That's literally hundreds of dollars a month going out the window, and a needlessly large CO2 footprint.

Single glazed windows are notoriously poor at any insulation as single glass panels transfer cold very easily reducing the temperature inside, thus requiring a greater amount of energy to maintain a comfortable temperature.

The answer is to double glaze windows.

High performance double glazing can reduce heat loss by up to 73%, and make for a warmer, drier, healthier home for you and your family. Double glazed windows will help keep generated heat inside, keeping the home at a more consistent temperature – cutting down power costs and reducing the need for expensive, view-blocking drapes.

Double glazing also helps reduce "crying windows" in winter. Condensation or crying windows forms when warm moist air meets a cold surface such as glass. Double glazed units are warmer, and therefore less likely to attract condensation, than a comparable single glazed window because it is insulated from the outside air.

Metro GlassTech is New Zealand's largest and most trusted supplier of Metro-fit double glazing and offer advice on double glazing for both new and existing homes.

"Many New Zealanders, when they are building or renovating, do not realise all the options available to them with glass colour, tints, thermal efficiencies, sound proofing and safety glass. We have a team of professionals on hand to help provide advice to ensure you get the product which best serves your needs," says Metro GlassTech's Darryl Mac.

Metro GlassTech can offer a variety of insulation solutions for windows by incorporating Low E and Argon gas which enhance insulation performance. Metro-fit double glazing leaves your home virtually unchanged yet you enjoy all the benefits of double glazing.