How much does it cost to double-glaze windows?

SEAN CALLERY
Deputy Editor · 27 August 2021

An ongoing financial dilemma for many homeowners is the cost versus benefit equation of certain improvements and additions around the house. Will you be adding value? Will possible long-term savings eventually outstrip upfront costs? Whether or not to install double-glazed windows is one example.

If you’re looking to make your home more energy-efficient, block out some external noise and potentially make your property more secure, double-glazing your windows and doors could be an option worth considering. But will your eyes glaze over when you hear the cost? Let’s find out.

What are double-glazed windows?

Double-glazed windows differ from traditional, single-glazed windows by using two separate pieces of glass separated by an airtight space that acts as a form of insulation. According to specialist provider, Next Generation Glass and Double Glazing, double-glazing utilises two separate pieces of glass, separated by a vacuum. The vacuum layer acts as an insulative barrier. The glass used can be laminated or UV-tinted, but is otherwise similar to the glass used in single-glazed windows. There is also such a thing as triple-glazed windows, but they are more commonly used in colder parts of the world, such as Europe.

Generally speaking, double-glazed windows can be added to a property in one of two ways:

  • Custom-made double-glazed windows: these are produced and installed as a single unit made up of two panes of glass. This approach is commonly used on the windows and doors of new houses and extensions, where the building work is being done from scratch.
  • Retrofit double glazing or secondary glazing: this is where an additional pane of glass is added to an existing single-glazed window on a property. This is referred to by some in the industry as ‘Frankenstein glazing’ and is sometimes used when an existing home is being renovated.

How much do double-glazed windows cost?

Double-glazed windows and doors are most commonly priced by the square metre. According to ServiceSeeking.com.au, the average cost of newly-fitted double-glazed windows in Australia is around $1,350 per square metre. In some cases, the cost can also be quoted on a ‘per opening’ basis, with the total cost determined by how many windows and doors are being fitted.

ServiceSeeking estimates that retrofitting – adding double-glazing to windows or doors after they’ve been built – is approximately 10% to 20% more expensive than custom-made double glazing.
If you only need the glass installed, and not the frames, hipages.com.au says you can expect to pay upwards of $200 per square metre for double-glazed glass and $220 per square metre for a low-emission option. On top of that, you would likely need to separately factor in the cost of the glazier, which could be between $70 and $90 per hour. If you need emergency repairs carried out, this could cost up to $150 per hour.

While these average costs might give you a general idea of how much you may need to spend, the exact cost of double-glazing can depend on a wide range of variable factors, making specific prices for your situation difficult to arrive at without having an installer visit your property.

Some of the key factors that can determine price:

• The type and specifications (thickness, tinting etc.) of the glass.
• The material used for the window frame – expect to pay up to $1,500 per square metre (materials plus installation) for top quality timber-framed double-glazed windows. Aluminium double-glazed windows will likely cost less.
• The size of the window or windows you want to double-glaze
• The style of the window – WA-based firm Climateframe Double Glazing says awning windows are cheaper than sliding windows, as they cost less in materials and labour to manufacture.
• The hardware the window requires – a fixed window is usually the cheapest option as it doesn’t require handles or similar mechanisms. As a general rule, the more components a window has, the more expensive it will be.

→ Renovating a home could change what insurance cover you may need: Compare home and contents insurance providers.

What are the options to pay for double-glazed windows?

How you fund the work may depend on how much it costs. There are several options available for would-be home renovators to consider, including:

Savings: If you have enough money in savings, this is generally the cheapest and most straightforward way to pay for work around the house, as you will avoid interest costs and needing to apply for finance/

Home loan: If this job is big enough, or you are doing a range of jobs at the same time, one choice you may consider is or restructuring your home loan, or adding a to it. If you’re ahead with your home loan repayments you may be able to access funds though your loan’s , which could help reduce the interest paid on your loan while still allowing access to your money (although it’s wise to keep in mind there could be some fees involved here, too, and higher interest rates could apply to these types of loans).

If you’re building a new home or planning a major renovation, like a second-storey extension, a could be ideal, or at least an option to consider. A construction loan is a type of home loan where the funds are drawn down in line with various stages of the project. So you’re not paying interest on the full loan balance until the project is complete, which can be a valuable money saver.

Personal loan: Depending on your personal circumstances and the cost of the job, you may consider using a personal loan to fund the work. This could be a secured loan, or an unsecured loan. It’s worth keeping in mind, though, that interest rates are generally higher for personal loans than for home loans, and it’s a good idea to read the lender’s terms and conditions first. You can compare personal loans with Canstar.

Green loan: A green loan is a personal loan used to fund home improvements that will make your home more energy-efficient – thereby saving you money in the long run, while also reducing your eco-footprint. Not all banks offer green loans, and those that do typically specify exactly what projects qualify for a green loan. Some lenders include double-glazing on their list of approved projects, as they are often considered an eco-friendly addition to a home. A recent analysis of the products on Canstar’s database found that green loans can come with interest rates well below the rates offered on regular personal loans.

Credit card: It may also be possible, depending on the cost and your ability to repay the debt quickly, to pay for the job on a credit card. There could be some fringe benefits for doing so, such as extra insurance cover in some cases (read the Product Disclosure Statement for the card’s insurance policy to find out the conditions of the cover). Keep in mind that credit card interest rates are typically much higher than home or personal loans, and interest can quickly accumulate on large balances, so it is a good idea to weigh up your options and consider them carefully. If you don’t think you’ll be able to pay off the card’s balance in full each month, it may be worth seriously re-considering whether a credit card is the right option for you.

If you’re currently comparing credit cards, the comparison table below displays some of the low interest credit cards currently available on Canstar’s database for Australians looking to spend around $2,000 per month. Please note that this table features links direct to the provider’s website, and is sorted by Star Rating (highest to lowest), followed by provider name (alphabetical). Use Canstar’s credit card comparison selector to view a wider range of credit cards.

How to save on the cost of double-glazed windows?

While it’s unlikely to be a cheap undertaking one way or another, you may be able to save some money on the cost of adding double-glazed windows by making some savvy choices along the way.

Think carefully about colours and window style, which can add to the cost. Choosing simple openings, aluminium (rather than timber) frames and selecting awning or casement windows are all potential ways to save.

According to ServiceSeeking.com.au, you may be able to reduce the cost of adding double-glazed windows to your home by doing some of the work yourself, such as by measuring, ordering and purchasing the materials for the window and then simply paying for someone to fit them.

But even this preliminary work is likely to require a degree of knowledge and skill. So before you jump in yourself, it could be worth thinking carefully about the risks of doing so, for example by getting the measurements wrong or buying the wrong type of window.

Looking at other saving options, the Australian Government’s Department of Energy suggests cheaper options to double glazing, including products with a thin plastic coating that fit over windows.

And of course, regardless of which insulation technique you choose, there’s the age-old method of getting bang for your buck simply by shopping around for the best-value supplier. If you get a number of quotes from different companies, you might be surprised at how their prices vary. Just make sure you’re comparing apples with apples, i.e. the same kinds of glass, frames and so on.

Importantly, Australia’s climate is very different to Europe’s when it comes to UV rays and the heat. So your double-glazed windows need to be tested to Australian standards. Be sure to ask your provider about this.

What are the benefits of double-glazed windows?

Some of the potential benefits of adding double-glazed windows to your property, as outlined by window supplier Ecovue, can include:

  • Energy efficiency: The sealed air between the panes of glass act as a form of thermal insulation. This is designed to lock in the cool air in your house in summer and stop heat escaping in winter. It could mean you’ll be using your heater and air conditioner less, with a reduced power bill as a result. In fact, Ecovue estimates two
  • Noise reduction: As well as keeping cold or hot air out of your home, double-glazed windows can also help to shut out more external noise than their single-glazed equivalents. This could mean a better night’s sleep, a home office where you’re able to concentrate better, or reduced exterior noise from, say, a neighbour’s barking dog or overhead aircraft.
  • Safety and security: According to Ecovue, double-glazed windows are harder to break than normal windows. They may be particularly effective if coupled with for your windows and doors.
  • Bushfire protection: Ecovue says double glazed windows and doors are recognised as one of the measures you can take to protect your home against bushfires. This could make it worth mentioning double-glazing to your insurer when you take out . If you live in a bushfire-prone area then depending on your insurer, it could see you save on premiums.
  • An uptick in your home’s value: A 2020 study by the University of Wollongong found energy-efficient homes fetch higher prices than less energy-efficient properties of comparable value. In fact, the price premium of a higher energy rating can be 5%-10%. So, the cost of double-glazing could well be compensated for by an uptick in your home’s market value.

What are the disadvantages of double-glazed windows?

Some of the potential drawbacks of installing double-glazed windows could include:

  • The upfront cost: While they could potentially deliver energy savings in the long run, double-glazed windows do cost more than single-glazed windows. According to Hipages, it may take five years or more to recoup the extra cost of double-glazed windows through energy savings. You would also have to consider the potentially higher costs involved if your double-glazed windows need to be replaced in the future. Also weigh up how the installation would impact on other features of your windows, such as blinds or shutters that are already installed.
  • Style fit: It may not always be easy to find double-glazed windows that fit with the style of certain properties, particularly older ones, as double-glazing tends to be a more modern style of window. However, retrofitting your existing windows may be an option that would mean certain elements of your existing window frames remaining in place and retaining their original style.
  • The added weight: If you’re installing double-glazed windows on an existing property, particularly an older building, talk to your supplier about the increased weight of the extra pane of glass. It could possibly cause materials around the window to warp out of shape over time. This can potentially in turn allow draughts of air in and cancel out any increased insulation that the window itself might provide.

Can double glazing save you money on energy bills?

One of the main potential benefits typically associated with double-glazing is the impact it can have on your home’s energy efficiency, and the potential knock-on effect on the amount you spend on your energy bills.

A single pane of glass is not generally a good insulator. Add a second pane though, and the difference can be significant. According to Energy.gov.au, heat gain and heat loss through windows is responsible for 25%-30% of residential heating and cooling energy use. But Sustainability Victoria says double-glazed windows are very energy-efficient, as they can reduce heat loss or heat gain by almost 30% in comparison to single-glazed aluminium windows. Add in home insulation, and it’s possible to reduce the cost of heating and cooling a home by around 40% to 50%.Put another way, DoubleGlazed.com, an Australian manufacturer of windows and doors, estimates that double-glazed windows have the potential to cut your electricity bill by 25%.

However, any actual savings specific to your household would depend on factors such as the size of your home, the quality of the double-glazing and the climate where you live, and of course how much your annual energy bill is to start off with.

Image Source: Tarapong Srichaiyos (Shutterstock)


Thanks for visiting Canstar, Australia’s biggest financial comparison site*