughly speaking extensive green roofs have a substrate thickness of between 4 and 15 cm and a weight of 30 to 220 kilo per m2.

An extensive green roof or sedum roof is a roof with vegetation that is more or less self perpetuating and that can further develop and maintain itself. A green roof is a layer of vegetation planted over a waterproofing system that is installed on top of a flat or slightly sloped roof. Green roofs are also known as vegetative or eco roofs.