Keeping cool
Air conditioning is not an essential requirement to keeping your home cool in summer. By using passive cooling techniques you can keep the temperature of your home down.
Passive cooling
To keep heat out of your home, keep your windows and doors closed during the day. Recreate air flow in the house using a ceiling fan or a standalone fan. These use much less energy than an air conditioner. You can also hang a wet cloth or sarong in front of the fan or in a window to create a cool breeze.
Then make the most of the cool change in the evenings – open your windows and doors and let in the cool breeze! As our cool changes generally come through from the south, any doors or windows you have facing this direction will be worthwhile opening at night. By opening doors and windows opposite each other you can get cross ventilation. Since the cool change often doesn’t come through till late evening, it may be worth investing in some locks to secure windows in an open position and fitting security doors to exterior doors.
Windows
Another way to reduce heat in summer is to shade your windows. Heat is transferred into the house as soon as the sun touches the glass so external window protection is the most effective way to prevent heat gain. Exterior window protection such as adjustable blinds, awnings and shutters are an excellent way of providing shade in summer, and have the flexibility to bring the sun in when you want it. The highest priority for external blinds is full window shading on west windows (pull down blinds to block low afternoon sun) and blinds or correctly designed eaves to block the high summer sun on north facing windows. However, the more windows which do not receive direct light during summer the better. Simple shade cloth blinds are excellent as they let in light but keep the sun’s heat off the window.
Plants and trees are another option for shading. In Melbourne we need the winter sunlight to warm our homes so consider planting deciduous plants which are green and covering in summer but do not block the sun in winter when they lose their leaves. A vine on a trellis outside the window is a practical and attractive example of this.
Cooking
Avoid using heat producing appliances during the hot parts of the day. Stoves and ovens are particularly good at heating up rooms and the people in them. Cook when it is cooler, cook outside or enjoy cold meals.
Insulation
Insulation helps you to stay both warm in winter and cool in summer. Up to 60% of heat entering your home comes through ceilings and walls so insulating your roof will stop the heat transfer from the roof into your home. Ensure you have both bulk and reflective insulation in your ceiling. Make the most of the current insulation rebate when getting ready for the hot summer days. For more information on the rebate have a look at
www.environment.gov.au/energyefficiency/insulation.
Air conditioning
If you do need to use an air conditioner, select an energy efficient model (www.energyrating.gov.au) and make sure you avoid using it all day, switch it on only when it is necessary. Set your thermostat between 24 and 26 degrees as each degree below 24 will add 10% to your cooling bill. If you have to wear socks and jumpers to be comfortable it is time to turn your thermostat down! Don’t air condition unused rooms, and keep the cool rooms closed. Keep your air conditioner well maintained to lower running costs and increase efficiency.
