double glazing worth the money in australia

Windows are the weakest part of the building envelope, so improving them helps. The question is not whether it works, it is whether the same money spent elsewhere would do more, and in most Australian homes the answer is that it would.

Usually higher return, and cheaper

• Ceiling insulation, if it is missing, thin or compressed. This is almost always the best value upgrade available.
• Draught sealing around doors, windows, exhaust fans and downlights, which is inexpensive and often dramatic.
• External shading on the windows that get summer sun, since stopping heat before it reaches the glass beats any glazing.
• Heavy, well-fitted curtains with pelmets, which reduce winter heat loss through existing windows substantially.

Where double glazing genuinely comes first

• Cold climates, where the heating season is long and the temperature difference across the glass is large.
• Noise. This is often the real motivation, and laminated or acoustic glazing is the only thing that addresses it.
• New builds and major renovations, where the marginal cost over single glazing is much smaller than a retrofit.
• Rooms with very large glazed areas that are uncomfortable to sit near regardless of the heating.

Worth knowing: the frame matters as much as the glass. Double glazing in an aluminium frame without a thermal break conducts a great deal of heat around the improvement you just paid for.