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The cost of double glazing can significantly impact your home improvement budget, but these windows offer substantial benefits, such as reduced bills, increased security and noise reduction. Double glazing prices vary based on several factors, making it essential to explore the different options, and there are also a number of window grants available to help maximise your savings.
Here, our experts explain the costs involved and how to choose the right double glazing company for your home, including tips on getting the best deals.
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It will cost around £4,500 to install uPVC double glazing for every window in a typical three-bedroom property. However, quotes will vary based on the window style, size, frame material and glass type. The number of windows is also a factor, but installers offer discounts for multiple upgrades.
| Type of three-bedroom property | Number of casement windows | uPVC | Aluminium | Timber |
|---|---|---|---|---|
| Flat | 4 | £2,108 | £3,200 | £4,800 |
| Terrace | 7 | £3,689 | £5,600 | £8,400 |
| Semi-detached | 10 | £4,500 | £8,000 | £12,000 |
| Detached | 15 | £7,500 | £12,000 | £18,000 |
Typically, uPVC frames are the most cost-effective option. They’re durable, require minimal maintenance and offer good thermal performance, making them a popular choice.
| Window material | Average cost for a casement window |
|---|---|
| uPVC | £525 |
| Aluminium | £800 |
| Timber | £1,200 |
Aluminium windows tend to be pricier than uPVC ones. Although they’re strong and require little maintenance, they aren’t as insulating as wood or uPVC, but they can be a good option for oversized windows that require more structural support. Composite frames, which are made from a blend of materials – often timber and uPVC – vary in price depending on the specific components used. They’re designed to provide the benefits of both materials. For example, timber and uPVC composite frames offer the aesthetic appeal of natural wood, and they come with lower maintenance requirements and provide good insulation.
Wooden window frames are typically the most expensive option. They offer excellent insulation and a classic look that many people love, but they require more maintenance to prevent issues such as rot and insect damage.
Different window styles have varying levels of manufacturing and installation complexity, all of which influence their prices.
Fixed windows, which don’t open at all, and casement windows, which only open from a single point – usually the side – are typically the easiest and cheapest options. Casement windows can also include the popular awning design, hinged at the top and opening outwards, creating an overhang. Sliding sash or tilt and turn designs that require more moving parts to allow them to open and close tend to come with a higher price tag.
Specialised architectural window styles, such as bay or bow windows, are the most expensive options. These designs project outwards from the home’s exterior and consist of several units – typically casement or sash. Custom frames, such as unusually large or non-standard shapes, can increase the cost, and the additional design and manufacturing work required for these windows can also make them pricey to install.
Bigger windows require more materials for the frame and glass, resulting in higher manufacturing costs.
Also, oversized windows can be more complex and time-consuming to install than smaller ones, leading to higher labour costs. For instance, more expansive windows usually require more people to install them due to their size and weight or the structural modifications needed to accommodate them, especially if installation requires the enlargement of an existing window opening.
| Window style and material | 600mm x 900mm | 900mmm x 1,200mm | 1,200mm x 1,200mm |
|---|---|---|---|
| uPVC casement | £500 | £580 | £620 |
| uPVC sash | £500 | £580 | N/A |
| uPVC tilt and turn | £600 | £695 | £750 |
| Aluminium casement | £800 – £1,000 | £950 – £1,150 | £1,200 – £1,250 |
| Timber casement | £1,500 | £1,700 | £1,850 |
| Timber sash | £1,500 – £1,700 | £1,700 – £1,900 | N/A |
If you’re looking for the additional benefits of increased insulation or highly break-resistant glass, then it may be worth considering a specialised glass, butmthese options can increase the cost.
Low-emissivity (low-E) glass is coated with a transparent, microscopic layer that reflects heat. This coating improves the window’s insulation, keeping your home cooler in the summer and warmer in the winter, but it generally costs more than standard glass.
Toughened or tempered glass is another costlier option, but it is stronger and safer than regular glass. If broken, it shatters into small, blunt pieces instead of large, sharp shards, reducing the risk of injury.
Laminated glass has a layer of plastic between two panes of glass, making it highly resistant to breakage. It also provides additional benefits such as noise reduction and UV protection, but these come at a price.
The number of windows you’re installing or replacing directly affects the project’s total cost.
However, it’s important to note that while the total price increases, there may be cost efficiencies when installing multiple windows simultaneously. For instance, labour costs may be lower, as installers are already on-site and have their equipment set up, so the additional time required to install more windows may not be significant. This means the cost per window could decrease with a larger project.
Some double glazing companies and suppliers offer discounts for larger orders, so the per-window cost might be lower if you buy several windows at once. However, potential discounts vary greatly and depend on the specific supplier or contractor.
Whether you replace all or just a few of the windows in your home will impact the final cost, so it’s worth considering if every window needs to be upgraded. If your windows are old or in poor condition, it makes sense to replace them all at once. After all, windows that don’t operate properly can pose a safety risk in an emergency.
However, if only some windows are damaged, you might just replace those ones. It’s not uncommon, for example, for windows on one side of a house to experience more wear and tear due to weather exposure. This could lead to them being less energy efficient, increasing household bills.
Triple glazing costs 10 to 20 per cent more than double glazing, but it offers increased insulation, so it may benefit properties in colder climates (for instance, in Scotland or the north of England). Some suppliers give free or discounted upgrades to triple glazing if you request a quote for double glazing.
The average cost of double glazing a three-bedroom house in the UK typically ranges from £4,000 to £7,000. However, several variables influence the price.
The number of windows to be replaced is a primary consideration. You may decide that not every window needs replacing, although some suppliers offer discounts for a full set of windows.
Equally important are the size and style of the windows required. Many homeowners choose more visually appealing styles for the front of the property, saving the less expensive options, such as casement, for the rear windows. Other factors that impact double glazing costs are the choice between a local or national window supplier and the complexity of the installation.
Double glazing is a valuable investment, thanks to its extensive benefits, including:
The potential energy bill savings of up to £235 annually ensure a rewarding return on investment.
The average double glazing cost and payback period for a three-bedroom property:
| Material | Average cost of double glazing a three-bedroom property | Average payback period |
|---|---|---|
| uPVC | £4,500 | 19 years |
| Aluminium | £8,000 | 25 years |
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Mark McCluggage, Director at Sheerwater Glass LTD, explained that most double glazing companies have to pay to provide insurance-backed warranties and register their windows with the Fenestration Self-Assessment Scheme (FENSA). However, once those fixed calculations are factored into the prices, there’s room for flexibility, meaning homeowners can often negotiate better quotes instead of having to accept the first figure given.
While the cost of double glazed windows has remained relatively stable for the last few years, there are several factors that could impact prices in the future. These include:
Decide how many windows you wish to upgrade
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Check that any professionals you hire have the necessary experience, qualifications and accreditations, including FENSA
Generally, your individual circumstances dictate the best time to purchase double glazing.
Purchasing windows during the off-peak season can be financially beneficial. This is often during the colder months when demand for installations decreases, and companies frequently offer discounts to maintain consistent business.
It’s also worth thinking about the energy cost considerations – having the installation carried out before winter allows you to benefit from energy savings during the colder months.
Double glazing is generally considered worth the investment due to several key benefits.
First, it provides significant energy savings. Double glazing insulates your home by trapping a layer of air between the two glass panes, reducing the amount of heat that escapes during the colder months. This can drastically lower your heating bills, helping the windows to pay for themselves over time. It also improves the comfort of your home, keeping temperatures more constant, reducing drafts and cold spots in the winter, and keeping the house cooler in the summer.
Double glazing reduces noise pollution by acting as a sound barrier, dampening the noise from busy roads, airports, or noisy neighbours, thus creating a more peaceful and quiet environment within your home.
New double glazed windows also improve the aesthetic appeal of your home, increasing its attractiveness to potential buyers. The energy efficiency and noise reduction benefits are another selling point.
Double glazing and triple glazing both aim to enhance a home’s energy efficiency and comfort, but they differ in construction, performance and price.
Double glazed windows have two glass panes separated by a gas-filled gap, reducing heat loss and external noise. Triple glazing adds an extra pane and gas layer, further improving insulation and soundproofing. While three panes offer superior energy savings, particularly in colder regions, triple glazing comes at a higher cost and increased weight, which may require stronger frames.
When negotiating with a double glazing salesman, clearly articulate your requirements and budget constraints, showing you’re informed and serious.
Several warning signs help to indicate that it’s time to replace your old windows with newer, more energy-efficient double glazed ones. These include:
It can be tempting to choose cheap double glazing, especially if you’re on a budget, but there are several risks and considerations to keep in mind before making a decision:
