The cost of Double glazed windows. Everything you need to know.




Are you considering double glazed windows for your Sydney property and wondering how much they cost?

Let’s unpack your pricing considerations and the things to ask a glazing professional.

There’s a lot of helpful information packed into four easy-to-read sections, but you can also scroll to the end for our contact details if you need a price for double-glazed windows double-quick.


DID YOU KNOW? Double glazed windows are recommended by the Australian Energy Foundation (government organisation) as a way to improve the energy efficiency and acoustics of your home.


  1. Double glazed windows unpacked

Double glazing (also known as insulating glass) is basically two window panes in the same frame, with a sealed gap between each pane. The gap contains a filler which can simply be air, but in many cases a pressurised gas (usually argon) is used to seal the panes and improve the insulation ability of the windows. We’ll talk more about fillers in the Section 3: Cost Considerations.


It bears repeating that true double glazing requires two separate panes of glass that are contained in a single window frame. Double glazed windows are NOT:


  • Laminated windows — this is where two pieces of glass are permanently bonded together and sit in the window frame as a single piece of glass. Laminated windows don’t provide reliable insulation.
  • Storm windows/sashing — these are glass or acrylic add-ons to an existing window. Storm windows often create condensation problems in the home and don’t offer the same level insulation as double glazed windows.


  1. Benefits of double-glazed windows

Now you’re clear on exactly what double glazed windows are, let’s take a look at some of their key benefits. Keep these in mind when budgeting for the cost of your new windows, because even though they are generally more expensive to install, double glazed windows will save you money over the long term.

(A) Insulation

“Energy efficient windows make your home more comfortable, dramatically reduce your energy costs and help to create a brighter, cleaner and healthier environment.”


Australian Energy Foundation


Did you know that your windows have a huge impact on the heating and cooling loads of your home? The Australian Energy Foundation state that around 40% of heating energy is lost through your windows, and a massive 87% of the building’s heat enters via windows.


Energy efficiency is one of the primary benefits of double glazed windows as the spaced between the two pieces of glass acts as an insulating barrier between the interior of the home and the weather outside. Installed correctly (by reliable professionals), you can quickly reduce your electricity bill in both summer and winter.


  • Heating benefits — in winter double glazing reduces heat loss from the interior of your home. Warm air stays inside, and cold air stays outside.
  • Cooling benefits — double glazed windows are extremely efficient at keeping hot air outside.

(B) Condensation

At the same time your double glazed windows are insulating your home from the often harsh Sydney climate, they also reduce condensation. Condensation reduces window visibility, looks ugly, and can also lead to a build-up of mould and damp.

(C) Acoustics


“Sealed double glazing reduces transmission of medium to high frequency noises such as the human voice. To reduce low frequency noise such as traffic and aircraft, choose thicker glass, preferably double glazed.”


Australian Energy Foundation


Double glazed windows are recommended by the Australian Energy Foundation for reducing noise in your home. Depending on the size and placement of you windows you can minimise external noise created by:


  • Human voices — reduce the sounds of cranky neighbours, excited school children, and animated passers-by.
  • Vehicles — minimise noise made by the cars, trucks, motorbikes, planes, trains, boats, and drones that pass by your home.
  • Animals — get rid of the sound of barking dogs and fighting cats.
  • Music — parties are fun if you’re there, not so much when they’re louder than the TV or penetrate your sleep earplugs. Double glazed windows will certainly reduce this type of neighbour noise.


Acoustic performance also includes the noise that you make too. If you want to max out your home stereo system or practice guitar late at night, double glazed windows will also help prevent these sounds from annoying the neighbours.


(D) Security

Apart from the improvements to the insulation, condensation, and acoustics, double-glazed windows also greatly improve security in, and around your home. It’s more difficult to break through multiple layers of glass, and the frames aren’t easy to remove because they are completely sealed.

(E) Property Value

Finally, consider the additional value that double glazed windows will add to your home. With the improvements to the lifespan of your windows and reduction in insurance premiums — studies and experts report as much as 10%.


DID YOU KNOW? Double glazed windows can also reduce home and building insurance premiums.


  1. Cost considerations

There are many factors that can impact the price of your double glazed windows. Make sure the glazing company takes the time to explain and itemise the cost of each of the following:

(A) Surface Area

It goes without saying that the larger the glassed area, the more expensive the price. Any reputable glazier will advise you on safe and sustainable window-to-floor ratios.

(B) Glass

Your next pricing consideration is the thickness, U-value and quality of the glass itself. Thicker glass delivers greater insulation, noise reduction and security, but it’s also more expensive. The minimum thickness of the windows will depend on the wind load requirements of the building.


DID YOU KNOW? the U-value of the glass (lower values are best) indicates how fast hot air (not sunlight) will pass through the glass. The U-value can also impact the price of your double glazed windows.


(C) Frames

Your window frame pays a huge role in insulation and noise reduction, so find out upfront what your glazier intends to use. Here’s a quick overview of the 3 most common:


  • Aluminium – aluminium window frames are the most popular frames in Australia, but the trouble with aluminium is it easily absorbs heat and cold. In summer your frames will quickly absorb the burning Sydney sun, while in winter they’ll soak up the cold wind blowing off the Harbour (or coming down from the mountains).


         At the same time aluminium frames are not 100% airtight and are susceptible to rust and             corrosion — a huge issue if you live on the north shore, eastern suburbs, or Sutherland     regions.


  • Timber — timber window frames are aesthetically pleasing and have good insulation properties. But, they require a good deal of maintenance, are easily damaged, and will reduce the lifespan of your windows.


  • uPVC — unplasticised polyvinyl chloride (uPVC) window frames have excellent insulation and acoustic properties. They are widely recognised as the Green Choice in window frames and require zero maintenance (apart from the occasional wipe) throughout their entire lifecycle. Even better they automatically create an airtight seal.


Here at Sydney Glazed Windows we specialise in uPVC double glazed windows. We love their outstanding surface finish and the wide variety of styles — there is something to can match any contemporary home or commercial building.


(D) Filler

What is sitting in between the 2 x window panes? Pressurised argon gas? Or just air? Make sure you ask these questions. Argon gas is a safe and odourless gas that is denser than air, and inside your windows it creates an additional barrier against the climate outside your house.


(E) Seal

In order for double glazed windows to deliver outstanding insulation and acoustic performance they need to be properly sealed. If you aren’t using uPVC frames (which have inbuilt airtight seals) make sure you ask how the glazier intends separating, spacing, and sealing the windows.

(F) Locks

Finally, the locking capabilities of the windows will also impact the overall price. Will you require key locks at multiple points? Or something simpler?


  1. Other Considerations

When asking for a quote from your local Sydney glazier be sure to research the company and ensure they have the proper skills and qualifications to install your double glazed windows correctly. You want confidence in their:


  • Expertise — are the glazier’s experienced professionals with proper qualifications?
  • Warranty — does the organisation offer a written warranty for the installation and performance of your double glazed windows?
  • Compliance — does the glass company ensure their windows, frames, and installation methods comply with Glass Standard AS 1288?


DON’T FORGET: the immediate performance and overall lifespan of your double glazed windows depends on the quality of the glass, seal, and filler between the layers of glass. Make sure your clear on all these things before placing your order.


  1. Double glazed windows Sydney price

Need an obligation-free quote for double glazed windows in Sydney? Get in touch with our expert team today for a personalised price that considers the unique needs of your home or commercial space. The professional team at Sydney Glazed Windows are committed to providing outstanding service for the entire lifecycle of your windows. Call us today.