How much do double-glazed windows cost? [Australia 2024]

When building or renovating your home, it can seem like there are endless options in terms of construction materials, features, components and inclusions. Having those options means you can really make your home unique, but they can also come with an additional cost. For most people, budget is among the most significant considerations when it comes to construction or renovation. 

 

Windows are a significant consideration when it comes to the energy efficiency of your home, as they can be a source of heat gain or loss. As the cost of living increases, and with up to 40% of heat energy lost through your windows, improving their efficiency can reduce energy costs.

 

What are double-glazed windows?

double-glazed panes of glass are manufactured using two single panes of glass separated by an air gap (usually around 10mm). The gap is sealed, and acts as a break between the inside and outside panes of glass. The air gap is filled with gas which further increases the insulation effect of the glass. double-glazed windows are very efficient, reducing your heat loss or gain by up to 30% compared to regular windows.

 

double-glazing is a lot like insulated clothing or housing insulation (pink batts). Glass conducts heat very effectively, but the gas trapped between two layers of glass is a lot less effective at transferring heat. That means double-glazed glass is a better insulator than a single pane of glass. 

 

If you have single-glazed windows and you’re not undertaking significant renovations, retrofitting double-glazed windows is absolutely an option. Sometimes this can take the form of a second pane of glass attached to your existing glass. While this isn’t quite as effective as actual double-glazing in terms of temperature retention, it can be a much more affordable option. 

 

What is the average cost of double-glazed windows?

The average cost for double-glazed windows is around $700 per square metre. Of course, prices will be higher or lower depending on your location, installation costs, and the number of windows you are having installed at once. 

 

Glaziers our experts spoke to while researching this post have suggested significant variation in the price of double-glazing per square metre. Simple windows with aluminium frames can start at $300 per square metre, but prices can go as high as $1,200 per square metre for windows with wooden frames that need to be recrafted from scratch or significantly altered. 

 

What factors can affect the price of double-glazing?

As outlined, costs depend on your location, installation costs, and the number of windows you are having installed at once.

 

Location has an impact on the number of tradies available in your area that install double-glazed windows. As installing double-glazing isn’t a safe DIY task, you’ll need the help of a professional and so where you live will make a difference to the availability of qualified professionals. It will also make a difference in terms of the average cost per hour for tradie labour. Thankfully, material costs don’t vary significantly between states, so those should be fairly consistent. 

 

Installation costs include labour, as discussed above, and the cost of having to vacate a home you’re living in while your windows are removed and replaced. It’s an important consideration, as is the security of any property left inside your house while the process is underway. Talk to your installers to see what you can do to manage these costs. 

 

Of course, one of the most significant considerations is the number of double-glazed windows you plan to install, or the number of regular windows you plan to have replaced with double-glazed windows. Increasing the number of windows you want double-glazed means increasing the amount of work that needs to be done to refit windows, repair plaster in any surrounding walls, and apply water-proofing membranes and sealant. 

 

How much does it cost to double glaze the windows of a 3 bed house in Australia?

As outlined, tradies estimate that glazed windows cost between $300 to $1200 per square metre, which translates to an average of around $700 per square metre or around $1000 per window. This obviously varies significantly depending on circumstances and other costs. 

 

On the basis of a cost of around $1000 per window, you can expect to pay between $8,000 and $15,000 for an average 3 bedroom house in most states of Australia. As discussed earlier, you may be looking at the lower end of this range if you choose to install double-glazed windows when you first build your house rather than when you’re renovating. 

 

Is double-glazing worth the cost?

The simple answer is, “it depends where you live”. In states like Tasmania where colder weather is more common, double-glazed windows can allow for the more effective heating of your house, saving you money and reducing your environmental footprint. When it comes to saving money, you’ll likely see financial benefits more quickly than if you were located in northern New South Wales or Queensland. 

 

That said, double-glazing can make cooling your house more efficient too, as it simply limits heat transference. That means cooling your house in warmer areas can be made more efficient. But there is a reason why double-glazing is far more common in Europe and the United States where cold weather makes centralised heating essential and it’s absolutely a necessity in cold climates. 

 

However, it’s also true that installing double-glazing during construction is far cheaper than renovating by removing existing glass and replacing it with double-glazed glass, which often necessitates replacement of the windows themselves. If your preference is for double-glazing and you have an opportunity to have double-glazed windows installed as part of a new house build, you should absolutely consider it. You achieve considerable savings when compared to making that change down the track.

 

How many years do double-glazed windows last?

Though modern glazing techniques mean the lifespan of all windows is still increasing steadily, double-glazed windows should last at least 20 years under most circumstances. Given the general lack of extreme hot or cold weather in Australia, double-glazed windows should last between 25 to 35 years in Australia.

 

Of course, Australia has other extreme weather including flooding and storms, both of which are a risk to any type of window. We’re big fans of home and contents insurance here at BorisDoes and so the assumption is that most people will invest in insurance most of the time. 

 

What are the benefits of double-glazed windows?

There are a range of benefits to installing double-glazed windows, either when you’re building or renovating or just as an add-on to your existing windows. Energy efficiency is a significant factor, and probably the highest consideration for most people. You can effectively reduce air-conditioner use by up to 30% each year in some cases, representing a significant savings on an annual basis.

 

Other benefits include:

 

• Sustainable and environmentally friendly - double-glazing is a way to improve the insulation of your house, resulting in a need for less environmentally friendly fibreglass or other insulation batts. 

 

• Durable with low maintenance - though glass does break, as an insulating option, double-glazed windows are durable and should have good longevity, meaning you’ll get the benefit of your investment for many years. 

 

• Increases the value of your house - any capital investment that improves energy efficiency and reduces future power bills will increase the value of your home relative to other homes that haven’t had the same investment. 

 

• Less condensation - condensation is a common issue in most homes and occurs when moist air meets cooler objects. The two window surfaces are each closer to the adjacent temperatures, reducing build-up of condensation and mould.

 

• Noise control - double-glazed windows reduce mid-to-high range frequencies, such as human voices and dogs barking. Thicker double-glazed glass with a large gap between panes (100mm) reduces low frequencies, including plane and traffic noise. 

 

• Reduces fading - furniture and wall-hangings can fade over time because of exposure to UV rays and heat from the sun. Double-glazing reduces this effect and windows that include UV protective film are even more effective. 

 

What are the disadvantages of double-glazed windows?

We’ve talked about the advantages of double-glazing but what are some of the disadvantages? Are there any disadvantages at all? The simple answer is “not many”, but let’s expand on that. 

 

While double-glazing can be expensive, it’s certainly not the most expensive energy efficiency improvement option. In fact, it can be among the cheapest if you’re building your home or undertaking extensive renovations, as we have explained. 

 

However, in the same way double-glazing traps heat and reduces heating costs during colder months, it can do the same during warmer months. Given Australia has higher average temperatures than those countries where double-glazing is most popular, this likely comes as no  surprise. It does mean, though, that you may need to take extra steps to cool your house during warmer weather, though this will likely involve opening windows to let trapped warmer air out, and then cooling your house with air conditioning as normal. 

 

Once your house is cool, your double-glazing should help to keep it cool, further saving on energy costs. While this might be considered an inconvenience for some, many won’t consider it a significant issue in light of the potential savings and energy efficiency gains. 

 

Conclusion

Double-glazing remains a less common option for Australian home builders and renovators, and an even less common option for home-owners as a standalone installation. The reality is that Australia doesn’t have the icy-cold weather of Northern Hemisphere countries where double-glazed windows have been popular for decades.

 

But in areas where average temperatures are lower and ice and snow are more regular occurrences, double-glazing can be a great, cost-effective insulator. You can always talk to your BorisDoes tradie about the best options for you and the most effective ways of installing double-glazed windows in your home.

 

However, the benefits of double-glazing extend beyond just thermal insulation. In Australia, where the sun can be particularly harsh, double-glazed windows offer significant advantages in terms of reducing heat gain during the summer months. This can lead to a substantial reduction in air conditioning costs, making double-glazing an attractive investment even in warmer climates. Additionally, they provide excellent sound insulation, which can be a blessing in urban areas where noise pollution is a common issue.

 

Moreover, double-glazed windows can increase the overall value of your home. Potential buyers often look for homes that are energy-efficient and offer high levels of comfort, making properties with double-glazed windows more appealing in the real estate market. This is an important consideration for homeowners thinking about future resale value.

 

For those concerned about the environment, double-glazing is an effective way to reduce your carbon footprint. By lowering the need for heating and cooling, these windows decrease overall energy consumption, aligning with a more sustainable lifestyle.

 

As the awareness of double-glazing's diverse benefits grows, more Australians are considering them as a viable option for their homes. Whether you're building anew, renovating, or simply looking to improve your home's efficiency, discussing double-glazing with a knowledgeable tradie from BorisDoes can set you on the right path. Remember, the initial investment might seem significant, but the long-term savings and comfort can truly make it worthwhile.