Aluminium Windows Prices
How Much Do Aluminium Windows Cost in 2019?
Aluminium windows prices can vary, but you should expect to be paying from £150 to £450 per window. However, one important thing to remember is that the cost of your aluminium window is going to differ from company to company. Also, you could find that where you are in the country could have an effect too!
Aluminium windows prices are also dependent on their size, style, as well as how many you are looking to get installed. These factors are important to keep in mind when it comes to getting the best aluminium windows prices to suit you.
We understand this may be a lot to consider. So, what can you do to ensure you get a cheap aluminium windows prices?
The best place to start is to compare aluminium windows prices. If you take your time with this approach, you’ll be able to avoid any impulse buying that could see you worse off later down the line. Have a look around and see what your local installers can offer you, to help you keep the aluminium windows prices down.
Another way to keep things as quick and a simple as possible is to ensure you have your ideal aluminium window in mind. This means that you’ll have a good foundation to determine your price on, and you’ll be less vulnerable to hidden costs down the road.
What are the Starting Aluminium Windows Prices?
The cheapest aluminium windows usually start around the £150 mark, which is a vast difference to the higher end alternatives at around £450.
When it comes to aluminium windows prices, you can rest assured that even aluminium windows on the cheaper end of the spectrum are going to offer you an outstanding degree of performance as they are a highly modern window option.
Any design or styling changes, like the colour, size, or accessories, will add to the end aluminium window cost. Which is something you’ll need to keep in mind.
Do you want decorative glass?
Do you want additional thermal efficiency features?
What standard of security are you looking for?
Be prepared to pay extra for those!
Just like other home improvements, the size of the window also plays a huge role in determining aluminium windows prices.
Aluminium Windows Guide Prices 2019
What Are the Average Aluminium Windows Prices?
Pinning down a definitive aluminium windows price is a difficult thing to do, especially when there are so many variants for you to consider. With this in mind, you should be prepared to be flexible when it comes to aluminium windows prices.
With all of this in mind, we can offer you some guide prices to help you get an accurate frame of reference to work to. By using these prices, you’ll be able to have the confidence to approach your installer of choice with a good starting price.
Aluminium Window Prices (Fixed Window)
|Casement Window Size||Colour||Guide Price|
|500mm x 500mm||White||£150 – £175|
|500mm x 500mm||Wood Grain||£175 – £200|
|1000mm x 500mm||White||£175 – £200|
|1000mm x 500mm||Wood Grain||£200 – £250|
|1000mm x 1000mm||White||£200 – £250|
|1000mm x 1000mm||Wood Grain||£225 – £275|
|1200mm x 1200mm||White||£225 – £275|
|1200mm x 1200mm||Wood Grain||£250 – £300|
Aluminium Window Cost (1 Opener)
|Casement Window Size||Colour||Guide Price|
|1000mm x 500mm||White||£250 – £300|
|1000mm x 500mm||Wood Grain||£300 – £350|
|1000mm x 1000mm||White||£275 – £325|
|1000mm x 1000mm||Wood Grain||£325 – £375|
|1200mm x 1200mm||White||£300 – £350|
|1200mm x 1200mm||Wood Grain||£350 – £400|
|1200mm x 1500mm||White||£350 – £400|
|1200mm x 1500mm||Wood Grain||£400 – £450|
Instant Aluminium Windows Prices
At Double Glazing On The Web, we offer aluminium windows prices online. You can use our aluminium windows cost calculator to get an instant aluminium windows quote. You can also use the aluminium windows price tables used throughout this article for reference.
Aluminium Windows Prices: Comparing Local Installers and National Installers
To help get the best out of aluminium windows prices, we recommend comparing local and national orangery installers. This way, you’ll be increasing your opportunity for highly competitive prices. Through this method, you’ll also be able to ensure that you are completely happy with the company that you choose.
Both national and local installers are going to be able to offer you their own unique features and benefits. Whereas a local installer may be able to offer you more of a personal service all in all, a national installer may be able to utilise a bit more financial freedom to offer you a bulk or seasonal deal that will help you get better aluminium windows prices.
It’s important to keep in mind that aluminium windows prices are a highly competitive market, especially as aluminium windows have become a highly sought after home improvement option over the years. Due to their cutting-edge appeal and exceptional performance, it’s a good idea to see what sort of prices are on offer.
Why Should You Compare Aluminium Windows Prices?
In short, comparing aluminium windows prices is the pathway to getting a better deal to suit both your requirements and your budget. Alongside this, comparing and researching aluminium windows prices will also enable you to enjoy the peace of mind that comes with an informed decision.
Doing so also allows you to see what different companies can offer you when it comes to aluminium windows prices. This includes bulk deals and special offers that include accessories or discounts through certain window styles.
Aluminium Windows Prices and Energy Ratings
Aluminium windows, much like your comfort, are also dependent on thermal efficiency ratings. With this in mind, you could find yourself paying more for aluminium windows that sit higher on the Windows Energy Rating (WER) scale. This spectrum spans from an A-G scale, with the price lowering and increasing respectively.
Simply put, you can expect aluminium windows prices to be higher for windows on the ‘A’ scale than you can for windows on the ‘G’ scale. Speak to your installer of choice to see which standard of performance your aluminium windows will be achieving and from there you’ll be able to see how much you should be paying.
Glass and Colours
It isn’t only function and performance that are going to effect aluminium windows prices, the decisions you make on aesthetics are also going to make a difference. Aluminium windows are available in a wide range of glass choices and colour finishes, both of which could see you paying more for the window. This is because some glass options offer more technical features, whereas some colour options are a bit more specialist in their application.
Whether you choose toughened safety glass, thermal efficiency glass, self-cleaning glass, or simply a tinted option, your installer will be able to advise you on how it will change aluminium windows prices. The great thing about aluminium windows is the amount of freedom you have when it comes to how they look.
You can see the example aluminium windows prices online. Use our aluminium windows prices cost calculator to compare prices. If you are interested in colours other than white you can select these when creating your quote. Once you’ve got your price, we can put you in touch with three of your nearest accredited installers to help you get things on the move!
Alongside colour and glass, aluminium windows prices could also be affected by the hardware options that you choose. This will depend on the handle and hinges options that you choose, as well as the security hardware. The more specialist you choose, the higher you could be paying for your aluminium windows. So, keep this in mind when your specifying your window build.
What Aluminium Windows are The Best?
Aluminium windows, much like aluminium windows prices, vary greatly. So, with this in mind, there is no ‘best aluminium window’. This is because it’s more about the right fit, you may find that your home is better suited for the French window aesthetic rather than an aluminium casement window. Alternatively, you may find that the woodgrain look is more your style than a solid colour.
A standard aluminium windows range usually features a wide range of styles. This includes casement windows, tilt and turn windows, sliding sash windows, French windows, flush sash windows, and bow and bay windows. Each one these windows offers it own unique standard, so there is no reason to miss out on what you’re after.
The best way to find out which one is the best is to simply take a look at the stylings available. If you’re after something a bit more traditional, then you can opt for a flush sash aluminium window. Alternatively, if you want something that has more of a modern flair, then a beautiful casement window will be the ideal option for you to choose.
Does the Size of an Aluminium Windows Change Aluminium Windows Prices?
The size of your aluminium windows will change aluminium windows prices. To help with this, our price tables contain some standard sizing to help you get a feel for how the increase in size is going to create an increase in price. If you’re looking for a larger aluminium window, the you should expect to pay more for the materials and the installation time.
Aluminium Windows Prices Calculator
To enjoy aluminium windows prices that have been tailored to your exact specifications, you can use our aluminium windows cost calculator. This simple, free tool will enable you to follow a step by step process that enables you to get a quote that is based on your requirements.
Further to this, you’ll also be emailed a link to your quote so you can refer to it at a later date. Don’t worry, the quote isn’t set in stone. If you need to amend or add to your needs, you can do so. Feel free to take your time to get the best price for you.
It is important to note that aluminium windows prices you receive from our aluminium windows cost calculator are accurate to a high degree, they are also subject to change when it comes to the installer you choose. With this in mind, you should be prepared for the price to differ.
What Is Included with Aluminium Windows Prices?
Aluminium windows, unfortunately, are no exception when it comes to the possibility of hidden costs. However, there is no reason for you to worry about any of these when you are using Double Glazing on the Web as your conduit for your aluminium windows.
Our aluminium windows prices cost calculator protects you from any of these unpleasant surprises. You’ll be able to enjoy the benefits of an honest and transparent price that covers everything you will need to be paying for. This includes
The online quote you generate using our double glazing cost calculator will include:
A full technical survey
The style, size and colour of the product
Energy efficiency rating (whether A, B or C WER.)
Glass (a choice of standard, toughened or obscured.)
The full installation which includes all colour matched trims, fixings, silicones and sealants.
Registration with an industry body such as FENSA or Certass and relevant certification.
What are the Benefits of Aluminium Windows Prices?
Knowing aluminium windows prices is a good way to gauge the quality of your windows, as well as what you can expect to get with the cost.
It’s important to keep in mind that aluminium windows are an investment for your home, and one that you should expect to last. Alongside this, getting the right aluminium windows installed into your home could also see you saving money across the year! This is thanks to thermal efficiency, which will see the warmth from your central heating staying in your home for a longer period of time In turn, this means that you could find yourself with a lower heating cost as a result.
Further to this, aluminium windows prices can also be an indicator of how secure your property is going to be. Aluminium windows are inherently secure, even more so when they are fitted with high-security, multipoint locking systems. However, the better the lock the higher the price could be! But, it’s tough to put a price on peace of mind.
Why Choose Aluminium Windows?
Aluminium windows operate at the forefront of window design, combining premium grade materials, high performance hardware, and a stunning range to help you find the right option for you. Alongside this, they will also work to make your home a warmer, safer place to be. This is achieved through the highest standards of thermal efficiency, security, durability, performance, longevity, and aesthetics. They really are an impressive window that will leave a lasting impression.
Modern aluminium windows also bypass the poor thermal efficiency of their counterparts. This is achieved through a polyamide bridge that works to trap in pockets of warm air, stopping the warmth from your central heating from escaping. When this is combined with the high-security locking systems, which engage at different points of the frame, you know that you’ll be able to keep the cold and the intruders outside where they belong.
To ensure your aluminium windows do perform at their best, we only put you in touch with the best installers across the nation. This means that you’ll be able to benefit not only from premium quality, but also from the highest standards of professionalism, reliability, promptness, and complete respect for your home and for your time. At Double Glazing on the Web, we’ll be there to ensure that you don’t have to settle for anything less than the best.
How Do You Keep Your Aluminium Windows Prices Down?
We know that you want to bring the best to your home without having to spend an extortionate amount of money, right? Well, there are a few ways you can do this when it comes to aluminium windows price. One way to start is to source your aluminium windows prices from three different companies, based on the guide price we offer you.
As we mentioned earlier in this article, shopping around is a great way to make the most of the aluminium windows prices on offer. Make sure to get in touch with national and local installers alike, as you could be missing out on deals and discounts that you’re not aware of! Some installers will also offer you a better price if you’re getting a bulk deal!
Thirdly, haggling is also a great way for you to keep aluminium windows prices on the low. Keep in mind that many sales teams will want to get a sale from you via the first price, which is normally the highest. Don’t be afraid to negotiate a price! Use our guide quote as a benchmark to work from and you won’t go far wrong.
Frequently Asked Double Glazing Questions
Frequently Asked Double Glazing Questions
How much does it cost to replace a sash window?
The cost of replacing a sash window will depend on many factors including: style, size, material and glazing. A wooden sash window will cost significantly more than a uPVC sash window. A wooden sash window can cost up to £1000. Wooden windows are more expensive to manufacture so expect to pay that bit more. uPVC sash windows can be designed to mimic wood and are much cheaper in price. The starting price for a standard uPVC sash window is on average £525.
Can I install double glazing into my original sash windows?
This will depend upon what type of window you have. Replacing existing moving sashes with new, double glazed replicas might to be possible.
How much does sash window restoration cost?
The cost of sash window restoration will depend on the survey result. Standard draught proofed sash windows (without sill replacement) usually starts at about £500 per window. The time taken will also depend on the survey result.
Should I replace my old sash windows?
Sash windows are a key feature for many traditional period buildings. Sash windows were traditionally built using timber, which is fairly high maintenance and has a tendency toward rotting and warping. Over time, these windows can become draughty and insecure. uPVC sash windows are a great way to experience the benefits of modern double glazing, without sacrificing the aesthetic of your home. uPVC sash windows will not rot or warp and require little maintenance. They are also thermally efficient, which means that your home will not require as much heating.
How much does it cost to double glaze a 3 bed house?
On average a double glazed window will cost between £350 and £400, with a uPVC door typically costing £600. This means that double glazing a 3 bedroom semi can cost between £3500 and £5000.
How much does it cost to install a window?
The prices given in our pricing tables, our online quotes and our costing calculators reflect the price of the window itself as well as the cost of installation. For example, a 500mm x 500mm casement window will cost between £150 and £175 including the cost of installation.
Why Is uPVC Used For Window Frames?
UPVC is used for window frames because it strong, durable, energy efficient and long lasting.
Is Double Glazing Easy to Break?
No, double glazing is not easy to break which means your home will be more secure. When attempting to smash double glazing often what happens is that the first pane of glass and the second will remain intact. This is due to the argon gas working as a shock absorber. This will mean the smash is very loud but unsuccessful on the first attempt.
Is Double Glazing Worth It?
Double glazing helps make your home more energy efficient as it prevents the loss of heat. During the summer, it helps to keep the heat out of your home. It provides your home with sound insulation which is perfect for houses that are in busy areas and streets. Double glazing also makes your home safer and more secure.
How Long Does Double Glazing Last?
It is important to note that the argon gas that separates the panes of gas, giving double glazing its energy efficiency will eventually leak out overtime. Double glazing has an average life span of about 20 years, however, this can vary depending on materials used and the installation.
How Long Does It Take To Install A New uPVC Window?
Once you place your order for a new window, it takes 4-6 weeks to build and manufacture the product. On the day of installation it could take anywhere from 3 hours to a whole day, depending on size, shape and style of window.
How Do I Know If My Double Glazing Needs Replaced?
Double glazing will need replaced after a while due to the nature of the design – the gas that separates the two window panes slowly leaks out over time meaning the energy efficiency of your window is compromised. If your double glazing allows cold spots; water to seep through the frame; has cracks or chips in the window or has a build-up of condensation between the two panes of glass (misted windows), you should probably look into getting your double glazing replaced or repaired.
How Long Does It Take To Install A Window?
From the moment you purchase your window it will take anywhere between 4-6 weeks to build and manufacture your window for you. The actual installation itself could take anywhere between 3 hours to a full day.
Should I Double Glaze My Windows?
Double glazing works to make your house more energy efficient saving you money on your heating bills. Double glazing also provides sound insulation which is perfect if your house is situated near busy roads and noisy areas. Double glazed windows are also tougher and harder to break than single glazing windows making your house more safe and secure.
What Can Cause Double Glazing To Crack?
Double glazing can crack for what appears to be no particular reason at all. A sealed window unit faces constant pressure either side of the glass, however, most of the time double glazing is strong enough to deal with this. Winter can be one of the worst time for cracked glass as the difference of temperature on either side of the glass stressing it to the point it can crack.
Can My Windows Be Installed In Cold And Rainy Weather?
Yes, windows can be installed in any weather, however, it is important to remember the safety of the installers who come to put in your window and that the rain could damage things your property due to the fact there will be a hole in the wall for quite some time during installation.
Is uPVC Flammable?
No, uPVC isn’t flammable and is actually a fire retardant.
How Long Does It Take To Install uPVC Windows?
On installation day, a uPVC window will take anywhere from 3 hours to a full day depending on the shape, size and style of the window. When you place your order, it will take anywhere between 4-6 weeks to build and manufacture the parts for your bespoke window.
How Do I Know If My Double Glazing Needs Repaired?
There are four tell-tale signs that your double glazed windows need repair or replaced: There are chips and cracks in the panes of glass; there is condensation (misted windows) between the two panes of glass; the window allows cold air through; water begins to seep through the frame. If your double glazing does any of these things, you may need to get your double glazing repaired or replaced.
Does Double Glazing Block Sound?
Double Glazing not only provides heat insulation but it also provides sound insulation too. Double glazing is perfect for houses in busy areas and streets.
What Does Double Glazing Do?
Double glazing makes your house more energy efficient, keeping heating in and keeping the cold out during winter months. During summer months, it helps keep the hot air out, keeping your house cooler. It also works to insulate sounds from busy areas and roads, leaving your house more peaceful and quieter.
Is double glazing easy to break?
Double glazing is a strong option for windows compared to single glazing. The frames are durable and there are high security locking options. As double glazing is made from glass it is possible to break however you will have to exert quite a bit of force to do this. This is practically impossible to do without making a noise.
Is triple glazing better than double glazing?
In most instances double glazing will be an adequate upgrade to single glazed windows. Double glazing offers energy efficiency, noise reduction and security. If you live near a busy road or under a flight path you may want to consider triple glazing for the extra noise reduction that it can offer.
Is double glazing expensive?
Double glazing can be an affordable addition for many homeowners. The price you pay can depend on the quality of the windows and the energy ratings. Other factors are the style of the windows, the colour of the frames and the type of glass. Why not get an online double glazing quote to get an idea of the price.
What is the average cost to double glaze a house?
The average cost to double glaze a house will depend on the size of your house and the number of windows. To double glaze a flat or apartment it will probably cost around £2,000. The average cost to double glaze a house is usually between £4,500 to £7,500. If you collect a number of double glazing quotes you will be able to compare companies and prices.
How much is double glazing per window?
Double glazing prices per window can vary from around £150 to £600 depending on the specification. The window style, type of glass, frame colour and handles are all contributing factors. To find out the true double glazing price per window it is a good idea to get a number of quotes to compare.
What Makes Flush Sash Windows Different?
Flush sash casement windows are specifically designed to imitate the appearance of traditional wooden timber windows by appearing to have the same sashes that finish 'flush' with the outside face of the window.
Can Bay Windows Look Modern?
Bay windows can easily be either modern or traditional depending on the combination of glass and / or coloured uPVC profiles now available. Subsequently, its easy for these windows to seamlessly blend in with contemporary or old properties.
Bay or Bow Window?
Simply put, it really depends! Bay windows offer often much welcome and useful extra storage space to the frontage of homes. On the other hand, bow windows provide a curved shape alternative in terms of look compared to bay windows. They are both beautiful options and can add much character and charm to the right property.
How Much Do Aluminium French Doors Cost?
Unfortunately our online quoting engine does not quote for aluminium however you can get a price by calling one of our advisors on: 0800 015 5679. Or alternatively, you can contact us using our online enquiry form.
How Much Do Double Glazed Sash Windows Cost?
UPVC sash window prices will vary according to glazing style, your choice of locks and even your chosen colours and finishes. You can get an average sash windows cost using our window cost calculator.
Replacement Sash Windows In A Conservation Area
If your home is a listed property or within a conservation area then you will need to seek planning permission.
Why Should I Choose a UPVC Sash Window?
UPVC sash windows are incredibly attractive and make a stunning addition to any property and are relatively low maintenance thank to their UPVC design. You can enjoy a traditional aesthetic for many years to come thanks to their long standing properties.
Are UPVC Sash Windows Easy To Use?
UPVC sash windows are very easy to use. Their spiral balance mechanism allows for smooth operation so you can open and close your windows with ease. UPVC sash windows are also incredibly low maintenance and require very little cleaning.
How do UPVC Sash Windows Work?
UPVC vertical sliding sash windows are built to either slide vertically downwards or upwards. This opening function makes the UPVC sash window much easier to use compared to traditional wooden windows where the only choice is double hung and single hand.
How Much Do French casement windows cost?
The cost of French casement windows will vary depending on installer but you can get an average casement windows cost using our free online quoting engine
How Does The Tilt and Turn Window Mechanism Work?
The tilt and turn window can be ‘tilted’ inwards due to its unique turning action which allows the window to be easily accessed from both inside and out. All it takes is a swift turn of the handle.
Where Can I Get A Tilt and Turn Windows Price?
You can get a tilt and turn windows price using our window cost calculator which will give you a free and unique quote within a matter of minutes.
What is a Casement Window?
A casement window is attached to its frame by one or more hinges. A casement window is hinged at the side allowing them to open extremely wide. These windows can double up as emergency exits and are perfect for hard to reach places within the home, with many home owners installing these windows behind their kitchen sinks.
Can I Choose My Casement Window Handles?
Your double glazing installer will offer you a choice casement window handles and casement window hardware options so you can achieve the perfect look.
Are There Different UPVC Casement Window Sizes?
UPVC casement windows come in a wide range of sizes to suit your property. You can specify your casement window size in our window cost calculator to get a unique window price!
What Are Flush Casement Windows?
Flush casement windows are where the unit sits flush to the frame, creating a super sleek look.
Will I Have A Choice of Casement Window Locks?
A high security lock will be fitted as standard with your new casement window but your double glazing installer will also offer a choice of security upgrades.
Are There Other UPVC Casement Window Styles?
Other UPVC casement window styles include the French casement window which is a more traditional take on the standard casement style.
How Can I Get Casement Window Prices?
You can get instant casement window prices by using our free online quoting engine or you can contact us on: 0800 015 5679 to speak to one of our advisors.
How Long Will It Take To Install My Casement Window?
Because every job is different, it is best your talk to your double glazing installer who will be able to give you an exact timescale.
What Are U-Values?
A U-value measures how effective a window or door is as an insulator of heat. The lower the U-values the more energy efficient the aluminium window or door is.
What Colours Do Aluminium Windows Come in?
There is an infinite range of aluminium colours available for your windows and doors. The aluminium RAL colour chart consists of virtually any colour you could think of, allowing you to achieve the perfect look for your home.
How Long Do Aluminium Windows Last?
Aluminium windows have a long life span and should last about 20-30 years. Any type of window will require some maintenance but overall aluminium windows are extremely strong and durable.
Why Should I Choose One Of Your Installers?
All installers that operate in affiliation with Double Glazing on the Web are accredited by a recognised industry body such as FENSA or CERTASS. Double Glazing on the Web vet all of our double glazing installers to make sure you receive a professional and efficient quality service.
If I Use Double Glazing on the Web Who Will Fit My Double Glazing?
Double Glazing on the Web have a fully accredited network of local installers. Once you have created your free online quote we will put you in touch with up to three reputable local suppliers. Each of these suppliers will offer you a free no obligation quote and who you choose is completely up to you.
What Colour Options are Available?
There is a wide range of colour options available including both standard and bespoke colours and finishes. Aluminium windows and doors even come available in a RAL colour chart which gives you an infinite choice.
Do UPVC Windows Need Trickle Vents?
Trickle vents are not a requirement, however they do offer additional ventilation without the need for opening your windows so can be a valued add on.
What Does UPVC Stand For?
UPVC is an abbreviation for unplasticised polyvinyl chloride which is used in window frames.
Do UPVC Windows Look Cheap?
UPVC windows do not look cheap. They can be designed to offer slim sightlines and come in a wide variety of colours and finishes, not just the standard white. Authentic woodgrain finishes are available to achieve more of classic look.
Do UPVC Windows Discolour?
Your UPVC window will never rot, rust, peel or flake due to its long lasting material. An occasional wipe clean is all that is required.
Are Double Glazed Windows Good For The Environment?
Once of the best ways of making your home more energy efficient is insulation. Double glazed windows act as another layer of insulation, helping to prevent the loss of valuable heat.
Are Double Glazed Windows Soundproof?
Double glazed windows are built to provide improved sound insulation. Double glazed windows are recommended for homes situated on busy roads or built up areas where external noise can be a problem.
How Much Do Windows Cost?
Window prices will depend on your specifications such as size, style, glass type and security locks. At Double Glazing on The Web you can get an instant window cost online using our online quoting engine. Simply choose your window style and enter your window measurements to receive a unique window price.
What Are Double Glazed Windows?
Double glazed windows feature two panes of glass for better heat insulation and noise reduction. Window frames come in a variety of materials such as UPVC, wood and aluminium. Double glazed windows also come in a choice of styles to suit your home, you can choose from a wide range of window designs which include the casement window, tilt and turn window, sash window, sash horn window and bay window.
What Happens if I Have a Problem with my Windows or Doors?
All of the double glazing installers in our network offer product guarantees. Provided you are still covered by your manufacturer's guarantee, all you need to do is contact the installer in question and they will either repair or replace your windows and doors.
Condensation on Double Glazed Windows
When moisture in the air suddenly cools and condenses on a cold window, you get condensation. Well insulated (Low E) double glazing will help prevent condensation from forming on the interior of your window. Replacement glass units or replacement double glazed windows are recommended for windows with condensation.
How Does Double Glazing Work?
Heat loss is greatly reduced using double glazing. Double glazing features two panes of glass with a layer of trapped air or gas in-between. Air is a poor conductor of heat so much less heat is lost through the window itself.
What is Double Glazing?
Double glazing is where windows have two layers of glass with air tight gap between them to reduce loss of heat as well as provide effective noise insulation.