Secondary Double Glazing FAQs
Below we have listed many common questions and answers related to secondary double glazing & soundproofing windows & doors. Simply click on a question to see the answer.
What is secondary double glazing?
Secondary double glazing is an additional layer of glazing that is added to an existing single glazed window. It involves installing a separate frame and window unit on the interior side of the existing window. The secondary glazing provides an extra barrier against noise, draughts, and heat loss, and is a far more cost-effective solution than replacing the entire window with a double glazed unit.
Does retro-fitting double glazing really work?
Yes it most certainly does! Our secondary double glazing products have been manufactured since 1970 (for the over 50 years!) and it is estimated that between 4.5 to 5 million windows have had our secondary double glazing retrofitted to existing windows & doors in Britain and Europe. And, we have literally installed thousands of windows & doors in Australia. Please see the references from Australian customers on our homepage.
Does secondary glazing require planning permission?
Basically, the answer is “No”, as we install a new window or door inside the existing window or door. This is why we are oftentimes the only option for double glazing in strata title properties & heritage listed properties where the exterior of the property cannot be modified.
The only exception is in the case where the door or window must be installed externally, which is very rare.
Can I install double glazing in a Heritage listed property?
As we install a new window or door inside the existing window or door, we make no modifications to the exterior of the property. This is why we are oftentimes the only option for double glazing heritage listed properties where the exterior of the property cannot be modified.
Do you remove all existing windows?
No we don’t remove your existing windows. Our secondary glazing System is screwed to the inside of your existing windows.
How to measure windows for secondary glazing?
If the secondary glazed window can fit inside the window frame (ie. the window handles don’t protrude too far) then measure inside the window frame.
If not, the window must be placed outside the window frame (called face fix). Then measure the window including the architrave at side, top & bottom.
Is secondary glazing cheaper than double glazing?
The simple answer is yes. Secondary glazing is typically at least 30% cheaper than traditional double glazing.
And it is logical because with secondary double glazing we only need to suuply one new pane of glass as compared to traditional double glazing where two new panes of glass are required.
Is your window frame fat and bulky?
No. In fact it is very slim. Our outer frame is only 36 mm from front to back. Often there is room to fit our window inside yours but if not we can fit it on the architrave.
How do you fit secondary glazed windows?
We typically install our secondary glazing with screws no more that 400mm apart. And all our door & window frames are discretely siliconed in to close any gaps.
Do you use glass in your windows?
Yes we use 6.38 laminated glass this is made up of 3 mm glass, interlay and then 3 mm glass, all heat bonded together. All our glass is bought locally and we have deliveries to our factory approximately every 48 hours.
After you have installed the secondary window will I be able to open my existing window?
We will design our secondary glazed window so it can be opened to give you access to your openers where it is required.
How long does it take to install a secondary glazed window?
Amazingly, it typically only takes approximately one hour to fit one of our secondary glazed window & then you can start obtaining the soundproofing & insulating benefits immediately. Additionally, there is little or no disruption as we do not have to remove & replace the existing window.
Can Secondary Glazing help stop, minimise or eliminate window condensation, moisture & mould?
Condensation often occurs on single pane windows, normally in bedrooms &/ or bathrooms where you have a single pane of glass which is cold on the outside & warm inside. The condensation occurs on the inside.
If you install a retrofittted secondary glazed window in the bathroom or bedroom, the new internal window would be the same temperature as the room, therefore drastically reducing likelihood of any condensation forming.
Can you tint Secondary Glazed windows?
So as to not effect acoustic or thermal performance, we recommend that if tinting is required, you tint your existing windows before installing our secondary glazed windows.
Are magnetic secondary glazed windows any good?
Magnetic secondary glazing involves installing a secondary window which is stuck to a frame around your existing window with magnets.
To open your window you have to physically remove the entire window. Just think about how would you go dealing with that … particularly for a large & thus heavy window … and what if you drop it!
We think in most cases that our solution is far better than magnetic secondary glazing. Contact us to find out why.
Double Glazing Windows & Doors FAQs
How much are double glazed windows?
Our secondary double glazed windows are typically 30% or more less than traditional double glazed windows as we don’t completely replace the existing window but rather add a sealed unit inside your existing window.
We charge as little as $500 m2 for double glazed windows manufacture, supply & installation (includes GST) in Melbourne.
What is a double glazed window?
A double glazed window is simply a window with multiple panes of glass with an air gap in between the panes of glass to aid noise reduction or soundproofing & reduced thermal transfer (ie. Less heat out in winter & heat in in summer).
There are two approaches to double glazing windows. The more expensive option is to completely replace the existing window with a new window with two panes of glass. Then there’s our much cheaper & less disruptive approach, where we simply fit a new window on the inside of your existing window.
What is double glazing?
Double glazing is simply having two panes of glass in your door or window to reduce thermal transfer & noise.
You can either have traditional double glazing where your existing windows are completely replaced by dual pane windows or doors, or our much cheaper and better soundproofing option where we install a new door or window inside your existing windows.
What's the best way to insulate windows?
The best and cheapest option for thermal & noise insulation for existing windows is with secondary double glazing.
We install a new window inside your existing windows. The large air gap provides excellent soundproofing & thermal transfer or insulation benefits and is typically 30% or more cheaper than replacing your windows entirely.
Does double glazing stop condensation?
Both traditional double glazing & secondary double glazing provide an insulating gap of air between two panes of glass, which will help reduce or stop condensation forming on your glass windows &/or doors.
However, secondary double glazing is a more cost effective solution (as we don’t completely replace your existing windows) & also, in the case where the seal deteriorates or breaks & condensation does form, our secondary double glazed windows &/or doors will allow you access to the interior gap to allow you to clean any water residue stains which may occur.
Can double glazing windows & doors be resealed?
If you have traditional double glazing & have this problem, you can buy a kit online, which enables you to drill a small hole in the glass top & bottom, blow air into the holes to ventilate the moisture out & then reseal the holes.
This problem does not occur with our secondary double glazing. This is just another reason why retrofitting secondary double glazing to existing woindows is the best option for doule glazing existing windows & doors.
Does DIY double glazing work?
It certainly is possible, but most DIY or Do It Yourself Double glazing solutions don’t allow you access to your existing windows to open and close them. This can be a limitation to your lifestyle.
Can you double glaze existing windows?
Absolutely you can add double glazing to existing windows. That is our speciality. We retrofit or secondary glaze your existing window with a new window on the inside of your house.
Retrofitting secondary glazing to existing windows provides better soundproofing & thermal insulation & eliminates drafts. And, because you’re only fitting one new pane of glass, it is usually more than 30% cheaper than completely replacing windows as is the case with traditional double glazing.
Can you double glaze sash windows?
We can retrofit double glazing to existing sash windows. We retrofit or secondary glaze your existing sash window with a new vertical sliding window on the inside of your house.
Retrofitting secondary glazing to existing sash windows provides better soundproofing & thermal insulation & eliminates drafts. And, because you’re only fitting one new pane of glass, it is usually more than 30% cheaper than completely replacing windows as is the case with traditional double glazing.
Can you double glaze Bay windows?
We can add double glazing bay windows. We retrofit or secondary glaze your existing bay window with a new window installed on the inside of your house.
Retrofitting secondary glazing to existing bay windows provides better soundproofing & thermal insulation & eliminates drafts as compared to traditional double glazing. And, because you’re only fitting one new pane of glass, it is usually more than 30% cheaper than completely replacing windows as is the case with traditional double glazing.
Can you double glaze leadlight windows?
We can double glaze existing leadlight windows. We retrofit or secondary glaze your existing stained glass leadlight window with a new vertical slider window or hinged panel window on the inside of your house.
Retrofitting secondary glazing to existing windows provides better soundproofing & thermal insulation & eliminates drafts as compared to traditional double glazing. And, because you’re only fitting one new pane of glass, it is usually more than 30% cheaper than completely replacing windows as is the case with traditional double glazing.
Soundproofing & Reducing Noise FAQs
How to soundproof a room?
Double glazing windows & doors is a great way to reduce noise and help soundproof a room.
For an existing property, our secondary glazing gives you better sound or noise reduction (Test results show a Sound Reduction Index of 45 decibels) due to a larger air gap and is typically 30% or more less cost than for traditional double glazing where the existing window is replaced in its entirety.
How to soundproof a door?
How to soundproof windows?
Double glazing is the best & most effective way to soundproof windows.
But for an existing property, our secondary double glazed windows, where we fit a new window to the inside of your existing window is by far the cheapest method of soundproofing windows & in fact gives better soundproofing due to a larger air gap between the panes of glass.
How to soundproof your apartment?
How to reduce noise in your bedroom?
How to reduce noise fom your neighbours garden?
And as we don’t completely replace your doors & windows our solution is typically 30% or more cheaper than traditional double glazing.
Why do sound proof windows work?
Using double glazing for sound proofing windows works because there is a sound insulating layer of air sandwiched between two panes of glass which disrupts sound wave vibrations.
Our secondary double glazing works better than traditional double glazing as the air gap is larger. Tests show we have a Sound Reduction Index of 45 dB (decibels).
Do you offer total soundproofing?
In a word, no. But, we have installed our secondary glazed windows with great results in Sound Studios & Music Studios.
So, if your son or daughter plays the drums & the neighbours complain, we can certainly help.
How to soundproof windows without replacing them?
What are the best windows to reduce traffic noise?
Double glazed windows can provide significant reductions in traffic noise, but, if you have existing windows retrofitted double glazing or secondary glazing is cheaper & a better solution for soundproofing, insulation & draft reduction.
With secondary double glazing we install a new, completely sealed window on the inside of an existing window.
How long does it take from placing an order to get the windows manufactured?
Manufacture is approximately 3 to 4 weeks. And remember, it only typically takes us one hour per window to install them.
Do you require a deposit?
Yes we require approximately 25% deposit before we will commence manufacture.
How do we pay the deposit and then the final balance?
We carry a mobile EFTPOS machine so we can take MasterCard, American Express, And Visa Cards. You can also do a online transfer directly into our bank and We also accept cash and cheque.