Aluminium windows cost £400–£600 per window installed in 2026 for a standard casement, rising to £800–£1,200 for larger or more complex configurations. A full-house replacement for a typical 3-bed semi with 10 windows costs £4,000–£8,000 in aluminium, compared to £3,000–£5,000 for uPVC. Aluminium costs 30–60% more than uPVC but offers slimmer frames, longer lifespan, and a modern aesthetic that suits contemporary and heritage properties alike.
We compared pricing from UK aluminium window manufacturers and installers, cross-referencing quotes with trade databases. This guide covers aluminium window costs by size and style, how aluminium compares to uPVC and timber, the slim sightline advantage, powder coating colours, thermal break technology, and what to expect from installation.
The main reason homeowners choose aluminium over uPVC is the frame profile. Aluminium frames are 25–50mm wide compared to 60–70mm for uPVC – this means up to 15% more glass area per window, more natural light, and a cleaner look. Modern thermally broken aluminium also matches uPVC on energy efficiency, eliminating the old cold-frame problem.
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- Standard aluminium window costs £400–£600 installed - 30–60% more than uPVC (£250–£400) but with slimmer frames and longer lifespan
- Full-house replacement costs £4,000–£8,000 - for a 3-bed semi with 10 windows (casement style, standard colours)
- Slim sightlines are the key advantage - 25–50mm frames vs 60–70mm for uPVC, giving up to 15% more glass area
- Lifespan is 40–60 years - double that of uPVC (20–30 years), with virtually zero maintenance
- Powder coating adds 10–20% - RAL colours available; anthracite grey (RAL 7016) is the most popular choice
Aluminium Window Costs at a Glance
Aluminium window prices depend on the window size, opening style, and colour finish. Standard casement windows are the most common and affordable configuration. Tilt-and-turn and fixed windows cost roughly the same, while shaped or arched windows carry a significant premium.
| Window Type | Supply Only | Installed | Notes |
|---|---|---|---|
| Casement (standard) | £200–£350 | £400–£600 | Side-hung or top-hung; most common style |
| Tilt-and-turn | £250–£400 | £450–£650 | Tilts for ventilation, opens fully for cleaning |
| Fixed (picture window) | £150–£300 | £350–£500 | No opening mechanism; cheapest option |
| Bay window (3-section) | £700–£1,200 | £1,550–£2,340 | Angled framework adds cost |
| Shaped / arched | £500–£900 | £750–£1,400 | Bespoke manufacturing; 6–10 week lead time |
Supply-only prices assume standard white or anthracite grey. Labour costs £150–£250 per window for a straightforward like-for-like replacement, or £250–£350 for a first-floor installation requiring scaffolding. London and the South East carry a 15–20% labour premium.
Whole-House Aluminium Window Costs
A full-house aluminium window replacement is a significant investment, but the 40–60 year lifespan means you are unlikely to replace them again. The table below shows project costs for common UK property types.
| Property Type | Windows | Aluminium Cost | uPVC Equivalent |
|---|---|---|---|
| 2-bed flat | 6 | £2,400–£4,200 | £1,500–£2,400 |
| 3-bed semi | 10 | £4,000–£8,000 | £2,500–£4,000 |
| 4-bed detached | 14 | £5,600–£11,200 | £3,500–£5,600 |
| 5-bed detached | 18 | £7,200–£14,400 | £4,500–£7,200 |
Volume discounts of 10–15% are common when replacing all windows in a single order. Lead time from order to installation is typically 4–6 weeks for standard colours and 6–10 weeks for bespoke RAL colours. Get at least three quotes from FENSA or CERTASS-registered installers – prices for the same specification can vary by up to 40%. For a broader cost comparison across all materials, see our complete double glazing cost guide.
Aluminium vs uPVC vs Timber Windows
Aluminium sits between uPVC and timber on price, but its combination of slim frames, durability, and low maintenance makes it a compelling middle ground for many homeowners. The key trade-offs are cost versus appearance versus lifespan.
| Feature | Aluminium | uPVC | Timber |
|---|---|---|---|
| Cost per window (installed) | £400–£600 | £250–£400 | £500–£900 |
| Frame width | 25–50mm | 60–70mm | 55–65mm |
| Lifespan | 40–60 years | 20–30 years | 40–60+ years |
| U-value (typical) | 1.2–1.4 W/m²K | 1.2–1.4 W/m²K | 1.4–1.8 W/m²K |
| Maintenance | Virtually none | Virtually none | Repaint every 3–5 years |
| Appearance | Modern, slim, clean lines | Bulkier, plastic look | Traditional, warm |
| Recyclability | 100% recyclable | Limited recycling | Biodegradable |
| Conservation areas | Often accepted (slim profile) | Frequently refused | Almost always accepted |
The biggest advantage of aluminium over uPVC is the frame profile. A typical aluminium casement frame is 35mm wide – roughly half the width of a uPVC equivalent. This means more glass, more light, and a cleaner appearance both inside and out. The biggest advantage over timber is maintenance: aluminium’s powder-coated finish never needs repainting, while timber requires sanding and repainting every 3–5 years at £200–£500 for a full house.
If cost is your primary concern, uPVC is the better choice. If you want the slimmest frames and longest lifespan with no maintenance, aluminium wins. If your property is listed or you prefer a traditional look, timber remains the standard. For a direct cost comparison on specific window types, see our bay window and sash window cost guides.
Slim Sightlines – Why Aluminium Frames Let in More Light
Slim sightlines are the single biggest selling point of aluminium windows. The frame profile – the visible width of frame between the glass and the wall – is significantly narrower than any other material, which directly increases the amount of natural light entering the room.
How slim is slim? Standard aluminium casement frames are 25–50mm wide, depending on the system. Premium systems like Schüco or AluK achieve sightlines as narrow as 25mm on fixed lights and 45mm on opening casements. By comparison, uPVC frames are 60–70mm and timber frames are 55–65mm. On a standard 1,200mm × 1,200mm window, this difference gives aluminium roughly 12–15% more glass area than uPVC.
Where it matters most. The slim frame advantage is most noticeable on large openings – bifold doors, floor-to-ceiling windows, and french doors. On a 3-metre bifold door set, aluminium frames give you roughly 0.5m² more glass area than the same opening in uPVC. This is why aluminium dominates the premium glazing market for new builds and extensions, where maximising natural light is a design priority.
Powder Coating Colours and Finishes
Aluminium windows are available in any RAL colour – over 200 options – giving far more colour choice than uPVC (which is limited to around 20 foil wraps). The powder coating process electrostatically bonds paint particles to the aluminium, creating a durable finish that resists fading, chipping, and corrosion for 25+ years.
Standard colours (no premium): Most manufacturers include anthracite grey (RAL 7016), black (RAL 9005), and white (RAL 9010) as standard stock colours. These are the most popular choices and are available on the shortest lead times (4–6 weeks).
Non-standard RAL colours add 10–20% to the window price and extend the lead time to 6–10 weeks. Popular choices include slate grey (RAL 7015), signal grey (RAL 7004), and heritage colours like olive green (RAL 6003) and duck egg blue. Marine-grade coating is available for coastal properties at a further 10% premium.
Dual colour – a different colour inside and outside – adds 15–25%. This is popular for matching a dark exterior to the property’s brickwork while keeping a white or light interior to match existing décor. Unlike uPVC dual-colour (which uses applied foil), aluminium dual-colour is a full powder coat on both faces – more durable and more uniform in appearance.
Thermal Break Technology
Aluminium is a highly conductive metal – without thermal insulation, aluminium frames would transfer heat rapidly from inside to outside, causing condensation and poor energy performance. Thermal break technology solves this by inserting a low-conductivity barrier (typically polyamide) between the inner and outer aluminium sections of the frame.
Modern thermally broken aluminium windows achieve a whole-window U-value of 1.2–1.4 W/m²K with standard double glazing – identical to uPVC and meeting current Building Regulations (Part L). With triple glazing and enhanced thermal breaks, U-values can drop to 0.8–1.0 W/m²K. The thermal break also eliminates the cold-to-touch frame problem that plagued older aluminium windows – modern frames feel warm to the touch even in winter.
If you are comparing quotes, check that the window system uses a polyamide thermal break (not PVC or foam, which are cheaper but less effective). The width of the thermal break matters: 20mm+ is standard on quality systems, while budget systems may use a 12–15mm break that achieves a slightly worse U-value. For energy efficient window options and available grants, see our dedicated guides.
Lifespan and Maintenance
Aluminium windows last 40–60 years – roughly double the lifespan of uPVC (20–30 years) and comparable to hardwood timber (40–60+ years). The powder-coated finish never needs repainting, and aluminium does not rot, warp, swell, or discolour over time.
Maintenance requirements: Clean frames with warm soapy water every 6–12 months. Lubricate hinges and locking mechanisms with silicone spray or PTFE lubricant annually. Check and replace rubber gaskets and seals every 15–20 years (£50–£100 per window). That is the full extent of maintenance – there is no painting, staining, or treating required at any point in the window’s lifetime.
Cost per year of ownership: An aluminium window at £500 lasting 50 years costs £10/year. A uPVC window at £300 lasting 25 years costs £12/year. A timber window at £700 lasting 50 years costs £14/year plus £40–£80/year in maintenance (painting, staining). On a whole-life cost basis, aluminium is comparable to uPVC and significantly cheaper than timber. For repair options on existing windows, see our repairs guide.
Planning Permission and Conservation Areas
Replacing existing windows like-for-like does not normally require planning permission under permitted development rights. However, aluminium windows are increasingly specified for conservation areas where uPVC is refused, because their slim frame profiles closely replicate the sightlines of original steel or timber windows.
Conservation areas: Many conservation officers now accept aluminium as an alternative to timber, provided the frame profile matches the original windows. Slim-profile aluminium systems (25–35mm sightlines) are particularly well-suited for replacing original steel-framed windows from the 1920s–1950s. Check with your local planning authority before ordering – requirements vary between councils.
Listed buildings: Listed Building Consent is required for any window changes. Timber remains the default expectation for most listed buildings, but aluminium is occasionally accepted for 20th-century listed buildings where the original windows were steel-framed. The consent application is free but takes 8–12 weeks.
All replacement windows must comply with Building Regulations regardless of planning status. Part L (energy) requires a minimum whole-window U-value of 1.4 W/m²K, and Part N (safety) requires toughened glass below 800mm from floor level. A FENSA or CERTASS-registered installer can self-certify compliance, saving you the cost and delay of a separate Building Control application.
Use our free cost estimator for an instant price estimate, or see our best window companies for vetted national installers.
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