Green roofs transform the grey urban environment into a living space where people, animals and plants can interract. Green roofs while collecting and absorbing the fine dust are increasing the efficiency of insulation and are protecting the roof structure while returning a part of urbanised surfaces back to nature. Even if the green roofs are implemented at ground level, being well-tended they can offer joyfull green areas, and are allowing to track nature’s changing colours from one season to the next one.
A green roof or living roof is a roof of a building that is partially or completely covered with vegetation and a growing medium, installed over a waterproofing membrane. It may also include additional layers such as a root barrier filtering fleeces, drainage materials and in some cases irrigation systems.
Generally, green roofs serve several purposes for a building, such as absorbing rainwater, providing insulation, sustaining biodiversity, and helping to lower urban air temperatures and preventing the heat island effect. There are two types of green roofs: intensive green roofs, which are thicker and can support a wider variety of plants but are heavier and require more maintenance; and extensive green roofs, which are lighter than an intensive green roof mainly due to a thinner growth substrate and a light layer of vegetation which provide a meadow effect, and requires only low maintenance. Basically both green roof systems consists in protection fleece, drainage layer, filter fleece and growing media for dhrought – resistant plants.
Moreover, green roofs offer thermal and noise insulation and comprehensive protection against vibrations caused by machinery, trains, plains etc.; and they simultaneously act as a collecting system that retain rainfall and snow. The extensive roofs with a large surface area form a protective environmentally friendly layer, and are recommended for architectural structures with limited sustainability. They are furnished with hardy plants capable of flourishing even in extreme weather conditions, requiring minimum care and attention once they have reached maturity. Roof gardens protect roof structures from extreme temperatures, hail showers and other forms of extreme weather, doubling their lifespan. The increase in the amount of moisture evaporating into the surrounding air creates a cooling effect in the summer, making the air less dusty and even helping reduce pollution.
For additional informations and green roofs normatives please access www.fll.de.
Principal Green Roofs components:
Is a water drainage and reservoir board made from heavy duty polystyrene. The surface is shaped on both sides and perforated on the top.
Substrate / soil
A loose mainly mineral substrate with good drainage properties and low organic content.
For extensive green roofs the vegetation is mainly composed out of succulent plants wich can function and accrete long term. These kind of plants are most suitable to live on an extensive green roof duet o the fact that they are light weight and do not require a thick layer of substrate.