Window insulation
On this page
Windows can be responsible for up to one third (31%) of heat loss in an uninsulated house.
Take action
Hang curtains and blinds
Good, thermal backed and lined curtains can cut heat loss through windows by up to a quarter (25%). [1.]
Curtains should be bigger than the window frame and close fitting with no gaps for warm air to escape. They should either be ceiling to floor, or have a pelmet to stop cold air dropping out from below the curtains. Use thermal or close-woven materials and linings.
Draught proof your windows
Draughts and air leakage can increase your heating costs by more than 20% and make your home uncomfortable. Use the tips on draught proofing in the section on Air leakage and draughts.
Installing new windows
If you plan to install new windows, read the discussion and follow the tips on window size and placement in the section Your building design: Windows.
Double glazing
Find out more about the benefits of double glazing in the section on Insulation for new homes.
Insulation for new homes
To find out more about double glazing options for new and existing windows go to the websites listed below under More information.
More information
Insulation
- For comprehensive information download the Department of Building and Housing booklet Your guide to smarter insulation, PDF 2.9 MB [Smarter Homes insulation booklet. ]
Glazing
- Glazing and glazing options [Smarter Homes website.]
- Checklist for regular maintenance of Windows and doors [Consumer Build website.]
- Window Energy Rating Scheme (WERS) [NZ Window Association.]
Note:
[1.] NZEECS, 2007, page 22.