Retrofit double glazing
Retrofit double glazing swaps the single glass in your existing windows and doors for double glazed units. The frames stay where they are, and you get a sealed layer of air between two panes of glass.
A common sign
“The frames are fine. It’s the glass that’s freezing.”
About retrofit double glazing
Double glazing, without new windows.
A double glazed unit is two panes of glass sealed together with a gap between them. In a retrofit, the installer takes out the old single pane and fits a double glazed unit into the frame you already have, adapting the frame where needed so it sits properly.
It suits homes where the frames are still in good condition, including aluminium and timber windows you’d rather keep. Because the frames stay, there’s usually less building work than replacing the whole window.
Helps with
Cold rooms with sound frames
Helps with
Windows you want to keep
Helps with
Condensation on single glass
Ask this
Ask whether your frames can take a double glazed unit. Some older or very thin frames need adapting first, and some are better replaced.
Not sure where to start?
Stop guessing, start saving: find your home’s energy score.
Don’t waste money on upgrades you don’t need. A professional home energy assessment shows where your house loses heat and power, so your budget goes where it makes the biggest difference.
Find an assessor near meRetrofit double glazing installers
Find retrofit double glazing installers near you.
A few of the 54 listed across Australia
Thermawood Retrofit Double Glazing
5.0 538 Google reviews
Draught and weather sealingRetrofit double glazing
Based in Thornbury
Original Glazing
5.0 91 Google reviews
Double glazed aluminium windowsWindow and door replacementRetrofit double glazing
Serves Balwyn and Deepdene and nearby suburbs | Based in Balwyn
Just Rite
4.3 259 Google reviews
Ceiling and roof insulationWall insulationUnderfloor insulationDraught and weather sealinguPVC double glazed windowsWindow and door replacementCeiling insulation top upRetrofit double glazing
Based in Hume
Ecocraft Pty Ltd
5.0 11 Google reviews
Window and door replacementuPVC double glazed windowsDraught and weather sealingCeiling and roof insulationUnderfloor insulationWall insulationHome energy assessments and auditsHeat recovery ventilationRetrofit double glazing
Based in Hurstbridge
More in windows and glazing
Other upgrades in this category.
Single glazing is where a great deal of your heating escapes. These trades retrofit the windows you already have, or replace them properly.
uPVC double glazed windows
The warmest frame of the common options, and the quietest. A full replacement rather than a retrofit.
Double glazed aluminium windows
Slim frames with a thermal break. Common where the look of the original windows has to be kept.
Triple glazed windows
Three panes for the coldest rooms and the noisiest roads. Rare in Australia and worth asking who has actually fitted it.
Secondary glazing
A second pane fitted inside the window you already have. Far cheaper than replacement, and it works on heritage frames.
Window and door replacement
Not every glazing job is double glazing. Rotten frames, jammed sashes and doors that never sealed properly.
Before you choose an installer
See our guides on windows and glazing.
Related goal
Comparing window upgrades?
See every way to improve your windows, from new glass in your old frames to full replacement.