Garden up top
They’re aesthetically pleasing, environmentally friendly and offer green outdoor space to urban concrete jungles. Green roofs are finally gaining popularity in the residential market.
The concept of the garden roof top is hardly new. In fact, even the methodology is hardly new: soil and vegetation are supported by a sophisticated system of layers placed over the roof which waterproof, drain, filter and repel roots. This concept was developed in Germany in the 1960s and soon spread to other European countries thanks to government financial support and legislative that recognised the public benefits of green roofs. In Germany, France, Austria and Switzerland there is now a multi-million dollar market for green roof products and services.
In Australia, the uptake has been much slower. However as we move to a greater reliance on multi-level living, and feel the pressures of environmental concerns and rising energy costs, the concept is gaining momentum.
“There has been a fear of additional costs incurred, no question,” explains Adrian Fratelle, director of the Fratelle Group.
“Green roofs are more expensive than a standard roof construction, so a client will want to see some return from investing in a roof garden that goes beyond just aesthetics.”
The Fratelle Group is a full service architectural and design practice operating out of Western Australia and recently designed a home with a green roof that will commence construction in Burns Beach early next year. The energy savvy designer was thrilled to have a client keen to push the envelope in terms of green aspects to the home.
“As electricity prices continue to soar, many people are beginning to realise the initial investment that goes into a green roof will result in huge long term energy savings,” he says.
“There are some additional challenges when it comes to green roofs, namely our long hot summer and strong winds. However, arid countries like Spain are showing the concept absolutely can work in this environment. We’re taking a lot of our cues from Spain, as an important element is finding correct planting for green roofs that will survive. There are a large variety of plants you can use that don’t require a lot of water – succulents are a good example.”
The reasons to consider a green roof are far more than aesthetics. They improve air quality by capturing airborne pollutants and filtering noxious gases, reduce electromagnetic radiation penetration by up to 99.4% and absorb noise pollution. They also provide nesting nooks for our feathered friends.
Adrian is confident that it’s only a matter of time before Australia cottons on to the benefits of green roofs in residential design.
“Green roofs keep energy costs down substantially and, as we move toward six and eight star ratings in the future, it makes sense we will see a lot more of them. And the bigger the increase, the more they will go down in cost,” he says.
Furthermore, smaller lot sizes and more high-rise dwellings will also result in an increase in green roofs.
“As more roof areas are visible from upper floors, it’s important to have structures that are aesthetically pleasing,” he adds. “And lifestyle-wise, people are also looking at green roofs as an accessible place where you can sit and enjoy the sunshine on a tight block or grow vegies on your roof.”
The specific project Fratelle is undertaking will be monitored closely, as the coastal location of Burns Beach provides a good test for the green roof.
“The home is very exposed,” he says. “One of the critical things when designing a green roof in Perth is that wind exposure is quite prevalent in a lot of areas. So you need to make sure the green roof stays where it is meant to stay and the type of plants selected need to be able to tolerant the wind and salt spray.”