By Julie Francis.
Designing a building to stand out from the crowd is a real challenge. But green roofs and walls may just be the answer. Sometimes called ‘living architecture’ the design of gardens on hard surfaces is taking off across Australia. And developments in vertical gardens and green roofs has certainly made it a more viable option.
Green roofs and walls are often used to highlight a green ethic, for instance the Environmental Protection Agency in Melbourne has installed a green wall out the front of their building, and Melbourne Water has included a green façade in their foyer. In Sydney 1 Bligh St was greened to have a visible cue to the building’s 6 star green star rating – whilst most sustainable building features are not visible to the passerby, green roofs and walls are a notable exception.
Greening a building can have significant environmental benefits if the design caters for water re-use, biodiversity and thermal cooling. A new guide to green roofs, walls and facades explains how to design, build and maintain these structures. Whilst written for Victoria, it is relevant across the country. A new publication in Sydney is set to inspire people to incorporate plants onto buildings and shows where to visit green walls in the city.
Some of the key design considerations before embarking on a green roof, wall or façade project are:
1. weight loading capacity of the building
2. budget for maintenance
3. environmental performance expectations (is it intended that the greenery have an impact on stormwater run-off, cooling of the building, mitigating air pollution, or contributing to the biodiversity of the region?)
4. plant preferences – this will depend on climate of the site, but also on the intention of the garden – could be edible plants, or low-maintenance plants or plants that are particularly good at soaking up stormwater.
Planning for ongoing maintenance is crucial for the long term effect of the work. Most installation companies offer ongoing maintenance contracts, which takes the burden off building owners or tenants. These contracts are usually better than working with generic horticultural maintenance companies, who may be adept at maintaining garden bed plants, but not familiar with the technology and particular requirements of plants growing on roofs and walls.