Building OrientationThe orientation of the walls and windows affects the amount of heat entering and leaving a home. The general rule is to orient the house so the main wall and window area face north, have minimal windows to the west and, to a lesser extent, the east.
In Australia the sun travels in the northern sky in winter. By placing living areas and windows to the north it allows rooms to be heated during the day thereby reducing the need for artificial heating at night.
Room LayoutIt's best to locate your living and outdoor areas to the north side of your home as they will be warm and sunny in winter. Minimise living areas to the west as they receive the full summer sun and will require artificial cooling to stay comfortable.
By grouping rooms of similar use together you can minimise the areas that need to be heated or cooled by using doors to separate these areas. Also rooms that use hot water such as bathrooms, kitchens and laundries should be located together. This will reduce the length of pipes used, the amount of heat lost from the pipes and allow for more efficient use of your hot water system.
Window Placement and SizingWindows are an important part of every home. They allow natural light into the home, provide views and fresh air. Well-planned and protected windows improve comfort year-round and reduce the need for heating in winter and cooling in summer. When planning your home, you should take into consideration:
North facing windows receive winter sun, allowing light and warmth into the home and can reduce your winter heating bills.
East and west facing windows receive excessive summer sun so should be kept small or be well shaded.
Shading devices such as awnings, external blinds and verandas reduce heat gain through windows in summer by 75-80%.
Glass can be treated to reduce the amount of summer heat gain, however, remember that treated glass reduces heat gain and light in winter as well.
Internal window coverings trap a layer of still air between the glass surface and covering, which reduces heat flow through the glass. Appropriate covering include drapes, Holland blinds, Roman blinds and Austrian blinds - pelmets are recommended to be effective.
In cold winter areas consider double glazing for all windows.
Use of InsulationInsulation is the most effective way of improving a home's energy efficiency and can make your home more comfortable as it acts as a barrier to heat flow - reducing the amount of warmth escaping in winter and reducing the amount of heat entering in summer. In fact, by correctly installing insulation in ceilings, in walls and under floors, you can effectively reduce heating costs by up to 50% and help to reduce green house gas emissions.
We are all familiar with the way insulation works. In summer, we keep our drinks cold by putting them in an insulated esky* - insulation in the lid, walls and floor of the esky keeps the summer heat out and ice stays solid for longer. In winter we drink hot tea or coffee from a thermos*. Again, the insulated walls ensure a hot cuppa hours after the kettle was boiled.
In homes, insulation installed in walls, ceilings and floors acts the same way, keeping heat out in summer and in during winter.
* Esky and Thermos are registered trademarks of Nylex Limited and Thermos L.L.C. respectively.
Ventilation and Draught ProofingWhen planning your home you should consider internal layouts of rooms, doorways and windows, to allow for good cross ventilation to cool your home in summer, and reduce or eliminate the need for mechanical air conditioning.
Air leakage has a significant impact on thermal performance and allows hot, dry and dusty air to enter you home. This can be minimised by draught proofing, or sealing, and gaps around doors and windows with weather stripping. The same can be said for gaps in the house construction such as along skirting's, cornices and other internal lining joints.
However, the more airtight you make your home, the more important it become to have adequate ventilation so that you maintain air quality, especially in kitchen and bathroom areas.
Building MaterialsConstruction materials such as concrete and brick can absorb and hold large amounts of heat. This heat is then released when the air becomes cooler. They have a low R-value because most of the heat from one side will travel to the other - but it takes longer then lighter building materials.
In temperate climates, tiled concrete floors and internal masonry (cavity brick, concrete block) walls assist in moderating temperatures inside the home.
Carpeting a concrete floor will greatly reduce it's effectiveness in storing and releasing heat.
In hot, humid climates, heavy construction materials provide little additional benefit and can be a disadvantage if not completely protected from the sun. Light weight construction such as brick veneer or timber/fibre-board-clad construction may be a better option.
In areas of western Queensland and where there is a cool breeze at night, a combination of heavy construction for day time living areas and light weight construction for the bedroom areas is best.
LandscapingYou can easily increase the comfort, both inside and outside of the home, and reduce the need for supplementary heating and cooling, through the careful selection and placement of plants and trees. When landscaping, you should consider:
• Tall cone-shaped trees to the southwest and southeast to reduce summer heat.
• Planting a windbreak of trees will protect your house from cold winter winds and redirect cooling summer breezes through your home.
• Deciduous trees to the north provide shade in summer and allow sunlight to enter in winter.
Essentially, landscaping is a simple and inexpensive way to improve the energy efficiency of your home, but it can also enhance the appearance and value of your property and provide screening for privacy.
Energy Efficient AppliancesThe use of hot water, efficient heating, cooling, lighting and appliances will save energy and money. As a rule, look for appliances with high star ratings - the more stars you see, the more energy you save.
Water heating accounts for up to half of your home's energy consumption. Both energy and water consumption can be reduced by installing an instantaneous gas or solar hot water system (reduces your energy consumption by around 30% and saves up to 80% on heating bills) or by doing simple things like making sure taps are turned off, installing flow regulators, using a low flow AAA shower and water efficient appliances, as well as insulating your hot water pipes.
Gas is more efficient, and produces less greenhouse gas emissions then electric hot water, so use gas where available.