Green Roof Roof Drainage Concepts

A green roof is an additional roof system on top of an existing roof made up of a layer of planted vegetation.

Green roof roof drainage concepts.

There are two main forms of green roofs intensive and extensive. The roof can provide natural substrate and processes for plant growth. System build up roof garden the roof garden green roof system is a multifunctional green roof build up with high water storage. Intensive roofs take more time to manage as they can hold up to 150 pounds of vegetation per square foot.

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. Moisture will be lost to the atmosphere as a result of evapotranspiration during dry periods. For green roofs small plants with fibrous roots and low water requirements are best suited. Integration with hard landscapes for example walkways terraces driveways or play areas etc.

Is not able to drain properly it can negatively impact the vegetation due to over. Design of drainage systems must be matched to the roof construction and catchment area. 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. The roof garden build up allows for the realisation of a variety of design concepts even waterfeatures.

As the soil takes on excessive amounts of water it continues to. The drainage capacity is tested according to en iso 12598. These are collector drains that are designed to flow when only partly full. 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.

The growing medium substrate the plant layer. Having proper drainage on a green roof is a critical aspect of the system. 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. This makes for lush plant growth on relatively thin substrate layers.

Saturation of the soil. Primary drainage systems are not designed to remove all of the water that falls on a roof during exceptionally heavy rain. On zero degree roofs a roof dam irrigation system can be installed which stores up to 40 mm of water. The waterproofing membrane root barrier the drainage layer.

The green roof can be established on any load bearing components concrete tanbark wood. The unique needs of a green roof installation. Green roof solutions offers many different drainage layer options depending on system goals regarding water retention. In addition to stormwater source control green roofs.

It is suitable for lawns perennials and with deeper growing media for shrubs and trees. The most critical role of the drainage layer is to provide an adequate flow of water off the roof during and after rainfall.