1. PASSIVE HEATING

Cost indication

Low to Med

Effectiveness rating

8/10

To be sustainable, a home needs to be built in such a way as to minimise its impact on the environment. This means constructing the home so that it works in harmony with its surroundings and uses up less resources, such as power and water, during its lifetime.

The added advantage of this is that the people living in the home will benefit in terms of reduced energy bills, making the home sustainable from the point of view of continuing affordability - that is the cost of living in the home is able to be sustained.

One of the key ways of doing this is by incorporating passive design principles into your home.

The sun is a massive source of free energy. Use it well and it can provide natural lighting in your home, warmth to heat your home during cooler months, and energy to heat your water during the warmer seasons.

Using the sun in this way is one of the key principles of passive design and it costs little or nothing to do this. It does however require planning and thought and this applies right back to the selection of your building site. You need to consider where the sun will be at different parts of the day during each season to decide where best to position your home on your section. Then the next step is to determine the layout of the various rooms in your home.

To achieve the best orientation for passive home heating, your living, family and dining rooms should face north and have plenty of large windows. It is often a good choice to have your kitchen facing east as this will enable it to benefit from early morning sun throughout the year but it will be cooler later in the day for evening meal preparation. Similarly, east-facing bedrooms will be cooler and more comfortable for sleeping, especially for children who tend to go to bed earlier.

The main additional cost that passive heating can entail is the cost of larger or additional windows. If installing skylights this can also affect the style of roof you choose which can have cost implications.

Like anything, with the sun, you can get too much of a good thing. You don’t want to save lots of energy lighting and heating your home using the sun only to have to expend it cooling your overheated home in the middle of summer. For this reason it is also important to consider shading, particularly for west-facing rooms that get low-angled sun late in the day. Shading can be in the form of trees or a covered verandah or sun-blinds. Careful placement of deciduous trees or vines can give you shade in summer to help reduce overheating, while allowing the winter sun in when you need it for heating and light.