Very little energy is needed to make a well-designed house comfortable. Appropriate insulation, which is essential for a comfortable house, combined with passive solar design and a draught-proofed building, can create low or even no energy requirements for heating and cooling. Highly efficient homes with no heating or cooling input are possible across much of Australia.
Even for existing homes there are many ways to reduce energy bills, improve comfort and help the environment. The principles of thermal comfort and the importance of air movement, humidity and radiant heat are explained in the section Passive design.
Projected average home energy use in 2012 — actual energy use varies from state to state (particularly with climate) and from home to home depending on the heating and cooling systems in the home and how they are used.
Use passive design principles to increase comfort and reduce the need for heating. Insulate the roof, walls and floor, seal off draughts, let in winter sun and draw curtains at night. Zone your existing or new home and only heat the rooms you are using; use doors to prevent heat escaping into unused rooms (see Passive design).
The two main types of heating are radiant and convective.
Radiant heaters predominantly heat people and objects by direct radiation of heat. Convective heaters warm and circulate the air in a room.
Other forms of heating, such as heated floors, also heat by conduction through direct contact.
Different forms of heating are best in different circumstances:
- In larger rooms with high ceilings, a combination of radiant and convective heating is best.
- In small rooms, space convective heating is effective.
- In larger draughty rooms or bathrooms, radiant heating works best.