Green Roofs

Green Roof Growing Media Specialists

Create usable green space, reduce urban heat island effect, increase value of high rise building space and manage storm water runoff.
The Hills BARK BLOWER trucks supply and install growing media for new and retrofitted green roofs.

The Hills BARK BLOWER company is involved in the development of the green roof industry in Australia. There is a list of environmental benefits to establishing the practice of green roofs in Australia. Listed below are a few points outlining why The Hills BARK BLOWER is investing a great deal of time and money developing our best practice for this specialised green industry.

How to install a Green Roof **

1. Start with a clean roof and clear drainage points
2. Calculate the load holding ability of the roof - engineers and architects will often have this information and it is worth ensuring the overall weight of the system can be upheld by the roof structure, especially when retrofitting roofs.
3. Waterproof the roof/ lay membrane - ensure it is carried out by a professional and that the waterproofing has dried (or cured) properly.
4. Test the waterproofing - the most common failure for greenroofs is that the drainage and waterproofing has not been installed correctly.
5. Lay Drainage Cell - this item encourages correct water and air flow in the roof ecosystem. It inhibits water logging and fungal growth.
6. Lay a filter layer most commonly in the form of geofabric.
7. Install Green roof media such The Hills Green Roof mix. Ensure it has been tested to enable plant establishment as well as structural longevity. In Australia, best practice  includes a percentage of organics in the mix to counter the spread of fungal disease, assist in water retention (due to low rain fall), and encourage a healthy microbial ecosystem. The inorganic component must display a light Saturated Bulk Density and longevity.*
8. Install irrigation 
9. Plant the plants and add mulch for lower roof tops and mesh if the roof is higher where the wind may be a factor. There has been quite a bit of local research into best plants for a green roof. Keep in mind the following: availability, visual amenity, regional weather (sedum is by no means the most appropriate plant variety for green roofs), and maintenance schedule.

Green roofs can become a successful ecosystem when established properly.
*If the roof is contoured dramatically, it may need some flexible cells to hold the plants and media stable until establishment.
** This 'how to' information is based on information from the City of Sydney: Green Roof Resource Manual, Soils for Landscape Development - Leake and Haege. The above methodology is a suggestion only. It has been used to install larger roofs across the Sydney region for many years and it is suggest the Landscape Architect plans need to be adhered to when undertaking the build.

 

High density living has created less and less green space for community interaction. Green roofs can offer the opportunity for new recreation areas in population dense environments where traditionally there was little available.

The Urban Heat Island Effect is when large buildings heat up during the day and radiate the heat at night to create artificial hot spots in the warmer months. It is most noticeable in built up areas. Construction materials consist largely of materials that store heat and create this problem.

Research has indicated that there is a significant drop in temperature if even a small proportion of buildings in dense areas have a green roof.

Storm water runoff is reduced and filtered with an increase of green space. Water management is a high priority in Australia and green roofs offer another opportunity to catch and reuse grey water in built up environments.