We have chosen to use the word vegetative rather than the word green in this guide because a non vegetative roof could be considered to be environmentally green without being vegetative.
Green roof design layers.
The layers of a green roof.
You just need to build up the core layers as per manufacturer s instructions when constructing a green flat roof.
The systems are designed to ensure that stormwater can be used by plants for longer periods of time without oversaturation of the system.
A green roof or living roof is a roof of a building that is partially or completely covered with vegetation and a growing medium planted over a waterproofing membrane it may also include additional layers such as a root barrier and drainage and irrigation systems.
When constructing a flat green roof the design aspect is much simpler.
All three types of roofs require specific layers of roofing materials not found on regular roofs.
If stormwater is not properly drained it will pool and create structural risks.
Pitched green roof design considerations.
It also has plants and the like on top.
The basic anatomy of a green roof consists of vegetation growing medium filter membrane drainage layer waterproof root repellant layer roofing membrane support for plantings above thermal insulation vapor control layer and structural roof support.
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.
Layers of a typical green roof.
In short a green roof is made to purposely grow grass.
Green roofs can help reduce energy costs for a building by acting as another layer of insulation between the inside and outside of the roof.
Regardless of the depth of growing media soil and plant types used above the underlying architectural elements of most vegetated roof systems are typically the same with each layer playing a crucial role.
In some areas green roofs are installed just to create a specialized recreation place for local communities it also contributes to the establishment of habitats for various insects.
This is most noticeable in intensive green roofs since there is a thicker and more consistent layer of soil which provides a higher insulating value.
However the difference between green roofs and an actual green roof is that a green roof comes with various layers.
Flat green roof design considerations.
Green roofs are constructed by merging a number of layers over a normal roof in order to create a proper root barrier an irrigation system as well as drainage.
Green roofs are suitable for any pitch of roof.
To make this process work various green roof layers are created to give it the most effective and solid chance of being.