How Long Are Double-glazed Windows Guaranteed for? Why Use Them, Warranty, Standards, and More!

If you occupy a residential or commercial space in Perth, insulation is probably on your radar for its benefits where comfort and energy saving are concerned. Whether it’s uPVC double-glazed windows or other insulative elements, people seek them out for good reason.

You’ve probably heard of a double-glazed door or window before, and one of the biggest questions that tend to crop up surrounds longevity. If you were to have double-glazed windows, how long would they be guaranteed for?

After all, structural investments such as these are meant to be long-form. No one wants to be having a new set of uPVC windows or sliding double-glazed doors set up every few years.

You’ve come to the right place to get your answer. Below is a look at why double glazing is desirable, as well as the life expectancy of the technique, alongside other useful information.

Why Double Glazing Is Offered in Australia

The idea of an insulated glass unit doesn’t in the world of construction unless tweaks are made. Without considering double glazing, glass conducts heat very well. While this makes clear or tinted glass appropriate for many applications, the home, for example, is not one of them because of the insulative capabilities needed.

Worse even, noise levels and high winds will become a nuisance if one pane of glass is the only line of defence. Look at standard aluminum windows, for example. There’s not much protection there.

However, the act of double glazing uses a second pane of glass to support the first. The total measure of the glass thickness is not necessarily the most important measure. Instead, it’s the air layer that becomes trapped between the two panes.

Since air is terrible at heat conduction, the double glazing translates to a true insulated glass unit.

Of course, beyond the changes in energy efficiency, your uPVC double-glazed windows, alongside other variations, will provide better water tightness, higher levels of wind resistance, some level of noise cancellation, and more!

What Kind of Warranty Should You Expect on Your Double-glazed Window?

Moisture is a big part of the problem. However, it’s compounded by the lack of proper double glazing technique that was indicated above.

Looking back at the wooden windows, everyone knows water will cause them to rot. Beyond that though, the double glazing itself will fail in the presence of excessive moisture.

The technique that causes the problem is the use of a square rebate to house the insulated glass unit, after which a silicone sealant is used.

Initially, your double-glazed windows look great, and you will assume that the seal is tight. There are two problems here, however.

First, a square rebate is highly susceptible to water getting trapped in it. The presence of vapour will drain the seal of contaminants, which results in a progressive deterioration process.

A damaged seal means failed double glazing. At that point, you don’t have a tight air pocket in a sealed assembly. Instead, moisture and external air are trapped easily, resulting in the misty aesthetic you may sometimes notice on double-glazed windows.

No repairs can be effected to address this. Only a replacement will do.

For clarification, the problem is not the entry of the water. That’s unavoidable with double glazing. However, any water that gets in needs to have a way to get out.

Can Anything Be Done to Increase How Long Double Glazing Will Last?

As you would probably imagine based on all that has been said so far, altering the technique would be a good place to start in ensuring that there’s greater longevity built into the configuration.

One alternative approach is the use of a sloped area underneath the glass unit instead of opting for a square rebate.

This is then combined with a drainage system allowing for the moisture to drain after it has been caught in the assembly.

Additionally, a dry glazing system can be used that takes advantage of silicone blocks. Going this route avoids the traditional silicone sealing method which has a reactive relationship with the moisture.

The polysulphide seal must remain intact, and this configuration will offer the support to ensure that the double glazing assembly will hold.

What Kinds of Standards Are There for Double-glazed Doors and Windows?


A warranty for double glazing products will typically be established based on the meeting of industry standards. In Australia, some of these standards are:

  • AS 153o Methods for Fire Tests on Building Materials

  • AS 2047 Windows in Buildings

  • AS 4055 Wind Loads for Housing

  • AS/NZS 1170 Structural Design Actions

  • AS 4420 Windows

What Types of Windows and Doors Is Double Glazing Featured in?


Double glazing is featured in various configurations, including casement windows, sliding double-glazed doors, and more! Here’s a quick look at some of the prominent ones

Stacker Doors

If security is on your radar, then an Aluplast uPVC double-glazed stacker door is a great investment. It boasts steel reinforcement, multiple security locking points, and barely requires any maintenance. Put simply, it allows you to bring the outside in and the inside out.

Two different configurations are available here. You can have a three-pane stacking to one side or six panes with two stacking on either side.

Sliding Doors

Double-glazed sliding doors are most certainly a great way to refine any space. For example, your home in Perth may be able to benefit aesthetically and functionally from the implementation of sliding glass patio doors.

Yet again, Aluplast is the way to go here, as the uPVC doors are a great way to introduce space to the room. Bifold doors, for example, do not have this advantage.

There are three different configuration options available. The first is two panes with one sliding. Next, there are three panes with one sliding and finally, four panes with the middle two sliding.

Lift and Slide Doors

Not to be confused with double-glazed tilt and slide doors, these designs are incredibly stylish and will most certainly add to any property’s value in Australia. The lift and slide door is very stylishly built and is great for wide areas, considering they can span a distance beyond 6 meters with only two glass panes.

Those wishing to enhance inside and outside living in Western Australia will benefit greatly from these double-glazed designs.

Tilt and Turn Windows

Whether a design consists of double-glazed fixed panels or their movable counterparts, careful consideration must be given to their implementation in contemporary housing. Thankfully, there isn’t a need for a second thought with Aluplast tilt and turn windows.

Not only do they look great, but they bring all the benefits of double glazing indicated above, including energy efficiency and noise reduction. Additionally, they happened to be incredibly low maintenance and the security is also high calibre.

You get a couple of options here where the opening is concerned. On the one hand, the windows can open fully inwards. On the other hand, they can simply tilt inwards. If you ever needed a convenient fire exit window, this is a great design.

Finally, you can set these up virtually anywhere you were considering putting windows, especially considering the sizing options available.

Sliding and Stacking Windows

One of the most versatile double glazing options comes in the form of sliding and stacking windows. Sometimes, limited space means having to reconsider what would otherwise be great window configurations.

However, these windows are perfect in spaces where there may be a limited area to work with. The uPVC double-glazed sliding style window frame has an incredibly refined look and thanks to the removable and highly discreet fly system, basking in it will be no issue.

Depending on your current or intended visual, there are a host of colour options that you can choose from. How does a realistic wood grain sound, for example?

Note that both fire and weather resistance are baked into Aluplast uPVC double glazing, and they’re also usable in just about any property type.

Awning Windows

Just as the name “tilt and turn double glazed door” would clue you into the way the door operates, double-glazed awning windows open outward while hiding at the top. Therefore, you get a weather shield based on position alone, allowing for you to enjoy non-weather restricted ventilation around the clock.

Many Australian households go for the durability that Aluplast uPVC window frames offer, especially since they provide greater visibility and natural light around the home.

Remember to consider which awning window will visually fit your property the best as you make your selection.

The Bottom Line


Double glazing, when done well, can make all the difference in longevity and can be guaranteed for at least 10 years. The technique used by installers is very important. Arguably more critical though, is the set of products used. If you want to ensure you’re getting the best in Perth, look no further than Thermaglaze Double Glazing.

Not only do we supply some of the most highly rated double-glazed windows and doors available, but we also do expert installations to ensure the configurations stick around for as long as they are expected to. Call 1300 022 867 to find out more or book a free measure and quote here!

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