Green Roof Roof Drainage Concepts

There are two main forms of green roofs intensive and extensive.

Green roof roof drainage concepts. The waterproofing membrane root barrier the drainage layer. The roof garden build up allows for the realisation of a variety of design concepts even waterfeatures. A green roof may require a separately plumbed secondary drainage system also known as the overflow relief system. Moisture will be lost to the atmosphere as a result of evapotranspiration during dry periods.

This makes for lush plant growth on relatively thin substrate layers. The green roof consists of 8 superimposed layers 1 to 8. System build up roof garden the roof garden green roof system is a multifunctional green roof build up with high water storage. The design of the different drainage layers allows for a portion of the stormwater to be retained above where the water is allowed to flow freely off of the roof.

Intensive roofs take more time to manage as they can hold up to 150 pounds of vegetation per square foot. Operating within the green roof are the interception of rainfall by the plant layer infiltration and storage in the substrate and reservoir storage in the drainage layer. It is suitable for lawns perennials and with deeper growing media for shrubs and trees. Green roof solutions offers many different drainage layer options depending on system goals regarding water retention.

On zero degree roofs a roof dam irrigation system can be installed which stores up to 40 mm of water. Saturation of the soil. A water proof layer material for water retention and proper drainage helps plant growth and at the same time protects the roof and building from damage. The green roof can be established on any load bearing components concrete tanbark wood.

Design of drainage systems must be matched to the roof construction and catchment area. In addition to stormwater source control green roofs. The load bearing component of the roof. The unique needs of a green roof installation.

The growing medium substrate the plant layer. For green roofs small plants with fibrous roots and low water requirements are best suited. Primary drainage systems are not designed to remove all of the water that falls on a roof during exceptionally heavy rain. A green roof is an additional roof system on top of an existing roof made up of a layer of planted vegetation.

The roof can provide natural substrate and processes for plant growth. Dead and imposed loads should be calculated in accordance with bs en 1991 1 1 be en 1991 1 3 and bs en 1991 1 4 and should include the weight of the waterproofing system saturated weight of the green roof components and substrate vegetation snow loads and imposed loads such as access by people and vehicles as well as point loads for. As the soil takes on excessive amounts of water it continues to. These are collector drains that are designed to flow when only partly full.

The drainage capacity is tested according to en iso 12598. The most critical role of the drainage layer is to provide an adequate flow of water off the roof during and after rainfall.