Windows

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; 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. Here’s a link to a facebook post we did about them.
  • Double glaze. There are several options for double-glazing, from simple DIY solutions to replacing windows. See below for some double glazing options.
  • Insulate skylights. Skylights can cause substantial heat loss during winter. A cheap DIY option is to attach bubble wrap to the inside of the light. Installing double glazing, or fitting a ceiling diffuser, offer more permanent solutions
  • Shade your windows in summer. The windows on the north and west sides of your home will cause heat gain in summer. The heat comes from sunlight hitting the window, so if you can shade the window from the outside you can keep the house much cooler. External blinds or deciduous plants are good, so that you can still let the light in during winter, when you need it. There are also 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.

For personalised advice on how best to improve the efficiency of your windows and the comfort levels in your homeĀ sign up on line and select draught proofing to hear directly from our carefully selected supplier.

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 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.

Replacement windows

For a more permanent option consider double or triple glazing, especially if you’re building or renovating. But first watch this Moreland Energy Foundation video, which explains exactly what double-glazing can and can’t do. And if you are replacing windows, it’s worth noting that the material that a window frame is made from can also affect how well the window insulates. In general, PVC and timber frames perform better than metal frames.