The average window replacement cost using white uPVC casements – the most economical in terms of material – is around £4,000, but swapping older windows for new double glazing can save up to £235 on annual heating bills. 

With a variety of replacement double glazing windows options available, finding the perfect balance between quality and affordability is easier than ever. Our experts dive deep into the factors influencing windows prices, offering essential insights and tips on navigating the market for the best deals.

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What are the cheapest materials for window frames?

The cheapest frames are unplasticised polyvinyl chloride (uPVC) casement windows. This is because of their budget material and scale of mass production. However, while wooden frame have the most expensive initial cost, timber windows can last at least twice as long as uPVC windows (if not even longer) making them a cost effective option if you plan to remain in your property for more than 25 years. 

However, with timber you will need to budget for regular maintenance, which neither uPVC nor aluminium requires.

uPVC windows prices

white upvc windows in brick house

uPVC windows are one of the cheapest options and suit more modern properties. They are generally available in a range of styles and colours. (Image credit: Adobe)

White uPVC windows are a popular and cost-effective choice for residential properties, with prices starting at £500 per casement frame. However, uPVC frames are available in various colours, finishes and styles, making it easy to find a design that complements your property’s aesthetic.

uPVC frames provide good insulation, helping to reduce heat loss in the winter and heat gain in the summer, resulting in lower energy bills and increased comfort within the home. They also require little maintenance – just a wipe-over with soap and water – and are resistant to moisture, rot, and UV damage, meaning they will not warp, crack, or fade over time. uPVC windows generally last around 25 years before needing to be replaced.

Casement window frame material600mm x 900mm900mm x 1,200mm1,200mm x 1,200mm
uPVC£500£580£620

Aluminium windows prices

Aluminium windows prices are reasonable and can achieve a sleeker and more contemporary aesthetic in a house design. (Image credit: Adobe)

Aluminium windows are more expensive than uPVC, with prices starting from £1,000. However, they are generally more affordable than high-end materials, such as timber.

Aluminium has a high strength-to-weight ratio, allowing for slim frame profiles without compromising structural integrity. This results in larger glass areas and more natural light entering the building. It also requires minimal maintenance, and is rust-resistant and warp-proof.  

However, aluminium has one significant drawback: a lower energy efficiency than materials like uPVC or wood. It is a thermal conductor, potentially leading to higher energy bills and less comfortable interior spaces. To address this issue, manufacturers often incorporate thermal breaks (a low thermal conducting material to reduce transfer of hot or cold) into the design of aluminium window frames to improve their insulation properties. Aluminium frames have a lifespan of around 45 years.

Casement window frame material600mm x 900mm900mm x 1,200mm1,200mm x 1,200mm
Aluminium£1,000£1,150£1,250

Timber windows prices

traditional stone cottage with timber windows and thatched roof

Period properties typically suit timber windows better, but this material can also be used in newer homes for a sustainable and better insulated choice. (Image credit: Adobe)

Timber frames are the most expensive option, with prices starting at £1,500, which may be beyond reach for those on a tighter budget. Compared to uPVC or aluminium, timber frames require regular ongoing maintenance, such as oiling or repainting, which can add to the cost.

However, while more expensive upfront, timber windows may offer a higher level of thermal insulation and durability and can lend better aesthetic value to properties, particularly period homes. Therefore, depending on the property and the long-term plans of the homeowner, investing in timber window frames may offer value for money over time, despite the high upfront costs. 

Casement window frame material600mm x 900mm900mm x 1,200mm1,200mm x 1,200mm
Timber£1,500£1,700£1,850
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Maintenance vs upfront costs

Wooden window frames can deteriorate over time due to weather and use. To keep them in top shape, it’s important to repair, repaint, or revarnish them every one to five years, depending on the wood type. Fixing wooden frames can take two to six hours per window and cost around £100 if you’re a confident DIYer.

  • Installing new uPVC windows in a typical three-bedroom house averages £4,000, with minimal upkeep costs, and they last around 20 years.
    • This equates to about £200 a year 
  • Well-maintained wood windows will last at least 40 years with an initial cost of £8,000 for the same size house 
    • A five-year maintenance plan for eight windows equals £6,400 over their lifetime. Added to the initial cost, makes the total £14,400 
    • Divided by a lifespan of 40 years, gives an annual figure of £360 

This means that the average cost for wood windows is only £260 more than for uPVC options, taking longevity and maintenance into consideration. 

What is the cheapest style of window?

Numerous window styles are available to suit different architectural designs, personal preferences, and functional requirements. Many homeowners choose classic casement windows for their affordability, functionality, and versatility, but they don’t suit every property. Cottages, for example, may suit bay styles, while sash windows are more in keeping with Georgian properties.

Casement windows prices

white casement windows interior view with brass handles

Casement windows are a classic choice for any style of home – they can be designed to open from the top, bottom or side. (Image credit: Adobe)

A casement window is hinged on one side and opens outwards using a crack or lever as the operating mechanism. They are popular due to their versatility, ease of use, and ability to provide excellent ventilation. They also offer an unobstructed view as there is no central rail and, by creating a tight seal when closed, casement windows can provide better security and energy efficiency.

A uPVC casement window is the most commonly-seen option, but they can also be made from aluminium or timber and customised with different finishes, colours and hardware. Many designs incorporate internal bars to give the impression of individual glass panes or small vent windows, which can be fitted with stained glass for additional interest.  

However, casement windows may not be suitable for all situations, such as spaces where an outward-opening window would be obstructed or pose a safety hazard.

Casement window frame material600mm x 900mm900mm x 1,200mm1,200mm x 1,200mm
uPVC£500£580£620
Aluminium£1,000£1,150£1,250
Timber£1,500£1,700£1,850

Sash windows prices

clack painted sash windows in brick building

Sash windows typically open vertically, but horizontal sliders can be found in Yorkshire and Cornwall. (Image credit: Adobe)

Sash windows, often known as a hung sash or sliding window, originated in the late 17th century. They consist of one or more movable panels called sashes. These sashes slide vertically (in single-hung or double-hung sash windows), using counter-weights, or horizontally (in sliding sash windows) within the window frame, allowing for easy opening and closing.

Sash windows are frequently seen in Georgian, Victorian, and Edwardian-style buildings. They provide an elegant and timeless appearance, and modern double glazed versions are energy-efficient and easy to maintain, making them a popular choice for both traditional and contemporary homes. Beware, however, that the number of panes in a historic sash will depend on the property’s date of construction, although there are no absolute rules. Georgian homes, for instance, typically feature a “six-over-six” configuration, while Victorian terraces are usually seen with “one-over-one” sash designs. They are available in uPVC and timber and can include different colours and finishes. 

Sash window frame material600mm x 900mm900mm x 1,200mm
uPVC£500£580
Timber£1,500£1,700

Bay windows prices

window seat in bay window with orange curtains

Bay windows are very desirable as they let in light from multiple directions and provide an increased internal footprint. (Image credit: Adobe)

Bay windows project outward from the main walls of a building, forming a recess or a “bay” in the interior space. This design creates an expanded view and allows more natural light to enter the room. Bay windows are popular in residential properties for their aesthetic appeal and functional advantages.

They typically consist of three or more individual windows joined together at angles, creating a curved or polygonal shape. The central window is usually larger and parallel to the main wall of the building. The side windows, called flankers, can be set at various angles, such as 30, 45, or 90 degrees, depending on the desired effect and architectural style.

Bay double glazed windows can be found in various styles and configurations and constructed using different materials, but the most popular are timber, uPVC, or aluminium. There are no standard fixed sizes for bay windows, but generally, the prices are based on casement styles, with an additional £75 per panel to cover the connecting struts. The figures shown below provide a guideline.

Bay window frame material1,016mm x 914mm3,200mm x 1,980mm
uPVC£1,700£2,800
Aluminium£3,400£5,600
Timber£5,100£8,400

Bow windows prices

Bow designs are rounder than bay windows and can be seen with four of five window units. (Image credit: Adobe)

Bow style windows are similar to a bay, projecting outward from the main wall of a property and creating additional interior space while allowing more natural light to enter the room. The key difference between the two lies in their shape and configuration.

As the name suggests, a bow window consists of a curved or semi-circular arrangement of windows, typically four or more, that are joined to form an arc. This creates a rounded appearance on the exterior of the building and a curved nook or alcove in the interior space. The individual panels in a bow window are usually of equal size and may be fixed or openable, such as casement or double-hung windows.

There are no standard sizes for bow windows, with each design tailored to your requirements. The prices are based on casement panels, with an additional £75 per panel to cover the connecting struts and poles. The table below provides a guideline.

Bow window frame material1,016mm x 914mm3,200mm x 1,980mm
uPVC£1,700£2,800
Aluminium£3,400£5,600
Timber£5,100£8,400

Tilt and turn windows prices

large black aluminium tilt and turn windows above radiators in white room

Tilt and turn windows offer more versatility than casement windows as they can open fully, or tilt from the hinge for ventilation. (Image credit: Adobe)

Tilt and turn windows are growing in popularity thanks to their versatility and modern appearance. They feature a hinge system that allows them to either tilt inwards, pivoting from the top, middle or bottom of the frame, or swing open like a regular casement window. The former option doesn’t compromise the property’s security and is especially useful if you have young children. 

Tilt and turn double glazed windows are energy-efficient and easy to maintain. They can be found in various materials, including uPVC, aluminium, and wood, and are suitable for both residential and commercial applications.

Tilt and turn window frame material800mm x 800mm1,000mm x 1,000mm1,200mm x 1,200mm
uPVC£600£695£750

How to measure for new or replacement windows

woman measuring steel windows

It is always best to measure window sizes twice to be sure of accuracy. (Image credit: Adobe)

When planning new or replacement windows, accurate measuring is crucial to ensure a proper fit and prevent installation issues. Always measure the aperture – the hole in the wall the window sits in – rather than the window itself. It’s always best to do this on the exterior of your property, if possible.

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Measuring windows step-by-step guide

  1. Gather the necessary tools: You will need a tape measure, a pen or pencil, and a piece of paper to note down the measurements.
  2. Measure the width: To obtain the correct width, take three horizontal measurements – at the top, the middle, and the bottom of the aperture. Record the smallest of the three measurements as the width. This accounts for any irregularities or imperfections in your property’s brickwork or the squareness of the window.
  3. Measure the height: Measure the window aperture vertically. Again, take three measurements – one on the left, one in the middle, and one on the right. Record the smallest of the three measurements.
  4. Check the aperture angles: To ensure your window aperture is square, measure the diagonals from one corner to the opposite corner. The two diagonal measurements should be equal or very close to equal. A significant difference between the two diagonal measurements may indicate that your aperture is not square.

Remember, it’s always a good idea to double-check your measurements for accuracy. Consult a professional window installer if unsure about your measurements or the process. They will usually check your measurements before confirming a quote, and visit before installation begins, too. 

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What is your primary reason for installing double glazing? (FMB)

Should I choose double glazing, triple glazing or secondary glazing windows?

Double, triple, and secondary glazing all have specific advantages and disadvantages, so choosing between them depends on your circumstances.

Double glazing

The term double glazing refers to a sealed unit consisting of two panes of glass with a space between them, typically filled with an inert gas, such as argon. This gap creates an insulating barrier which reduces heat transfer and sound transmission. They offer several advantages for the homeowner:

  • Energy efficiency: The most significant benefit of double glazing is improved energy efficiency, compared with that of single glazing. The insulating barrier reduces heat loss in winter and heat gain in summer, leading to lower heating costs. Our survey shows that for almost 94% of homeowners, this is a primary reason they are having double glazing installed. 
  • Noise reduction: Double glazing effectively reduces external noise, making it an ideal choice for homes near busy roads, airports, or urban centres. According to our survey, for over 31% of people, noise reduction is a primary consideration for their double glazing installation.
  • Condensation reduction: The insulating gap minimises condensation on the inner pane, reducing the risk of mould and dampness.
  • Enhanced security: Double glazed windows are more robust and harder to break than single-pane windows, offering an additional layer of security.
  • Property value: The energy efficiency and noise reduction benefits of double glazing can increase the value of your property by up to 10%.
  • Aesthetic: Double glazing is often considered more visually appealing, enhancing the overall appearance of a property.

According to our survey, 25% of homeowners considering installing double glazing throughout their property in the next year expect to pay between £3,000 and £4,000. Another 25% are considering replacing their faulty windows for between £1,000 and £2,000, while almost 13% plan to spend over £5,000.

How much do you plan to spend on having double glazing installed? (FMB)

Triple glazing

Triple glazing involves using three panes of glass within a window unit. This design significantly enhances a window’s insulation properties, trapping more heat inside a building and keeping the cold out. 

It’s particularly effective in colder countries, such as the Baltic regions, where retaining heat is crucial. Triple glazing is also beginning to make a big impact in the UK, with updated building regulations under the government’s Future Home Standard project becoming mandatory in 2025. These updates will require new builds to produce 75–80% less carbon emissions than homes built under the current regulations and could include triple glazing as one of the energy-efficient measures. 

Triple glazed windows offer homeowners a number of advantages over double glazing.

  • Improved insulation: The most significant benefit of triple glazing is its superior thermal insulation. The extra pane of glass, along with the gas-filled spaces between them, greatly reduces heat loss, making your home more energy-efficient.
  • Noise reduction: Triple glazed windows generally offer excellent sound insulation. They effectively reduce external noise, making them ideal for homes in noisy environments.
  • Reduced condensation: The improved insulation properties also reduce the likelihood of condensation forming inside the window, which can be a problem with double glazing in very cold weather.
  • Increased security: The additional pane of glass makes these windows more difficult to break, offering enhanced security compared to single or double glazed windows.

There are also a few drawbacks to triple glazing. 

  • Cost: Triple glazed windows cost between 10 and 20% more than their double glazed counterparts; however, some suppliers offer free or discounted triple glazing upgrades.
  • Weight: The additional pane of glass adds extra weight – up to a third more, which can be a consideration in some installations. This may require reinforced or more robust window frames.
  • Light reduction: With an extra pane of glass, there can be a slight reduction in the amount of natural light entering the room.
  • Challenging for repairs or replacements: Repairing or replacing a triple glazed window can be more complex and costly than a double glazed one.

Secondary glazing

Secondary glazing involves attaching a separate pane of glass or plastic to the inside of the existing window frame using a magnetic strip with an air gap between the original window and the secondary glazing. It’s particularly useful for listed buildings or those within conservation areas, where alterations to the property’s external appearance are restricted. 

Although generally less efficient than double glazing, secondary glazing provides improved thermal insulation and noise reduction. It also has three other advantages:

  • Installation: Secondary glazing can be installed as a DIY project or by a professional. It is generally more straightforward and quicker to install than double glazing.
  • Cost: Secondary glazing is generally cheaper than double glazing, but it may not provide the same level of long-term energy savings.
  • Acoustic insulation: It is generally accepted that secondary glazing can offer good sound insulation, in some cases better than double glazing.

If you’re considering installing secondary glazing, there are some disadvantages to factor in: 

  • Reduced natural light: By adding an extra layer to your windows, secondary glazing can reduce the amount of natural light that enters your home. This may make your living spaces feel darker and less inviting.
  • Ventilation issues: Adding an extra pane can limit the ability to open and close windows easily, potentially reducing airflow and ventilation within the home. This can be particularly problematic in rooms with high humidity, such as bathrooms and kitchens.
  • Condensation: Secondary glazing can lead to condensation forming between the primary and secondary panes, especially if the installation is faulty. This can reduce visibility and contribute to the growth of mould and mildew.
  • Cleaning and maintenance: Having an extra pane can make cleaning and maintaining your windows more challenging, as you need to consider both the primary and secondary panes.
  • Aesthetics: Adding a second pane can be visually less appealing than double glazing, as it may not be as neatly integrated into the existing window frames. It can also create a “double reflection” effect that some people find distracting.
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What to consider before getting windows quotes

When assessing the cost of new or replacement windows for your home, you’ll want to take several factors into account. Start by assessing your home’s specific needs and requirements, such as the level of insulation, noise reduction, and security you’re seeking. You should also consider the type of window frames and glazing that best suit your home’s style and your personal preferences.

Research companies

Next, research different window manufacturers and suppliers to find the best double glazing companies. Look for companies with good reviews, certifications (namely, FENSA), and warranties to ensure you’re getting a high-quality product. It’s also wise to compare quotes from multiple suppliers to find the best value for your investment, rather than simply the cheapest, and resist feeling pressured to commit to a quote based on “on-the-day” prices.

Types of glass

The type of glass used in double glazed windows can also affect their performance. Look for windows with low-emissivity (Low-E) glass, with a special coating that helps reduce heat transfer and improve energy efficiency. Consider the type of gas (argon, krypton or xenon) used to fill the space between the glass panes; argon is the most common and affordable choice. Also consider the window’s energy efficiency rating, which should be displayed on a label or in the product specifications.

Installation quality

In addition to the windows themselves, consider the quality of the installation. A poor installation can negate the benefits of high-quality windows, so hiring an experienced and reputable company is crucial to ensure the job is done right. Ask for recommendations from friends, family, or online reviews.

Finally, ensure the windows you choose meet any local building regulations or requirements, particularly if you live in a historic or conservation area. This may involve seeking permission from local authorities before proceeding with the installation.

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Replacement windows in heritage, or listed, properties

Replacing windows in heritage or listed properties involves a unique set of challenges and extra costs to consider. Such properties are protected due to their historical significance, meaning any alterations, including window replacements, must preserve the building’s character and appearance. Given the need for permissions, architects, and specialist craftsmanship, the costs associated with replacing windows in listed properties can be significantly higher than standard window replacement projects.

Seek Listed Building Consent 

Before undertaking any work, obtaining the necessary permissions from the local planning authority is crucial. For listed buildings, you will need Listed Building Consent for any changes that might affect the property’s character as a building of particular architectural or historic interest. Listed Building Consent is free, with your local authority covering the cost. Before applying, consider: 

  • Regulatory compliance: It’s important to familiarise yourself with the specific regulations and guidelines set out by heritage bodies, such as Historic England, Historic Environment Scotland, Cadw in Wales, or the Northern Ireland Environment Agency. These organisations provide valuable guidance on maintaining and altering listed buildings.
  • Expert advice: Engaging with architects or surveyors who specialise in historic buildings early in the planning process can provide invaluable advice and help navigate the regulatory landscape.

 

Apply for planning permission

Permission to fully replace windows might be approved due to irreparable damage, such as extensive rot or decay, making restoration impractical. Alternatively, if previous replacements compromised authenticity by using incorrect materials or designs, proposing a return to the original style can also serve as a legitimate basis for replacement.

For small projects, local authorities typically aim to make a decision within two months, while more significant projects may take up to 13 weeks to process.

Homeowners can design and submit their own detailed drawings to the planning department, but most are submitted with the help of an architect. This can cost between £900 and £1,500. Additional costs might be affected by:

  • Specialist suppliers: Due to the need for precision in matching historical styles, sourcing windows from specialists in heritage properties is often necessary. These suppliers can provide windows that meet the aesthetic and functional requirements of historic buildings.
  • Need to match the original: Replacement windows must closely match the original windows in material, design, and construction method. In many cases, this means using traditional materials like wood rather than modern alternatives like uPVC.

What should a quote for new or replacement windows include?

A quote for double glazing should be comprehensive, easy to understand and provide a detailed breakdown of the costs and services involved in the project. 

  • Window specifications: Any quote needs to clearly describe the windows, including the style, size, frame material, glass type, and any additional features, such as Low-E coatings or gas fills. It should also specify the number of windows being installed.
  • Cost of materials: The new windows’ cost, frames, and any additional components, including locks, hinges, or handles, must be itemised.
  • Installation cost: The quote should clearly outline the labour costs for the installation, which may be charged as a flat fee or on a per-window basis. Any necessary work to remove old windows, prepare the apertures, and install costs of new windows should be listed.
  • Additional work: If any extra work is required, such as repairs to window apertures or frame modifications, the quote should estimate these costs.
  • Waste disposal: The quote should specify if the cost of disposing of the old windows and any construction debris is included or if there will be an additional charge for this service.
  • Optional extras: If there are any optional extras, such as upgraded locks or decorative features, the quote needs to list the associated costs separately so that you can easily compare the base quote to the upgraded options.
  • Estimated timeline: There needs to be an estimated timeline for the project, including when the work is expected to begin and how long it will take to complete.
  • Payment terms: The quote should outline the payment terms, such as the deposit required, the schedule for progress payments, if applicable, and the final payment due upon completion.
  • Warranty and guarantee information: The quote needs to show any warranties or guarantees provided by the window manufacturer and the installer, including the duration and coverage of these protections.
  • Licensing and insurance: The quote should confirm the installer is licensed and insured; this is important for your protection in case of any installation issues.

Before accepting a quote, review it carefully and ask any questions you may have. Getting multiple quotes from different suppliers and installers is also a good idea to ensure you’re getting the best value for your investment.

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Double glazing expert insight - Richard Tincknell, Britannia Group

Tincknell has been with the Britannia Group for over 30 years. He claims that less reputable double glazing companies sometimes advertise unachievable low prices on their websites to draw customers in, while others give time-limited deals to pressure people into signing. 

 

However, trustworthy installers should be keen to ditch the pushy salesman image. Richard explains that it’s crucial for customers to have a good experience from initial contact to the finished installation.

 

Through advanced technology, customers can instantly see how a particular window will look incorporated into their home to ensure they are happy with their quote. The choice of frame materials, style, colour and window furniture all impact the final prices. This design view allows customers to easily adjust their order according to their preferences and wallets.

When should I replace my windows?

Knowing when to replace double glazed windows involves assessing several key factors.

  • Condensation between panes: Condensation or fog between the panes of glass is a sign that the seal has failed and moisture is getting in, reducing the window’s insulating properties.
  • Noticeable draughts: Draughts coming through the window even when it’s closed means that the sealant around the window might be failing or the window frame may have deteriorated.
  • High energy bills: A significant increase in your heating or cooling costs could be due to the windows losing their insulating properties. Upgrading to more efficient windows can help reduce these costs.
  • Soundproofing fails: If outside noise seems louder than it used to be, the windows may not provide adequate sound insulation.
  • Mechanism issues: Windows that are hard to open, close, or lock can be a sign of warping or structural issues, which can impact both security and insulation.
  • Visible damage: Look for any cracks in the glass, as well as rotting or warping in wooden frames, or rusting in metal frames. Physical damage can impair both the functionality and aesthetics of your windows.
  • Age of the windows: Double glazed windows that are over 20 years old might be less efficient due to advancements in window technology. Newer models offer better energy efficiency, security, and noise reduction.

How we made this article

In creating this article, our team of expert researchers embarked on a comprehensive and rigorous process to ensure accuracy, drawing on credible, authoritative sources. Spending over 200 hours on research and analysis, we aim to help you make an informed decision regarding window prices.

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