Watch wasteful windows

Windows are a source of heat gain in summer and heat loss during winter. The most effective solution? Install a ‘buffer’ against heat transfer.

Changes to windows or balcony doors with double glazed windows and doors require approval from the owners corporation, however, there are lots of other great actions you can take which don’t require owners corporation approval.

Below are some of our favourites.

Install thick curtains or blinds.

Thick curtains and blinds act to trap a layer of insulating air between the window and the rest of the room. This can prevent heat loss by up to 40%. Even if you already have curtains, adding extra lining or buying thicker curtains will make a real difference to how warm your house stays.

Pair with a pelmet.

Without a pelmet, cold air between the window and curtain will sink down (because it’s denser and heavier). This will draw in warm air at the top of the window, which cools against the glass and sinks down, continuing the vicious (and chilly) cycle (see illustration). Pelmets help stop the cycle, so they make your curtains insulate more effectively. If you don’t have pelmets consider getting some added, or for a cheap temporary option, place a rolled up towel or length of thick cardboard across the top of your curtains.

Shade your windows in summer.

The windows on the north and west sides of your apartment will cause heat gain in summer. There are a number of simple DIY foil products that can be applied from the inside, to reflect the light off a window that might be too difficult to shade from the outside. This is also a good option for renters. You may need to double check with your owners corporation or landlord if the reflective film can be seen from the outside.

Double glaze.

There are several options for double-glazing, from simple DIY solutions to replacing windows. See below for some double glazing options:

  • Do-it-yourself plastic film

To retrofit existing windows, plastic film is an affordable do-it-yourself option, which gives the double glazed effect. It’s available in hardware stores; and some brands such as Clear Comfort are also available online. Our video shows how easy it is to install the double-glazing film.

  • Add-on panes

Another option is additional acrylic window panes with frames that attach to your existing ones. One product that works this way is Magnetite. Magnetite has been designed to work with your existing windows, doors, skylights and glass areas. A small frame fits around the inside perimeter of the area and the Magnetite panels attach magnetically to the frame.

If you do consider replacing windows and balcony doors with double or triple glazed windows and doors, ensure they have appropriate insulation and glazing. Even though, it may cost more upfront, you’re likely to save money in the long run.

Consult The Windows Energy Rating Scheme (WERS) to help you choose the most efficient windows.

Make sure to consult your climatic zone to choose the appropriate window type. Here are the recommendations for those living in Sydney.