Green Roof Roof Drainage Concepts

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.

Green roof roof drainage concepts.

On zero degree roofs a roof dam irrigation system can be installed which stores up to 40 mm of water. Before commercial drainage layers were developed it was common practice to use a thin layer of gravel to act as a drainage layer. Having proper drainage on a green roof is a critical aspect of the system. The most critical role of the drainage layer is to provide an adequate flow of water off the roof during and after rainfall.

This makes for lush plant growth on relatively thin substrate layers. The load bearing component of the roof. The green roof consists of 8 superimposed layers 1 to 8. How to drain the roof.

Permeability of granular drainage media for green roof systems green roofs with a purposegreen roofs with a purpose most benefits are derived from the moisture retained or circulating through green roofs thin profiles 3 inches temperate climates can achieve 90 of sought after benefits. Primary drainage systems are not designed to remove all of the water that falls on a roof during exceptionally heavy rain. The roof garden build up allows for the realisation of a variety of design concepts even waterfeatures. These are collector drains that are designed to flow when only partly full.

Saturation of the soil. A green roof may require a separately plumbed secondary drainage system also known as the overflow relief system. The unique needs of a green roof installation. The growing medium substrate the plant layer.

The drainage capacity is tested according to en iso 12598. Green roof solutions offers many different drainage layer options depending on system goals regarding water retention. The guide gives rational to the whys and hows of allowing free drainage. Is not able to drain properly it can negatively impact the vegetation due to over.

The waterproofing membrane root barrier the drainage layer. The green roof can be established on any load bearing components concrete tanbark wood.