Andrew Laming (Bowman, Liberal Party) Share this | Hansard source

Often in this place, the rarefied atmosphere of parliamentary debate, many good ideas are canvassed only to meet their demise in the far more toxic substrate of state government regulation. Never was that more true than in the building regulations which are effectively formulated by each state and territory. The great tragedy of course is that, while those regulations are changing all the time, many great ideas and higher outcomes are sacrificed because local councils are unable to bring forward such great ideas as green roofs.

In Queensland, the state building regulations mandate minimum standards. If all you are ever doing is mandating the minima, so often those minima become the maximum that we see. This is the great challenge, as we consider changes to building codes. I for one would like to see higher outcomes in this area. I know that my council, Redland Shire Council, would also look to that. But that can only be achieved by encouragement from a distance through performance based codes. It is highly likely that we will continue to reflect on great ideas like green roofs by looking at what Europe may well be doing or what might be happening in the US and in Canada.

The truth is that green roofs have many direct benefits for application right here in Australia. I, as self-styled member for Moreton Bay, will speak on behalf of Brisbane, together with the member for Moreton. We both have an outer metropolitan interest in the fast-growing population that has an enormous urban sprawl. I am sure everybody would agree that, as you fly over Brisbane, there is an enormous amount of roof space per capita. Not only is this a challenge but also it is an opportunity. If the roof space is amended effectively we can look to not only reduced cooling bills in summer—and air conditioning is by far the most expensive form of power in Queensland homes—but also an amenity for the many people who work in medium- and high-rise buildings. We can reduce stormwater run-off, not so much in the city but in country areas, which is often responsible for washing away very fertile soil. By capturing a lot of that rainwater and picking up the heavy metals and the pollutants, green roofs can actually hold that water and have it returned in the form of condensation and evaporation.

There are challenges with green roofs. Of course they will be heavy. You cannot simply place one on an existing roof. The weight will often mean that a significant superstructure will be required in the roof. But for a cost of $50 to $100 per square metre what can be created is not so much vegetation but an entire ecology on these roofs, improving amenity for those who live there, evaporative cooling and a reduction in the urban heat island effect that is well described. We know that an innovation such as green roofs would reduce not only the amount of energy required to cool that building and keep the temperature stable, up to seven degrees Celsius movement due to poorly insulated roofs, but also the heat around the buildings themselves. Green roofs are just part of a great package that I think householders should be encouraged to adopt. It includes an AAA rated shower rose that reduces water use from 25 litres per minute to single-figure litres per minute. It also includes the use of dual-flush toilets—an Australian invention—again reducing water use, by 60 per cent; greenhouse energy efficient hot water systems, by putting in modern hot water systems, reducing the high water pressure that can lead to water loss with the simple use of a water-saving disc; and energy efficient lighting. We in Australia are moving very fast towards using efficient fluorescent lighting.

Green roofs come as part of a package. But, as I said in my introductory statement, it will not happen as long as our building codes, particularly in Queensland, simply dictate minima. There will be very little incentive for innovative and forward-looking councils, such as Redland Shire Council for one, to encourage these roofs, other than through basic performance based codes. We need an even greater adoption of fantastic ideas like green roofs, which have already captured the imagination of both Europe and North America.

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