After an Indian summer New Zealand has been hit hard in the first round of winter weather.

Community Energy Network chief executive Jo Wills says efficiently and cost-effectively heating homes is a big problem in New Zealand, caused by substandard houses, moisture, and the high retail cost of power.

Hundreds of thousands of low-income families in New Zealand are living in "fuel poverty", where heating their home to the World Health Organisation standards of at least 18 degrees Celsius for adults eats up more than 10 per cent of the household's income, Wills says.

The energy bill in an average household of four is about $2800 a year, and 35 per cent, or $980, is heating.

With retail energy prices more than doubling during the past four years, Kiwis are looking for ways to heat their houses without sending the power bill through the roof.

There are ways you can warm your home in a more cost-effective manner.

INSULATE

According to the Energy Efficiency and Conservation Authority (EECA)about 700,000 New Zealand homes have inadequate insulation.

Good-quality, well-installed insulation can significantly reduce the rate of heat loss in your home, making it easier and cheaper to heat.

Wills says a lot of those living in energy poverty live in houses without insulation.

"It does not matter how much heat they pump into the house, if it isn't insulated it won't hold the heat, and the electricity bills will keep increasing."

Auckland residents Alice Murray and Elspeth Hoskin live in a Kingsland flat with two others, and have taken measures to trap the heat in their uninsulated house.

The weatherboard home is more than 100 years old, with wooden floors and draughty doorways. The group bought pillows to stuff up the old chimney.

It costs just over $3000 to insulate an average pre-2000 home.

The Government's Heat Smart programme has helped insulate 215,000 homes since 2009.

A new insulation programme worth $100 million over three years was announced in the Budget, and will insulate 46,000 houses.

Lined curtains also help, and should be closed by dusk to trap in heat. If you can't afford curtains, the Community Energy Network runs nationwide curtain banks.

Draught stoppers, even something as simple as a towel stuck under the door, will help keep the heat in.

Widia Soedjanto has lived in her Wellington home in Churton Park for the past 14 years.

The house she shares with her husband and two children was built in the early 1980s and has little insulation, and no double glazing.

Her hubby put in under-floor and ceiling insulation a few years ago, but the house is still draughty.

If you live in a particularly cold part of the country, consider double glazing. However, it is expensive, costing anywhere from $5000 to $40,000, depending on the size of your house and the type of glazing and frames you want.

Window film is a cheaper alternative for about $20 for a two-window kit, and available at hardware stores.

HEAT PUMPS

Heat pumps are becoming increasingly popular and, if they are the right size for your home, they can be very efficient.

A new heat pump will set you back between $1500 and $3500.

Make sure your heat pump is "Energy Star qualified" as they are more efficient, the EECA says.

For example, a heat pump running for about six hours a day, six months a year, with a three-star rating will cost about $532.60 a year, and use 2030 kilowatts of power an hour.

HEATERS EECA

senior technical adviser Christian Hoerning says New Zealanders have learnt not to pump enough heat into their homes.

"Regardless of what heating device is being used, in many New Zealand houses not enough heating energy is being used because when people do pump heat into their houses it is lost because of cracks and poor insulation."

So Kiwis need to heat their homes more, but what's the best appliance for the job?

It's important to select the right size and type of heater for your home.

Luckily, most portable heaters do pretty much the same job when it comes to efficiency.

Portable electric heaters are good for heating small, specific spaces like bedrooms and studies, the EECA says.

The Kingsland flat has three new ceramic wall heaters. They cost $100 a pop, but heat the room for only 4 cents an hour.

"I had to get out of bed to turn it off the other night, it was so hot," Hoskin says.

The EECA recommends buying Energy Star qualified heaters. These will set you back between $40 and $900.

Soedjanto says while her heating appliances are effective, there are still quite a few draughty spots.

This could be part of the reason the family's power bill is about 40 per cent higher during winter.

Soedjanto has a gas heater in the living room that is timer activated, so it's only on when it needs to be.

The family of four also have a gas heater upstairs, but it is unflued so they rarely use it.

Avoid portable gas heaters, because they are the most expensive heat source, the EECA says. They also release moisture and noxious gases.

Modern wood burners are energy efficient and environmentally friendly. They also reduce the amount of moisture in the house, and produce less smoke when burning dry wood, Wills says.

About 30 per cent of New Zealand homes suffer from moisture problems.

Murray and Hoskin live with an asthmatic flatmate in an old house that's prone to dampness. They swear by their dehumidifier. Its use has not increased the power bill during the past few months, they say. The flatmates leave the appliance in the bathroom, where it helps dry their towels.

"It uses less electricity than it would if you used a dryer," Murray says.

Soedjanto says her house has definite moisture problems.

"Crying windows are a nightmare."

She puts towels on the window sills to absorb the moisture.

She also has to cook with the windows open, as there is no rangehood over the stove to collect the moisture and smoke from cooking.

HOT WATER

Hot water heating accounts for about 30 per cent of energy bills and costs the average household about $650 a year.

For a typical household on mains pressure, an efficient shower head could cut hot water use by about 25 per cent, cut the energy bill by about $160 a year, and reduce water bills, if you're on metered water.

Another way to boost efficiency is to wrap your electric hot-water cylinder and insulate your pipes.

Wraps cost about $60 a metre, and pipe insulation about $5 a metre from hardware stores. If you have an old cylinder and pipes, this could save you up to $80 a year.

And make sure you turn on your heated towel rail only when you need it. This can save you about $120 a year.

AT NIGHT

According to WHO standards, children need to live in a house heated to at least 20C, 2C warmer than the standard for adults.

New Zealand needs to follow the example of European and Canadian houses, Soedjanto says.

There are also the traditional options of hot-water bottles or electric blankets. Hotties will set you back between $5 and $10. However, the hidden cost is in boiling the kettle, which can cost up to 45c each time.

Electric blankets are another option. For a queen-sized electric blanket, you're looking at between $40 and $80.

For more energy-saving tips visit the EECA website, energywise.govt.nz