In response to record-breaking heat across the country throughout 2013[1], and in the first weeks of 2014, The Association of Building Sustainability Assessors (ABSA) has flagged five simple and practical summer design tips for a more energy efficient and sustainable new home.

“Heating and cooling accounts for around 38% of household energy use and 20% of carbon emissions from a typical Australian home but by carefully planning and designing your new home, you can dramatically reduce the need for artificial heating and cooling, saving hundreds of dollars a year and making your biggest investment more naturally comfortable during summer,” Sid Thoo, ABSA’s Chairman said.

Before your home design is finalised or better still, before you even talk to your architect, building designer or home builder:

1. Know where the sun is coming from: by understanding the position of the sun in relation to your building, you can design the rooms of your home to help keep out unwanted summer heat. Generally windows facing toward the north in your main living areas will provide plenty of natural daylight, without allowing too much direct sun to enter into the space. Allowing the roof to overhang the external walls by around 500-600mm will ensure that no direct summer sun will enter, helping to stop your house from overheating.

2. Choose light reflective colours for external surfaces, especially the roof: light colours help to reflect solar radiation, whereas darker colours absorb more solar radiation – if you had two identical houses, one roof dark and the other light, the air conditioner in the dark roof house would have to work up to 20% harder to keep the house cool. Try to avoid bare metal finishes such as galvanized roofs – these reflect a lot of visible light, but can create unpleasant glare, and actually don’t reflect as much infrared radiation from the sun, which is what causes your house to heat up.

3. Make sure you have the right insulation in the right places: it’s most important to have the right levels of ceiling and roof insulation in place, as a lot of summer heat can enter through the roof. Bulk insulation such as fibreglass batts, and blow-in newspaper is best for the ceiling, while reflective insulation such as building foil and sarking, works best on the underside of the roof covering.

4. Position windows and doors to maximize natural ventilation: most of our capital cities are located near the coast, where the difference in temperature between the land and sea often creates cooling afternoon breezes to blow in from the coast. If you place doors and windows with security and flyscreens in the right places in your rooms, you can use this free air conditioning to help cool down your home. The type of window opening also makes a big difference – casement and sliding windows provide more ventilation than awning windows.

5. Have your new home design assessed by a qualified Nationwide House Energy Rating Scheme (NatHERS) assessor before you finalise your home design: specially trained NatHERS Assessors can simulate the thermal performance of your new home and help you make good design decisions before the plans and specifications get locked-in. Simple design considerations that add little or no cost to your building will reduce the need for artificial heating and cooling, and help make your home more naturally comfortable. NatHERS Assessors can help you choose the best building materials and right types of insulation, save money and also add value to your new home.

Most new houses in Australia have to meet a minimum six out of ten star energy rating; by getting an experienced Assessor to provide advice in the early stages of design for your new home, you can achieve even higher star ratings without adding considerably to the cost of the build, and giving you a better home.

“With what we now know about the effects of a changing climate, it’s vital we improve our housing stock and future-proof it against rising energy demand and costs – the design and construction of energy efficient housing is critical for all Australians,” Rodger Hills, ABSA’s CEO said.

-ENDS-

Sid Thoo is the new Chair of ABSA and a practicing architect based in Perth who helps people design eco-effective homes that are more comfortable, use less energy and water, and have a smaller carbon footprint. He lectures at Murdoch University in energy efficient building design and is a member of the Australian Institute of Architects.

About ABSA: The Association of Building Sustainability Assessors (ABSA) is a not-for-profit national membership organisation representing building and design professionals who specialise in assessing the environmental impact of buildings. ABSA’s vision is to improve sustainability through the design and use of buildings.

For more information about ABSA visit www.absa.net.au