We are bombarded these days with talk of energy efficiency in our homes and buildings, but do you really know the basics? Here are the principle tenants of designing an energy efficient home.
BASIX. The Building Sustainability Index (BASIX) is the energy efficiency legislation in New South Wales that requires all residential buildings to comply with minimum benchmarks in various areas relating to energy efficiency. Don’t blame Council- this is state government legislation with which all residential projects in NSW must comply.
Thermal Comfort. This is the first BASIX category. It relates to the means by which we can keep you comfortable inside your home, making it less likely that you will switch on the heating or cooling. There are several methods that go towards achieving a good level of thermal comfort:
– Orientation. Where possible, keep the long axis of your home’s living areas facing north, and minimize your window areas to the west and east (where heat gain is a problem in the summer) and the south (where heat loss occurs in winter).
– Thermal Mass. Creating a thermal mass that the sun can get to during the day in winter will allow it to then release that heat back into the house at night. A thermal mass can be obtained by building on a concrete slab or exposing masonry walls inside.
– Glazing. If you can, install double glazed windows. These will very effectively retain the heat in the house in the winter. For summer consider some kind of external shading. This can be a pergola with a deciduous vine or a retractable awning.
– Insulation. Utilise insulation everywhere that you possibly can- in the walls, under the floor, above the ceiling, under the roof- to ensure that your home is wrapped in a warm blanket. Avoid gaps!
– Roof Overhangs. It is important to ensure that every north, east and west window in your home is shaded by an eaves overhang. In the Southern Highlands an overhang of about 60 or 70 cms will block the higher angled summer sun while still allowing in the lower angled winter sun for the best of both worlds.
Energy. This is the second BASIX category. Ensuring that your home draws as little power as possible will not only be kinder to the environment and our natural resources, but also to your hip pocket as electricity prices soar. The use of low energy light globes, natural methods of drying clothes, air conditioning systems with high star ratings and a low energy hot water system (such as solar or heat pump) will gain you a good score for energy use.
Water. This is the final BASIX category. Gone are the days when Councils did not allow the installation of water tanks- for new homes it is now mandatory for new homes. Other methods of conserving water in your home include installing highly rated taps, showerheads, toilets and appliances (washing machines, dishwashers), collecting water from your entire roof and reusing it not only on the garden but for your laundry, toilets and other outlets in the home, and collecting and reusing grey water from the sinks and washing machine.
