Sydney trials of extensive light weight green roofs over a 3 year period. In Berowra and Kemps Creek near the new airport in Sydney.
I have since added a number of photos from the successful trials. Urbanscape growing media proved to be a great part of the success. With roofs this light and thin, we have no excuse to not provide a green canopy to all our cities!
Contractor: Evolvement Pty Ltd rob@greenlook.com.au
Researcher: Robert Griffith BEnvSc +61 468 787 071
In May 2017 we set about building a series of experimental light weight green roof to test native and exotic plant growth, we determined weights for roof construction and measure reduced stormwater peak flow rates, irrigation requirments and plant species success.
The purpose of the roof is to help Evolvement provide effective green roofs to help you to meet sustainable targets and costs for your home or business premises.
We completed the installation of the green roofs. 20 different test panels 1200x1200mm in size with a variety of treatments and species. All but control panels had Urbanscape and soil, Soil depths varying from 15mm to 100mm depths.
Fully saturated weight varied from 64kg/M2 up to 200kg/M2. All considered light weight extensive green roofs.
Plant species varied from exotic and native succulents to native and exotic shrubs commonly specified by Landscape Architects. Although the succulents performed better in the more shallow panels, all plants performed well with the addition of Urbanscape.
Green roof growing media is a mixture of 70% various inorganic and 30% organic material with 100 grams of 18 month slow release fertiliser for each 1200x1200mm panel. Urbanscape was in the form of Greenroll 20 and 40mm depths.
Irrigation rates were reduced when Urbanscape was part of the growing media profile, as Urbanscape holds 85% of its volume in water.
During these trials Evolvement has learnt a lot about the value of green roofs. Our partners in Europe (Knauf Insulation) and the USA (Sempergreen and Green Roof Diagnistics) have developed the Purple roof concept for storm water detention. This eliminates the costly stormwater detention tanks. This will reduce the Urban Stream Syndrome problem around your development site. We have designed a number of green roofs for biodiversity habitat. We have developed software for engineers and developers. Products and assistance are available Australia wide for your projects.
Happy green roofing.