Extensive Green Roof Construction

A general characterization of the two types of green roofing systems follows.

Extensive green roof construction.

Extensive green roof an extensive green roof system is characterized of its vegetation ranging from sedums to small grasses herbs and flowering herbaceous plants which need little maintenance and no permanent irrigation system. Extensive green roofs normally have an attractive low layer of vegetation around 80 100mm high such as grass moss sedum or small flowers. They consist of a thin layer of soil with continuous coverage of growing material. An extensive green roof is the most common and least expensive type of green roof with costs ranging from 10 20 a square foot 2.

Comparatively low capital cost. From a distance an extensive sedum roof can be mistaken for a grass field. The growing medium depth for an extensive green roof system is typically 6 inches or less. Besides the visual impact of an extensive green roof they also provide a natural habitat for birds and insects.

Green roofs which are planted and seeded tend to perform better in the long term. The most convenient green roof system type is an extensive green roof which involves a roof covering comprised of a thin layer of vegetation and growing medium that require minimal maintenance and care. Extensive roofs are lower maintenance that intensive ones and lighter in weight. For both of these we need to follow specific green roof construction and maintenance procedures.

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. These are covered with low growing plants such as evergreen sedums. They are suitable for both existing and new build roof decks. They are fairly lightweight and can be installed on roofs with a pitch from 0º to 30º.

The extensive green roof the extensive type of green roof by contrast have a soil depth of 50 150mm only support very drought tolerant plants no irrigation are too harsh an environment for most common weeds and so require very little maintenance. Green roofs consist of a number of layers including a waterproofing layer drainage layer substrate and planting. Extensive green roofs are a popular option for homeowners as they are lightweight and require very little maintenance with no need for additional watering. To start with take a look at the most simple family of green roofs.

The biggest benefit of extensive green roofs is that they need very little maintenance.