Extensive green roofs: near-natural vegetation with minimal effort
What is extensive green roofing?
Green roof types refers to the basic design and use of the green roof. Extensive green roofs" are those with a simple structure and low maintenance and use. The opposite is "intensive green roofs" (roof gardens) with a higher, garden-like structure and correspondingly higher maintenance and use by people as additional living space.
Why extensive green roofs?
Extensive green roofs promote biodiversity. The plants bind fine dust from the air and green roofs are a good buffer for rainwater run-off. A green roof also acts as a natural air conditioning system.
Structure
The appearance of extensive green roofs is similar to that of natural unused areas. The height of the green roof layer structure is around 5 to 15 cm, the weight around 50-170 kg/m² (0.5-1.7 KN/m²). Extensive green roofs are possible on flat and pitched roofs with an inclination of up to 45 degrees.
Costs
Extensive green roofs are intended as an ecological compensation for overbuilt nature. They are subject to the natural and seasonal development of vegetation and the transformation of existing vegetation. The standard costs for extensive green roofs are around 15-40 euros/m², depending on the green roof structure and the size of the area.
Plants
Low-growing plants (mosses, succulents, herbs, grasses) are used for low green roof structures, which are largely self-sustaining and continue to develop with little or no maintenance. They are adapted to the extreme site conditions on the roof (extreme temperatures, frost, wind).
Substrates
All Optigreen substrates are optimally matched to our system structures and thus guarantee the long-term functionality of your green roof system. The following Optigreen basic substrates are suitable for "classic" extensive green roofs:
- Extensive single-layer substrate light M/l
- Extensive single-layer substrate heavy M/s
- Extensive multi-layer substrate light E/l
- Extensive multi-layer substrate heavy E/s
Light and heavy substrates differ in appearance due to the different aggregates and weight. Light substrates contain light aggregates such as expanded clay. The heavy substrates contain heavier components such as lava or brick chippings.
All substrates comply with the FLL green roof guidelines, ÖNORM L 1131 in Austria and the Fertilizer Ordinance. Here you will find an overview of our Optigrün substrates.
Extensive green roofs
Examples of our system solutions for extensive green roofs are:
Economical roof
The name says it all with the low-cost roof: an inexpensive, sophisticated and highly functional type of green roof.
Lightweight roof
The 'slim' roof structure is ideal for renovating older roofs without structural reserves. Even large industrial roofs in lightweight construction can be used as compensation areas.
Nature roof
The natural roof is a great way of preserving biodiversity in the long term, even in cities. On the one hand, we leave our children a natural environment worth living in and, on the other, we beautify our living space and increase the quality of life.
Retention roof Meander 30
A retention roof offers the most efficient way of slowing down runoff while at the same time having a high ecological value.
Pitched roof
The greening of pitched roof surfaces is the supreme discipline for roof greeners. Thanks to decades of experience and development, we can choose from several innovative system components and work out optimized solutions together with sound load calculations.
Solar green roof
At a time when climate change and the energy transition are discussed almost daily, the SOLAR GREEN ROOF is the perfect combination of various tools for solving these future issues.