Green Roof Roof Drainage Concepts

The guide gives rational to the whys and hows of allowing free drainage.

Green roof roof drainage concepts.

Saturation of the soil. The green roof consists of 8 superimposed layers 1 to 8. 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. Is not able to drain properly it can negatively impact the vegetation due to over.

The growing medium substrate the plant layer. The drainage capacity is tested according to en iso 12598. One of the main concerns that small scale builders have outlined to us is how to drain the roof. The most critical role of the drainage layer is to provide an adequate flow of water off the roof during and after rainfall.

How to drain the roof. The roof garden build up allows for the realisation of a variety of design concepts even waterfeatures. Green roof solutions offers many different drainage layer options depending on system goals regarding water retention. The waterproofing membrane root barrier the drainage layer.

On zero degree roofs a roof dam irrigation system can be installed which stores up to 40 mm of water. Design of drainage systems must be matched to the roof construction and catchment area. Before commercial drainage layers were developed it was common practice to use a thin layer of gravel to act as a drainage layer. Zurn is proud to introduce its green roofing drain product line specifically suited for.

These are collector drains that are designed to flow when only partly full. Primary drainage systems are not designed to remove all of the water that falls on a roof during exceptionally heavy rain. The load bearing component of the roof. This makes for lush plant growth on relatively thin substrate layers.

Having proper drainage on a green roof is a critical aspect of the system. A green roof may require a separately plumbed secondary drainage system also known as the overflow relief system.