Building a truly sustainable home takes a certain amount of vigilance and scrutiny. Here, our resident eco-building guru Jan Brandjes shares his thoughts on how to ensure future housing ticks all the environmentally friendly boxes.
A seasoned construction and building specialist, Jan Brandjes, possesses years of experience in sustainable and eco-living. He is a regular contributor to publications including the home improvement pages of Melbourne paper The Herald Sun.
Recently I developed a theory on the current energy efficiency of our new homes.
In spite of new building regulations in place over the last decade to ensure that new homes are more energy efficient than those constructed since World Wars I and II, our homes are consuming more energy then ever before.
Is it that we are building bigger (but not always better) homes, or is it that we fill them up with electricity and gas guzzling appliances? I personally think that these two factors play a big role in our quest for more energy. Bigger homes do require more energy for heating and cooling – that is if we want to keep them comfortable to live in. And it doesn’t help if we keep decorating almost every room with a on-the-wall plasma or LCD TV.
There is however another issue that deserves our full attention, and that is the matter of quality of construction. I am not talking here about the structural quality, or the finishing quality of the house. That is well looked after by the industry. I am referring to the quality of construction in the area of energy efficiency.
Let me give you an example: According to the energy ratings report of FirstRate 5, a house needs to be insulated with R1.5 batts in the walls and R3.5 batts in the ceiling. It is expected that the insulation installer will fill the walls and ceiling without leaving any gaps. Leaving gaps will dramatically reduce the efficiency of the product: 5% of surface area missed will result in a 50% reduction in efficiency!
The building surveyor will return to the house for a final inspection, but will not always have the opportunity to inspect the insulation job. This is a quality control issue and should be addressed.
Here is another example: The builder has installed double glazed windows, as specified in the energy ratings report. However, when the painter came to paint the doors, he removed the weatherstripping to do a better job. The weatherstripping was stored in the garage and were never put back on the doors ( the cleaner threw them out). Energy will always leave the building through gaps and cracks. No amount of double glazing will prevent the energy loss in this case.
So here is my theory:
a2 + b2 = c2. ( I do realise that I am not the first to came up with this, I think his name was ‘Pythagoras of Samos,) ‘a2′ stands for sustainable design. This we do very well and is supported by the energy ratings software. ‘b2′ stands for sustainable construction. This deals with the quality control of the energy efficiency measures we’re putting into the building. And finally ‘c2,. This is the best sustainable outcome: a truly energy efficient home. So, without the ‘b2′, we will continue to fail in achieving a sustainable outcome. The construction industry must come to grips with this and act without delay!