Keeping Heat In Your Home
Heating a home raises the temperature, but insulation is necessary to keep the house at a healthy temperature for a sustained period of time. Broadly, retrofitted insulation can be installed in the ceiling cavity, in the walls and underfloor. Ceiling insulation is a good starting point, as it’s usually the simplest job and prevents the loss of energy as heated air rises. If your budget extends further, consider looking into underfloor and wall insulation. It is possible to retrofit wall insulation, but not for all wall types.
Of course, insulation will not prevent heat loss through windows and glass doors. A standard, uninsulated exterior timber-clad wall may have a thermal insulation rating (or R value) of as low as 2.0, meaning that there is very little resistance to thermal escape. Insulation can bring this R value up as high as 7.0, well in excess of the current minimum standards in the building code. In contrast, a single glazed window may have an R value as low as 0.15. Double (or triple) glazing essentially insulates windows; either air or a heavy gas such as argon is trapped between two window panes, reducing the amount of heat that will pass through the window (potentially beyond an R value of 0.5 for high performance double glazing). Double glazing can be expensive, although it may not be necessary to do every window at the same time. In the meantime, you should make sure to cover any single glazed glass with a thermally lined curtain, which will have a similar effect.
Once your home is geared to keep the heat in, the cost to heat it should be much lower. Using an energy efficient heating source will reduce the heating bill even further. For most homes, a heat pump will be the best value option; a higher upfront cost is offset by years of lower energy use. Heat pumps heat space quickly, which also makes it practical to heat a specific area of the house when you need it – rather than running the appliance throughout the evening.
Excess moisture effectively increases the cost to heat or cool your home. Releasing less moisture into the air will help keep your home dry, reducing the need to use a dehumidifier or heat pump.
For most households, cooking and showering are the largest sources of moisture. Many homes have a stovetop vent, although these are often too small to cover the entire cooking space – the vent should be larger than the stove space so that most steam is captured. For houses with cold bathrooms, sealing the shower (using products such as a Showerdome) can prevent windows and mirrors from steaming up. Sealing a shower also keeps the space much warmer, meaning that you can comfortably shower at lower temperatures throughout the year.
Taking Load Shifting to the Extreme
Heavy energy users (such as owners of electric vehicles) usually take advantage of off-peak energy rates to keep electricity bills down, and there’s no reason lighter users can’t do the same. By shifting electricity use to off-peak times (such as after 9pm or between midnight and 4am) it is possible to pay less for the same energy usage.
It may seem like a hassle, but shifting a large part of your household electricity usage to off-peak rates simply requires a little forward planning. Running energy intensive appliances like clothes dryers and dishwashers overnight is simple – most appliances come with timers, and older models can often be used with a plug-in wall timer. Extreme early birds or night owls might even consider cleaning the house off-peak. Some providers (such as Electric Kiwi) even offer free off-peak power; if you can shoe-horn 15-20% of your usage into the free time slot, the savings can be significant.
Keep Hot Water Costs in Check
Reducing the temperature your hot water cylinder runs at is one of the simplest ways to make your home energy efficient – it’s an easy DIY job and won’t cost anything to do. Hot water accounts for 30% of the average household energy bill, so getting it right can significantly reduce your power bill.
If your hot water needs vary wildly (for example, in a holiday home or if you regularly have guests), you might consider installing a continuous-flow hot water heater. Water is only heated as it passes through the unit, meaning you won’t pay to keep an unnecessarily large cylinder heated throughout the day.
Whether you’ve got nothing to spend or you’re ready to renovate, there’s plenty you can do to make your home healthier and more energy efficient this winter. For more ideas, check out the EECA Energywise website – and for more home and living inspiration, subscribe to our Making It Happen newsletter.