TL;DR
- Most fitted windows in 2026 land between £600 and £2,500 each, with whole-house replacements typically £6,000 to £20,000 depending on property size, material and specification.
- uPVC suits most 1960s to 2000s homes; aluminium suits contemporary properties; timber is the right call for period homes; secondary glazing protects listed buildings and original sashes.
- Quality double glazing is the right balance for most UK homes. Triple glazing rarely justifies its 25 to 40 per cent premium outside passive house or extremely exposed locations.
- Compare quotes line by line, not headline by headline. A complete quote includes survey, scaffolding, disposal, making good, trickle vents, FENSA or CERTASS certification, and clearly stated warranty durations.
Replacing the windows on a UK home is one of the largest discretionary spends most homeowners ever make, and one of the easiest to get wrong. The brochure prices look simple enough, but the actual numbers on a final invoice depend on a long list of variables: the material, the style, the glazing specification, the colour, the hardware, the condition of the existing openings, the access to the property, and what the surveyor finds when they actually arrive. Two homes on the same street can pay £4,000 apart for what looks, on paper, like the same job.
This guide cuts through the noise. We will walk through what new windows genuinely cost in 2026, what drives the price up or down, and where homeowners most often get caught out by quotes that look cheap until installation day. Whether you are replacing eight tired uPVC casements on a 1990s semi or specifying timber sashes for a Victorian terrace, you will leave with a clear sense of what to budget, what to ask for, and what a fair quote looks like.
How much do new windows cost in the UK in 2026?
As a working benchmark, most UK homeowners in 2026 should expect to pay between £600 and £2,500 fully fitted per standard window, with most replacements landing somewhere in the £800 to £1,500 range. The variation reflects material, style, glazing specification and the condition of the existing opening.
Before comparing prices, it helps to think about the wider finish you want for your home. Brow Windows offers replacement windows for improving warmth, security, and kerb appeal, as well as made-to-measure blinds for light control and privacy, and interior shutters for a more permanent, low-maintenance window dressing. These options are worth considering together if you are planning a full room refresh or want your new windows to work better day to day.
For a whole-house replacement, the realistic budget for a typical UK home is £6,000 to £20,000, depending on the size of the property and the choices made. Here is a snapshot of fitted prices for common configurations:
| Window type | Typical fitted cost (per window) |
| uPVC casement, standard size | £600 – £1,200 |
| uPVC casement, larger or coloured | £900 – £1,800 |
| Aluminium casement | £900 – £2,200 |
| Timber casement | £1,200 – £2,500 |
| Sash window (uPVC) | £1,000 – £1,800 |
| Sash window (timber) | £1,500 – £3,500 |
| Bay window (3 sections) | £2,200 – £4,500 |
| Bay window (5 sections, period style) | £3,500 – £6,500 |
| Tilt-and-turn window | £900 – £1,800 |
| Heritage steel-look aluminium | £1,500 – £2,800 |
London and the South East tend to sit at the upper end of these ranges, while the North, Midlands and Wales typically come in 10 to 15 per cent lower for equivalent specifications. Coastal locations and properties with restricted access add to costs across the board.
Average window costs by material
Material is the single biggest lever on price. It also determines how the windows will look, perform and age, so it is worth understanding what you are actually paying for.
uPVC windows
uPVC remains the most affordable mainstream option and the dominant choice for UK homes. A modern quality uPVC window with multi-chambered profile, double glazing, low-emissivity coatings and warm-edge spacers performs strongly on thermal numbers and lasts 20 to 25 years before hardware and seals start to feel tired. Standard white is cheapest; foiled woodgrain finishes and coloured profiles add £50 to £200 per window. Typical fitted cost: £600 to £1,800 per window.
Aluminium windows
Aluminium has moved firmly into the mainstream over the past decade, particularly on contemporary properties and renovations. The slim sightlines allow for larger glazed panels, finishes are durable, and thermal performance has improved with modern thermal-break construction. Aluminium typically costs 25 to 50 per cent more than uPVC. Heritage steel-look aluminium for period properties sits at the upper end. Typical fitted cost: £900 to £2,800 per window.
Timber windows
Timber is the right answer for period homes, conservation areas and listed buildings, where nothing else looks correct on the elevation. Engineered timber, built up in laminated layers, is far more dimensionally stable than solid hardwood and resists warping. The trade-off is maintenance: timber windows want refinishing every five to seven years, sometimes sooner on south-facing or exposed elevations. Typical fitted cost: £1,200 to £3,500 per window, more for sash configurations.
Composite and timber-alternative windows
Composite windows combine a timber core with an aluminium or GRP outer skin, giving the warmth of timber inside with the durability of aluminium outside. Timber-alternative uPVC products mimic the appearance of painted timber convincingly enough to satisfy some conservation officers and many homeowners. Both are premium products, typically £1,400 to £3,000 per window fitted.
Average window costs by style
Window style affects price almost as much as material, because the configuration changes both manufacturing complexity and installation work.
Casement windows
The most common style on UK homes since the 1980s. A simple side-hung or top-hung casement is the cheapest configuration to manufacture and install, which is why it dominates the new-build market. Casements work on most property types, with traditional proportions for older homes and clean modern proportions for contemporary ones.
Sash windows
Vertical sliding sash windows are the period-correct choice for Victorian, Edwardian and Georgian properties. Modern uPVC and timber sash windows replicate the original proportions and astragal patterns convincingly. Expect to pay 40 to 60 per cent more than a comparable casement, reflecting the more complex mechanism and additional manufacturing.
Bay and bow windows
Bay windows are formed from three or five sections set at angles to project from the elevation. They are visually significant on 1930s semis, Edwardian terraces and any property where the bay is a defining architectural feature. A bay window is essentially several windows combined with structural connectors and weatherproofing details, so the cost is significantly higher than for a single window. Bow windows (curved rather than angled) sit at the upper end of the cost range.
Tilt-and-turn windows
Common on contemporary and continental-style properties, tilt-and-turn windows open inwards either from the bottom (tilt) for ventilation or fully (turn) for access and cleaning. They are slightly more expensive than casements but offer practical advantages on upper floors and properties without external cleaning access.
Fixed and feature windows
Non-opening fixed lights cost less than opening windows because they have no hinges or hardware. They are useful for daylight without ventilation, particularly on staircase landings, gable ends and architectural feature walls. Larger fixed glazed panels for picture windows or large openings cost more due to glass size and handling.
Whole-house replacement examples
Generic per-window prices only get you so far. Here are realistic 2026 fitted budgets for whole-house replacements on the most common UK property types.
One-bedroom flat, four windows
A typical one-bedroom flat with four standard uPVC casement windows lands at £3,500 to £6,000 fitted. Aluminium pushes this to £4,500 to £8,000. The variation depends largely on access (ground floor versus upper floor with restricted scaffolding) and the specification of the existing reveals.
Two-bedroom terraced house, six windows
A typical two-bedroom Victorian or Edwardian terrace with six windows, replacing tired sashes with traditional-style replacements, lands at £8,000 to £15,000 fitted in uPVC sash, £14,000 to £22,000 in timber sash. For listed properties or conservation areas, timber is usually the required material.
Three-bedroom semi, eight to ten windows
A typical 1930s or 1950s semi with eight to ten windows, including a bay window at the front, lands at £6,500 to £12,000 fitted in uPVC casement with a uPVC bay, £10,000 to £18,000 in aluminium, and £14,000 to £25,000 in timber. The bay typically accounts for 25 to 35 per cent of the total cost.
Four-bedroom detached, twelve to fifteen windows
A typical 1990s or 2000s detached home with twelve to fifteen windows, including any bays, dormers or feature windows, lands at £10,000 to £18,000 fitted in uPVC, £15,000 to £28,000 in aluminium, and £20,000 to £40,000 in timber. Larger detached homes with significant glazing, multiple bays or unusual sizes can run higher still.
Period home with sash windows in a conservation area
A typical Victorian or Georgian property in a conservation area, replacing eight original sash windows with new timber sashes to a sympathetic specification, lands at £15,000 to £30,000 fitted, with potential for higher figures on listed buildings or where bespoke profiles are needed. Listed building consent applications and architect or conservation specialist fees can add £1,000 to £3,000 to the project.
What affects the final quote?
Two homeowners can ring the same installer, ask for “new uPVC windows”, and end up with quotes thousands of pounds apart. The difference almost always sits in the detail. Here is what genuinely moves the price.
Size matters more than people realise. Larger windows cost disproportionately more because both the glazing units and the frame profiles scale up in cost and weight. A window that is twice the area of a standard casement typically costs 60 to 80 per cent more, not double, but the increase is real.
Glazing specification has a quiet but significant impact. Standard double glazing with low-emissivity coatings and argon fill is the default. Triple glazing adds 25 to 40 per cent. Acoustic glass for noise reduction adds 10 to 20 per cent. Solar control glass for south-facing rooms or large glazed elevations adds 10 to 25 per cent. For most UK homes, quality double glazing is the right balance.
Colour and finish affect price. Standard white uPVC is the cheapest. Foiled woodgrain finishes (typically Rosewood, Oak, Anthracite Grey, Black) add 10 to 20 per cent. Coloured uPVC profiles add 20 to 30 per cent. Aluminium in standard RAL colours is included in the base price; bespoke RAL matching adds 5 to 15 per cent.
Hardware specification has a quiet but real effect. Basic chrome handles and basic locks are the default; security-rated multipoint locks, anti-snap cylinders on opening windows, and premium brass or pewter handles all add £30 to £150 per window.
Access and scaffolding can transform a quote. Ground-floor windows on a typical home are straightforward. Upper-floor windows usually need a tower scaffold or platform, which adds £400 to £1,500 to a project. Properties with restricted access (terrace with rear-access only, town houses with no driveway, properties on hills or with stairs to the entrance) add further to scaffolding and labour costs.
Frame condition is the biggest single variable that emerges at survey. If the existing frames are sound and square, replacement is straightforward. Rotten timber sub-frames, damaged brick reveals, or sagging lintels all add cost and time. Period properties often reveal these issues only when the existing frame comes out.
Removal, disposal and making good are routinely skimped on cheaper quotes. A complete fitted price should include taking out the old windows, responsible disposal, sealing internally and externally, and finishing the plaster reveals. If a quote is silent on these items, ask explicitly whether they are included.
Double glazing vs triple glazing vs secondary glazing
The glazing specification dominates how the windows perform thermally and acoustically, and it is one of the more confused decisions homeowners face.
Double glazing is the default for UK windows and the right answer for the vast majority of homes. Modern double-glazed units with low-emissivity coatings and warm-edge spacer bars typically achieve glass U-values around 1.1 W/m²K. The whole-window U-value with quality frames lands around 1.2 to 1.6 W/m²K, comfortably within Approved Document L requirements.
Triple glazing reaches lower U-values, typically 0.6 to 0.8 W/m²K on the glass alone and around 1.0 W/m²K on the whole window with quality frames. The improvement is real but marginal compared with quality double glazing, and the cost premium is 25 to 40 per cent. Triple glazing is worth specifying on passive-house projects, properties in extremely exposed locations, or where every fraction of a watt counts. For most UK homes, quality double glazing delivers better value.
Secondary glazing is a separate internal pane fitted inside the existing window. It is the right answer for listed buildings and conservation areas where original windows cannot be replaced, and for properties on busy roads where noise reduction is the priority. Secondary glazing typically costs £200 to £600 per window fitted, far less than full replacement, and can transform the thermal and acoustic performance of period windows without affecting their appearance.
Which windows are best for your home?
The right window choice depends on the property type and what matters most to you. The framework below covers the most common UK situations.
Choose uPVC casements if budget is the priority and the property is a 1960s to 2000s home where uPVC reads as appropriate to the era. Quality uPVC at £700 to £1,200 per window delivers strong thermal performance, low maintenance, and a 20 to 25 year service life.
Choose aluminium if your property is contemporary, you want slim sightlines on larger glazed openings, or you need bespoke RAL colour matching to the rest of the joinery. Aluminium at £1,000 to £2,000 per window suits modern extensions and architect-designed renovations particularly well.
Choose timber sashes if you live in a Victorian, Edwardian or Georgian property, particularly in a conservation area or on a listed building. Timber at £1,800 to £3,500 per window for sash configurations is genuinely the right answer; nothing else looks correct on a period elevation up close.
Choose secondary glazing if your property is listed, in a conservation area with restrictive Article 4 Directions, or on a busy road where noise is a primary concern and replacement is restricted or undesirable. Secondary glazing at £300 to £600 per window preserves the original windows while transforming the thermal and acoustic performance.
Choose a uPVC sash heritage range if your property is period-style but outside conservation restrictions and budget is a real constraint. Modern uPVC sash windows at £1,000 to £1,800 read convincingly enough on most period homes from the pavement.
UK rules: Building Regulations, Part L, FENSA, CERTASS and planning permission
Replacement windows are controlled fittings under the Building Regulations, which means standards apply regardless of who fits them. Understanding the framework protects you from problems when you sell.
Approved Document L of the Building Regulations sets the minimum thermal performance for replacement windows. The current edition incorporates the 2023 amendments and applies to dwellings in England. The limiting whole-window U-value for replacements is 1.6 W/m²K, with a stricter target of 1.4 W/m²K for windows with significant glazed area in some configurations. Most modern compliant windows perform comfortably better than these limits.
Certification is handled by FENSA or CERTASS through registered installers under the Competent Person Scheme. A registered installer self-certifies the work and provides a certificate confirming Building Regulations compliance, usually within four to six weeks of installation. FENSA covers replacement windows, roof windows, roof lights and doors in existing dwellings under 18 metres in height. The certificate is what conveyancers ask for when you sell. Without it, buyers can demand a retrospective Building Control inspection, which is costly and avoidable.
Planning permission is usually not required for like-for-like window replacement on most UK homes. The exceptions are listed buildings (where listed building consent is almost always required) and conservation areas with Article 4 Directions (where permitted development rights for windows may have been removed). On listed properties, Historic England guidance is clear that consent is needed for alterations that affect the building’s character or appearance, which usually includes windows.
Safety glazing rules apply to any window glass at low level. Glass within 800mm of the floor (or 300mm beside a door) must be toughened or laminated safety glass. Most reputable manufacturers fit this as standard, but it is worth confirming on your quote.
Trickle vents (small ventilation openings in the frame) are now required by the Building Regulations on most replacement windows to maintain background ventilation. They are unobtrusive in practice but worth knowing about.
What should a window quote include?
A complete quote should leave you with no surprises on installation day. Before you sign anything, check that the following are explicitly listed.
The technical survey before manufacture. Window-by-window dimensions and specifications. Frame material and profile system. Glazing details including U-values, safety rating (toughened or laminated), and any acoustic or solar control specifications. Window energy rating. Hardware specification including handles, locks, hinges, and trickle vents. Colour and finish on both internal and external faces if different. Removal and responsible disposal of the existing windows. Sealing internally and externally with materials specified. Making good of plaster reveals, sills and surrounding decoration. Scaffolding or access platforms where required. FENSA or CERTASS certification. The manufacturer’s product warranty and the installer’s workmanship warranty, with their separate durations clearly stated.
If a quote is silent on any of these, ask. A good installer will welcome the questions because it tells them you understand the job. A reluctant installer is telling you something useful about how they work.
Common mistakes when budgeting for new windows
Five mistakes appear repeatedly in UK window projects.
The first is treating the cheapest quote as the best value. Window quotes vary widely because what is included varies widely. A £600 per window quote may genuinely cost less than a £900 per window quote, or it may exclude scaffolding, disposal, making-good and certification that the higher quote includes as standard. Compare quotes line by line, not headline by headline.
The second is over-specifying triple glazing. Triple glazing makes sense on specific projects (passive house, exposed locations, large glazed elevations) but adds 25 to 40 per cent to glazing costs without delivering proportionate benefit on most UK homes. Quality double glazing is the right answer for the vast majority of replacements.
The third is assuming all uPVC windows are the same. There is a real difference between cheap uPVC with thin profiles and inadequate steel reinforcement and quality uPVC from a reputable manufacturer with multi-chambered profiles, proper reinforcement and quality hardware. The visual difference is small at first; the long-term performance difference is significant.
The fourth is overlooking listed building or conservation area constraints. Replacing original sash windows on a listed property without listed building consent can result in enforcement action and a requirement to reverse the work at your own cost. Check before you order.
The fifth is buying online without a survey. Online window quotes work for very simple replacements where the openings are perfectly square, the frames are sound, and access is straightforward. For most UK homes, particularly anything pre-1990, an in-person survey is the only way to get an accurate price. Online estimates are useful for budget setting but should never be taken as the final figure.
How to reduce costs without cutting corners
There are sensible ways to reduce a window project budget, and there are false economies that cause problems later. Here is the honest distinction.
Sensible cost reductions: choose standard sizes where possible (bespoke sizes carry a 15 to 30 per cent premium), choose standard white uPVC over coloured profiles where appearance allows, accept casement windows over more complex configurations where the property does not demand them, phase the replacement over two or three years to spread the cost, and combine the project with related work (door replacement, exterior painting) to share access and scaffolding costs.
False economies: cutting hardware specification to save £30 per window (the difference is felt every day), removing FENSA or CERTASS certification (the cost emerges at sale), choosing supply-only with separate fitting (warranties fragment, accountability disappears), accepting a quote without a survey (the gap between quote and reality often more than wipes out the saving), and fitting the cheapest uPVC available (the maintenance and lifespan trade-offs are real).
The best single decision for value is to choose a quality manufacturer in the appropriate material for your property, specify proper hardware and certification, and have the work fitted by a registered installer. Cutting corners on any of these typically costs more in the long run than it saves in the short run.
Frequently asked questions
1. How much does it cost to replace windows in a 3-bed house?
For a typical UK three-bedroom semi with eight to ten windows, expect £6,500 to £12,000 fitted in uPVC, £10,000 to £18,000 in aluminium, and £14,000 to £25,000 in timber. A bay window typically accounts for 25 to 35 per cent of the total cost.
2. What is the cheapest type of replacement window?
Standard white uPVC casement windows are the cheapest mainstream option, typically £600 to £1,200 per window fitted. The cost reflects standardised manufacturing, mature supply chains and the simplest configuration to install.
3. Are aluminium windows worth the extra cost?
For contemporary properties and renovations where slim sightlines and bespoke colour matching matter, yes. Aluminium also lasts longer than uPVC (30 to 40 years versus 20 to 25 years) and holds its appearance better. For traditional homes where aluminium would feel out of place, the premium is harder to justify.
4. Are timber windows worth it for period homes?
Yes, on Victorian, Edwardian, Georgian and listed properties. Timber sash windows are the period-correct material and read correctly on the elevation in a way uPVC and aluminium do not. The maintenance is real (refinishing every five to seven years) but on the right property, the cost premium genuinely earns itself back.
5. Is triple glazing worth it in the UK?
For most UK homes, no. Quality double glazing delivers excellent thermal performance for 25 to 40 per cent less cost. Triple glazing makes sense on passive-house projects, properties in extremely exposed locations, or homes with very large glazed elevations where the cumulative thermal benefit is meaningful.
6. Do I need planning permission to replace windows?
Usually no, on standard freehold houses outside protected areas. Like-for-like replacement is covered by permitted development. Listed buildings require listed building consent. Conservation areas with Article 4 Directions may require planning permission. Flats and leasehold properties often have additional restrictions in the lease.
7. Do I need FENSA or CERTASS certification?
Yes. Replacement windows are controlled fittings under the Building Regulations. A registered FENSA or CERTASS installer self-certifies the work and provides a certificate that conveyancers ask for when you sell. Without it, buyers can demand a retrospective Building Control inspection.
8. Can I replace windows in a conservation area?
Usually yes, but the rules are tighter. Like-for-like replacement is often permitted, but Article 4 Directions in some conservation areas remove permitted development rights for windows. Check with the local planning authority before ordering. The replacement may need to match the original style and material.
9. Can I replace windows in a listed building?
Only with listed building consent. Replacing original windows on a listed property without consent can result in enforcement action. The replacement is usually expected to match the original in material, profile, glazing pattern and operation. Engineered timber or specialist heritage products are typically the only acceptable options.
10. What should a window quote include?
The technical survey, window-by-window specifications, glazing details with U-values and safety rating, hardware specification including trickle vents, colour and finish, removal and disposal, sealing and making good, scaffolding where required, FENSA or CERTASS certification, and clearly stated manufacturer’s and installer’s warranty durations. If a quote is silent on any of these, ask.
11. Why are some window quotes so different?
Quotes vary because the inclusions vary, the manufacturer specifications vary, and the installation standards vary. A cheaper quote may exclude scaffolding, disposal, certification or making-good. A more expensive quote may include premium hardware, certified installation and longer warranties. Compare line by line rather than headline by headline.
12. Can I install windows myself?
Technically yes, practically no for most homeowners. Window installation requires accurate measurement, structural opening checks, weatherproofing, safety glazing compliance and Building Regulations certification. Self-installation forfeits FENSA or CERTASS certification, which means a separate Building Control application and inspection. The saving rarely covers the additional cost and risk.
13. How long does window installation take?
A standard window replacement is typically one to two hours per window for a two-person team, so a whole-house project of eight to twelve windows usually takes one to three days. Properties needing scaffolding, structural work, or bespoke installations can extend to four or five days.
14. Do new windows reduce condensation?
Modern windows with insulated frames and warm-edge spacer bars reduce condensation on the inside surface of the glass and frame because the surface stays closer to room temperature. Persistent condensation in homes after window replacement usually indicates a ventilation issue rather than a window fault, which is part of why trickle vents are now required.
15. Do new windows reduce noise?
Yes, often noticeably. Quality double glazing with proper compression seals reduces external noise by 25 to 30 decibels. Acoustic glass with laminated interlayers adds further noise reduction at modest cost premium and is worth specifying for properties on busy roads or near transport corridors.
16. Should I replace all windows at once or in phases?
Replacing all windows at once delivers consistent appearance, shared scaffolding and access costs, and a single FENSA or CERTASS certificate. Phasing spreads the cost but loses the access savings and may leave the property looking inconsistent during the transition. For most homeowners, a single project is the better value if budget allows.
17. How long do uPVC, aluminium and timber windows last?
uPVC windows typically last 20 to 25 years before hardware and seals start to feel tired. Aluminium windows last 30 to 40 years with quality powder coating. Timber windows last 30 years or more with proper maintenance. Hardware, seals and glazing units may need attention sooner than the frame itself.
18. What are trickle vents and do I need them?
Trickle vents are small ventilation openings in the window frame that maintain background ventilation when the window is closed. They are now required by the Building Regulations on most replacement windows to ensure adequate airflow. They are unobtrusive in practice and contribute to better indoor air quality and reduced condensation.
19. Are cheap double-glazed windows a bad idea?
Cheap windows often cut costs on profile thickness, internal reinforcement, hardware quality and glazing specification. The visual difference at installation is small; the long-term performance difference is significant. Seals fail sooner, hardware feels tired faster, and the warranty is often less reassuring. Buying mid-market quality from a reputable manufacturer typically delivers better long-term value.