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Replacement windows for a three-bedroom semi-detached house typically cost around £4,000. However, new windows prices are affected by factors like frame material and your chosen design. Double glazing can save up to £260 annually on heating bills – a reduction of around 20 per cent while triple glazing cuts bills by up to £360.
Our team of experts break down how installation, style, and materials impact the cost of double glazing windows. By consulting with the UK’s top 15 window companies, we provide the most up-to-date pricing data and offer top tips for securing the best deals on your new windows.
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To give you an idea of replacement window prices, we’ve compared the various styles and frame materials currently on the market and provided the average costs for double glazing in a seven-window, three-bedroom home. Our figures include the installation costs.
However, we recommend obtaining multiple quotes, as actual costs will vary depending on the installer you choose and the size of the windows required. It’s also important to be cautious of any quotes given before a property survey – any reputable installer will need access to your property to provide an accurate estimate.
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| Window type | Material | Average cost per window | Average cost for a three-bedroom house |
|---|---|---|---|
| Casement | uPVC | £525 | £4,000 |
| Casement | Aluminium | £1,054 | £7,500 |
| Casement | Timber | £1,581 | £11,060 |
| Sash | uPVC | £1,100 | £7,700 |
| Sash | Timber | £3,300 | £23,100 |
| Bow/Bay | uPVC | £1,700 | £11,900 |
| Bow/Bay | Aluminium | £3,400 | £23,800 |
| Bow/Bay | Timber | £5,100 | £38,700 |
When it comes to purchasing new windows, cost is a key factor. Our experts spent hundreds of hours examining the features, performance, and pricing of different window types, while also analysing customer feedback to help you make the most cost effective decision for your home.
As you look at replacement windows costs, you’ll find that the cheapest frame material available is uPVC (unplasticised polyvinyl chloride).
Affordable, durable and easy to maintain, uPVC windows are a great option if you’re looking for an alternative to more traditional timber and aluminium frames.
| Casement frame material | Small window* | Medium window** | Large window*** |
|---|---|---|---|
| uPVC | £527 | £597 | £650 |
| Aluminium | £1,054 | £1,194 | £1,300 |
| Timber | £1,581 | £1,791 | £1,950 |
uPVC window frames are one of the most cost-effective options for homeowners, offering durability, energy efficiency, and low maintenance at a lower price than timber or aluminium. On average, uPVC windows cost around £525 per unit, making them an affordable choice for those looking to upgrade without breaking the bank. Their long lifespan and excellent insulation properties also help reduce energy bills, providing additional savings over time.
Many manufacturers also offer wood effect or coloured uPVC frames but these tend to be more expensive than plain white.
Aluminium window frames are less popular than uPVC due to their higher cost, starting at £1,000 per unit, and lower energy efficiency. Despite being more expensive and less insulating, they offer a sleek, modern aesthetic and a robustness, making them ideal for larger windows and contemporary designs. While not as energy efficient as uPVC, their durability and low maintenance appeal to homeowners seeking a long-lasting, stylish option.
Timber window frames are a premium option compared to the price of uPVC windows. Timber frames start at around £1,500 per unit due to the natural material and craftsmanship involved. While they offer longevity, a classic, elegant look and strong insulation, the higher initial cost and ongoing maintenance–such as painting and weatherproofing–may make less affordable for many homeowners. However, for those seeking a timeless aesthetic, particularly for period homes, timber frames remain a popular choice despite the added expense.
Reduce installation costs by prioritising draughty windows. Installing a full set of new windows can reduce the cost of materials and labour, making it a more cost-effective option in the long run. However, if your priority is keeping costs to a minimum, you can choose to only upgrade the front-facing or most problematic windows in your home – such as those that are single glazed, leaky or damaged.
Double glazing can save you between £235 and £260 on your annual energy bill, with the biggest savings occurring over winter. Although it can take a few years to break even on new windows, you should see immediate improvements in your home’s draught-proofing and insulation, saving you money on your energy bills.
Casement windows are the most affordable designs, thanks to their simplicity. At the other end of the scale, bay and bow windows are the most expensive options, as they are more complex to manufacture and install.
| Casement window frame material | Small* | Medium** | Large*** |
|---|---|---|---|
| uPVC | £527 | £597 | £650 |
| Aluminium | £1,054 | £1,194 | £1,300 |
| Timber | £1,581 | £1,791 | £1,950 |
Casement windows are one of the most affordable options for homeowners, with frames starting at £500 per unit, offering significant savings compared to pricier timber or aluminium alternatives. Available in side, top, or bottom-hinged designs, they provide flexibility while remaining budget-friendly. Their simple yet effective hardware further enhances their cost-effectiveness, making casement windows a smart choice for those looking to replace windows without overspending.
| Sash window frame material | Small* | Medium** |
|---|---|---|
| uPVC | £1,100 | £1,180 |
| Timber | £3,300 | £3,200 |
Popular in period properties, sash windows are often installed in new builds to mimic the look of traditional architecture. Prices range from £1,100 to £3,200 per window, with the cost of uPVC sash windows being the lowest. While timber sash windows are significantly more expensive, with proper care they can outlast uPVC.
Since few manufacturers make sash windows with aluminium frames, your choice is usually limited to uPVC or timber.
| Tilt and turn window frame material | Small* | Medium** | Large** |
|---|---|---|---|
| uPVC | £550 | £570 | £655 |
| Aluminium | £720 | £850 | £1,020 |
| Timber | £1,000 | £1,111 | £1,500 |
Tilt and turn windows offer versatility and convenience, but they come at a higher cost than standard casement windows. uPVC tilt and turn windows typically range from £550 to £655 per unit, depending on size and design, making them more expensive than traditional options like casement windows. Their dual-opening function, which allows the window to tilt inward for ventilation or fully open inward for easy cleaning, adds to their appeal. While tilt and turn windows are a pricier investment, their functionality, ease of maintenance, and enhanced safety features make them a smart long-term choice.
| Bay window frame material | Small* | Large** |
|---|---|---|
| uPVC | £1,700 | £2,800 |
| Aluminium | £3,400 | £5,600 |
| Timber | £5,100 | £8,400 |
Bay windows are a stylish and desirable feature, but they come with higher costs due to their design. Typically made with casement or sash window styles, bay windows require paying for three or more individual windows, which increases the overall expense. The cost of bay windows in uPVC, typically ranges from £1,700 to £2,800, depending on design, making them more expensive than standard flat windows. However, the added light, space, and aesthetic appeal of bay windows often justify the higher cost, particularly in homes looking to enhance kerb appeal.A three bedroom property would generally only have the living room window as a bay, with the others being flat windows, thus reducing costs
| Bow window frame material | Small* | Large** |
|---|---|---|
| uPVC | £1,700 | £2,800 |
| Aluminium | £3,400 | £5,600 |
| Timber | £5,100 | £8,400 |
Bow windows, like bay styles, are more expensive because they consist of multiple window units–typically four or more–arranged in a curved design. Bow designs are often constructed from casement or sash windows, and prices typically range from £1,700 to £8,400, depending on the size of the installation, frame material and window style.
Although bow windows are available in timber, aluminium and uPVC, they are not offered by all manufacturers.
The main differences between double and secondary glazing are structure and price. Secondary glazing is the least expensive option because it doesn’t involve buying completely new windows. However, it’s not as energy efficient as double glazing, so you won’t experience the same savings on your energy bills. Triple glazing is the best for energy efficiency, but is the most expensive choice.
Double glazing is a popular choice for homeowners looking to improve energy efficiency, reduce heating bills, and add to their property’s value. Prices typically start at around £500 per window for uPVC frames, with timber or aluminium frames costing significantly more. For a semi-detached three-bedroom home, the cost of replacing windows with double glazing is around £4,000, however this varies based on the design, frame material, and any additional features, such as low-E coatings.
While the upfront investment may seem high, double glazing can save up to £260 annually on energy bills, making it a cost-effective long-term solution.
Secondary glazing involves adding an additional pane of glass or acrylic to the interior side of the window. Costs typically start around £150 per window, depending on the materials and design. While less expensive than full double glazed units, secondary glazing still offers some energy-saving and soundproofing benefits, making it a budget-friendly option for homeowners looking to upgrade their windows without the higher costs associated with complete replacements.
Triple glazing offers superior insulation and energy efficiency compared to double glazing, but it comes with higher costs. uPVC triple glazing typically ranges from £600 to £750 per casement window. However, some companies offer a triple glazing upgrade for the same price as double glazed windows.
Since triple-glazed units are heavier than double-glazed ones, properties may require wall reinforcements to support the extra weight. This can increase installation costs.
While the upfront costs are higher, triple glazing can significantly reduce energy bills and enhance home comfort, making it a worthwhile investment for homes in colder counties or those seeking maximum efficiency.
Several factors can bump up the cost of replacement windows.
Vera Cross and her son Jonny, both directors at Ultrabright Windows Ltd, share their advice on factors to consider.
“A standard white uPVC window costs from around £500; however the full quote depends on several factors, including the number of windows you’re replacing at once, their size, and any additional features you choose.
There are certain fixed costs associated with every job—for example, a Certass* certificate accompanies each installation, and there’s an administrative fee for that. Whether you’re replacing one window or ten, these fixed costs remain the same.
Therefore, I always recommend replacing at least four windows at a time, which is the number we can typically install in a day. This approach allows you to get a better rate per window than if you replaced four windows individually over time. It’s more financially beneficial to replace several windows or an entire elevation simultaneously due to the economies of scale.”
*Certass certification ensures that window installers’ work complies with building regulations, guaranteeing high standards of quality and safety.
With most companies, a team of two installers will fit your double glazing, working at an hourly rate of between £25 and £35 per person. This will amount to average labour costs of £500 per day. For a single installer, the day rate ranges from £200 to £280.
The length of time it takes to fit replacement windows on an entire property depends on the number of windows involved (as well as their size and type). As long as there are no issues, one window can usually be installed in up to three hours.
Bear in mind, too, that labour costs can vary by region. In the UK, prices are typically higher in London and the South East.
Before you contact any double glazing companies, take the time to research the various style options and materials available. When comparing different window quotes, you’ll also want to consider your budget, requirements and preferences.
Keep in mind that the cheapest quote may not represent the best offer.
An excessively cheap quote could mean the windows are made from inferior materials or that the company uses shortcuts in their installation or employs inexperienced staff. In time, these issues can lead to reduced durability, poor insulation or condensation between the panes. To protect yourself from unexpected repair bills or premature replacements, make sure to balance cost against quality. Ultimately, your windows should provide comfort as well as long-term energy savings.
To ensure you get the most from your investment in replacement windows, make sure to ask the right questions and compare quotes from reputable companies.
Find the best deal. Because everything from the style of the window to your choice of lock will affect the final price, most double glazing companies provide tailored quotes. By getting quotes from several companies, you can see who has the best deal, allowing you to negotiate.
Check that your installer is FENSA or Certass registered. This certification will be essential if you decide to sell your home in the future. A FENSA or Certass certificate indicates that new installations comply with building regulations and are registered with the local council. These certificates will also protect you should any problems arise with the installation.
To allow you to make an informed decision, any quote for new windows should be as detailed and transparent as possible. A professional installer’s quote should include the following details:
Before you sign the contract, ask the installer for clarification on anything you’re unsure about. By doing so, you can be confident in your decision about which supplier to hire for your windows upgrade.
Once you’ve made contact, a window company’s installers, suppliers or sales representatives will arrange an appointment to visit your home. During the visit, they will take measurements, discuss your options and provide you with an accurate quote.
Most window companies will use the exact measurements taken during their visit to produce your windows to order. Off-the-shelf window units are unlikely to be an exact fit, leading to draughts and dampness, and they may also have a reduced lifespan.Before you sign any contract, make sure you read the fine print, and never let a salesperson pressure you into making a snap decision. Any reputable supplier, such as Anglian, will allow you plenty of time to decide.
Most windows will need to be replaced after 15 to 20 years, but certain warning signs indicate that your windows are losing their efficiency:
By measuring your windows, you can get a good idea of the cost of replacement windows. This can also simplify the process of ordering new windows online or shopping for curtains or blinds. However, to prepare an accurate quote, your installer will also take detailed measurements.
If possible, measure your windows from the exterior of your property. Using millimetres, take all measurements from the edges of the bricks – you need to measure the window aperture (the hole in the wall that the window frame sits in) rather than the frame itself.
Some suppliers will request that you deduct 5-10mm from your measurements to allow for natural shifting. Check with your supplier to see if that’s the case.
Here’s a step-by-step guide to measuring your windows:
Yes, you can often negotiate a lower price on replacement windows. It’s advisable to get multiple quotes from different suppliers and use those as leverage in negotiations, and also inquire about any current promotions or discounts that might be available.
Recent increases in the prices of double glazed windows are due to higher production costs, labour shortages post-pandemic, and rising raw material and transportation expenses. However, government grants may help offset these costs if you meet specific criteria.
You can save money on material costs and labour by replacing all your windows simultaneously. Also, because your energy bills will increase if your windows become less efficient, you’ll improve your home’s overall energy efficiency by replacing all your windows in a single installation.
Yes, your choice of colour can affect the overall price of your replacement windows. White uPVC windows are the cheapest option, but the price can increase if you opt for a different colour or finish. For example, grey uPVC windows can cost around 10 per cent more than white ones. Choosing a wood grain finish can raise the total cost by around 10 to 15 per cent.
Premium windows offer superior energy efficiency, potentially saving you money over time by reducing heat loss and lowering energy bills, thanks to features like triple glazing and low-emissivity coatings. Additionally, they enhance noise reduction and come in various styles and durable materials, making them an attractive option for your home’s exterior. To decide, weigh these benefits against your budget and needs.
