London · 2026
uPVC Windows in
London.
Why uPVC is still the right answer for most London houses
Most window replacement in London is not an architectural project. It is a Victorian terrace or an interwar semi with tired frames, draughts, and a heating bill that goes out of the glass. For that job uPVC does everything that matters: it hits A+ energy ratings, it meets PAS 24 security, it does not rot or need repainting, and it costs roughly half what the equivalent aluminium window costs.
Where uPVC runs out of road is size and sightline. It is not a structural material, so the profile needs bulk to stay rigid, which caps how big a single sash can be and how thin the visible frame can look. If you want a 3-metre fixed pane, a corner with no post, or a genuine steel-look profile on a principal elevation, you need aluminium and we will say so. For a standard opening on a standard house, specifying aluminium is spending money on something nobody will notice.
The other thing worth being blunt about: the difference between a good uPVC window and a bad one is not the plastic. It is the sealed unit, the reinforcement, the hardware, the fitting and the sealing. A cheap window is cheap in the parts you cannot see.
The uPVC window range we fit
Seven window types on one platform, manufactured in the UK to your surveyed openings. Whole-window U-values and acoustic figures are the system's own tested data.
| Window type | Best for | U-value from | Acoustic | Max sash width |
|---|---|---|---|---|
| Casement | The standard outward-opening window, most rooms, most houses | 1.2 W/m²K | 42 dB | 1200mm |
| Flush casement | Sash sitting flush in the frame, closest to a timber casement | 1.2 W/m²K | 40 dB | 1100mm |
| Sliding sash | Victorian and Edwardian vertical sliders, tilt-in for cleaning | 1.2 W/m²K | 41 dB | 1500mm |
| Bay & bow | Front-elevation bays, three, four and five-piece runs | 1.2 W/m²K | 42 dB | 3600mm |
| French casement | Pairs opening as a single unobstructed aperture, no centre mullion | 1.2 W/m²K | 40 dB | 1800mm |
| Tilt & turn | Inward-opening, ventilate on tilt, best thermal figure in the range | 0.93 W/m²K | 37 dB | 1200mm |
| Heritage profile | Period detailing, glazing bars, deeper sightlines | 1.3 W/m²K | 41 dB | 1100mm |
uPVC window prices by type
Indicative fitted prices per window for London, including VAT, frame, sealed units, fitting, removal and disposal of the old window, and FENSA self-certification. Structural work such as lintels or cill replacement is quoted separately.
| Window type | From | To |
|---|---|---|
| Casement | £550 | £1,200 |
| Flush casement | £650 | £1,400 |
| Tilt & turn | £700 | £1,500 |
| French casement | £750 | £1,600 |
| Heritage profile | £800 | £1,700 |
| Sliding sash | £900 | £1,800 |
| Bay or bow | £1,800 | £4,500 |
Size, glass specification, colour and access move these figures. Triple glazing, acoustic laminated units and dual-colour woodgrain finishes sit above the ranges shown. For whole-house numbers see the cost of new windows in London, or sash window costs if you are replacing vertical sliders.
Standard specification
What every uPVC window we fit includes as standard, and what can be upgraded. We do not offer a stripped-down entry specification, because the parts people strip out are the parts that fail.
| Property | Standard | Upgrade |
|---|---|---|
| Profile | 70mm chamfered or flush, multi-chamber | Period profile with glazing bars |
| Reinforcement | Steel-reinforced sashes | n/a |
| Glazing | 28mm double glazed, 4-20-4 | 36mm triple glazed |
| Cavity | 90% argon fill, soft-coat Low-E, warm-edge spacer | Acoustic laminated, solar control, obscured |
| Energy rating | A+ available | A++ with triple glazing |
| Security | Multi-point locking, internal beading | PAS 24 certified specification |
| Colours | 20 colourways held in stock | 30 across the woodgrain collection, dual colour |
| Guarantee | 10-year manufacturing guarantee | 12-month workmanship guarantee on the installation |
| Material | 100% recyclable PVC-U | n/a |
What "A-rated" actually means, and what the regulations require
Window Energy Rating is a whole-window scale that combines heat loss, solar gain and air leakage into a single band from A++ down to E. It is a useful shorthand, but the number that regulations and building control actually work to is the U-value.
| Requirement | Standard |
|---|---|
| Maximum U-value on a replacement window | 1.4 W/m²K, or Window Energy Rating Band B minimum |
| No downgrade | The new window must also be no worse than the one it replaces |
| Background ventilation, habitable rooms and kitchens | Minimum 8,000mm² equivalent area |
| Background ventilation, bathrooms | Minimum 4,000mm² equivalent area |
| Existing trickle vents | If the old windows had them, the new ones must too, no smaller and controllable |
| Heritage exception where character must be maintained | Centre-pane U-value no worse than 1.2 W/m²K, or low-E secondary glazing |
Those requirements come from Approved Document L Volume 1, 2021 edition (Table 4.2, paragraphs 4.8 and 4.10) and Approved Document F Volume 1, 2021 edition (paragraphs 3.14 and 3.15). Every uPVC window on this page clears the 1.4 W/m²K threshold at its standard specification. Apex Glazing is FENSA-registered (Reg 40373), so compliance is self-certified and notified to your local authority, and you receive a FENSA certificate for the property file. Our guide to window U-values explains what the figures mean in practice.
Period properties and conservation areas
The honest position, because a lot of what is written about this is wrong. Being in a conservation area does not, by itself, mean you need planning permission to replace windows on a house. What removes that right is an Article 4 Direction covering windows and doors at your specific address, and most conservation areas do not have one. Listed buildings are a separate matter and always need Listed Building Consent. Check your own address on the national Planning Data service and confirm with your borough; our planning permission guide walks through it.
Where an Article 4 Direction does apply, or where you simply want the house to look right, the questions a conservation officer asks are always the same ones. What is the sightline, how deep is the frame, is the opening method the same as the original, where do the glazing bars sit and are they through-bars or stuck-on, does a sash window still read as a sash, and what colour is it. Those are specification decisions, not material decisions, and they are the reason a period-profile uPVC window can be acceptable where a standard chamfered casement is not.
On a principal elevation of a house whose original windows were timber sashes, a uPVC sliding sash with correct proportions is the strongest uPVC case you can make. Where the originals were steel, uPVC will not convince anyone and steel-look aluminium is the right answer. Where replacement is refused outright, secondary glazing is the compliance route the Building Regulations themselves point to.
We do not publish a list of which London conservation areas will or will not accept uPVC. Those decisions sit with individual case officers against individual appraisals and change over time, and guessing at them in print is how homeowners end up ordering windows they cannot install.
uPVC or aluminium?
| Factor | uPVC | Aluminium |
|---|---|---|
| Typical fitted price per window | £550-£1,800 | £900-£3,000+ |
| Best U-value we fit | From 0.93 W/m²K | From 0.84 W/m²K |
| Visible frame | 70mm profile | Slimmer visible section for the same opening |
| Largest single pane | Limited by profile rigidity | Fixed panes to 4m and 500kg of glass |
| Structural corner, no post | Not possible | Yes |
| Steel-look period profile | Approximation only | 59mm sightlines |
| Finish | Foils and woodgrains, 30 colourways | Powder coat, any RAL, dual colour |
| Best for | Casement, sash, bay, budget and volume replacement | Slim sightlines, large spans, corners, steel-look |
The same trade-off applies to doors. A uPVC sliding patio door carries an interlock of 100mm or more because the material needs bulk, so if the sightline is the point you are looking at slimline aluminium sliding doors instead. The longer write-up is on our uPVC vs aluminium page.
Frequently asked
How much do uPVC windows cost in London?
As an indicative fitted range including VAT and FENSA certification: casement £550 to £1,200, flush casement £650 to £1,400, tilt and turn £700 to £1,500, French casement £750 to £1,600, period profile £800 to £1,700, sliding sash £900 to £1,800, and bay or bow windows £1,800 to £4,500. Size, glass specification, colour and access all move the figure, so a surveyed quote is the only real number.
What U-value do uPVC windows achieve?
Across the range we fit, whole-window U-values start at 0.93 W/m²K on the tilt and turn, 1.2 W/m²K on casement, flush, sash, bay and French windows, and 1.3 W/m²K on the period profile. Building Regulations require a maximum of 1.4 W/m²K, or Window Energy Rating Band B, for a replacement window in an existing dwelling, so every option clears the standard on its base specification.
Are uPVC windows secure?
Yes. Steel-reinforced sashes, multi-point locking and internal beading are standard, and a PAS 24 certified specification is available across the range. Internal beading matters more than people realise: it means the glass cannot be removed from outside. If your insurer or a Secured by Design requirement specifies something particular, tell us at survey and we will specify to it.
Can I get uPVC windows in colours other than white?
Yes. Twenty colourways are held in stock and thirty are available across the woodgrain collection, in smooth, grained and woodgrain foils that never need repainting. Anthracite grey, black, cream and oak-effect finishes are the most commonly specified in London. Dual colour lets you run a different finish inside and out, typically white internally with a darker exterior.
Do I need planning permission for uPVC windows?
Usually not. On a house that is not listed and not covered by an Article 4 Direction, replacing windows in the same openings with units of similar appearance is not development and needs no application. An Article 4 Direction covering windows does require householder planning permission, listed buildings always require Listed Building Consent, and flats have no householder permitted development rights at all. Check your address on planning.data.gov.uk and with your borough.
Can uPVC windows be used in a conservation area?
Sometimes, and it depends on the elevation and the officer rather than on a blanket rule. Like-for-like replacement of existing uPVC is generally straightforward. Replacing original timber sashes with standard uPVC on a principal elevation is often resisted, whereas a period-profile sliding sash with correct proportions and through glazing bars has a much better chance. Where the original windows were steel, uPVC is the wrong material and steel-look aluminium is the answer.
How long do uPVC windows last?
Modern uPVC frames are UV-stable and designed for decades of service with essentially no maintenance beyond washing and occasional hinge lubrication. The component with the shorter life is the sealed unit, which will eventually lose its cavity gas and can mist internally; ours carry a 10-year manufacturing guarantee covering the frame, glass seal and hardware. A failed sealed unit can normally be replaced without replacing the frame.
Are uPVC windows recyclable?
Yes. The PVC-U profile is 100% recyclable, and the frames we remove go to a licensed waste facility rather than to landfill by default. Removal, disposal, making good of internal and external reveals and a final clean-up are included in the quoted price, with no extras for skip hire or waste removal.
Where are your uPVC windows made?
Manufactured in the UK, to the openings we measure on site rather than to stock sizes. That matters on London housing stock, where almost nothing is square and openings within the same terrace vary by tens of millimetres. Made-to-measure is also what allows a period profile to sit correctly in a reveal instead of being packed out.
How long does a uPVC window installation take?
Most installations are completed in one to two days. Sliding sash windows take longer per opening because of the box detailing, and full-house replacements typically run three to seven days. Bay windows need care because the structure above often bears on the window itself, so they are surveyed and propped properly rather than rushed. You get a precise schedule at survey stage.
Does using a FENSA-registered installer cost more?
No. FENSA registration is a competent person scheme that lets us self-certify the installation against the Building Regulations and notify your local authority directly, instead of you paying for a separate building control application and inspection. You receive a FENSA certificate afterwards, which is the document a buyer's solicitor asks for when you sell. Apex Glazing is Reg 40373.
uPVC or aluminium doors, which should I choose?
For a standard back door or French doors on a modest opening, uPVC is entirely adequate and cheaper. For sliding patio doors the answer is almost always aluminium, because a uPVC slider carries an interlock of 100mm or more and cannot approach the panel sizes aluminium manages. For bifolds, aluminium again, because the panels have to stay rigid and true across many hinges.
Where we fit uPVC windows across London
We survey, supply and install with our own teams across west, south-west and central London and into Surrey, including Richmond, Twickenham, Kingston, Hounslow, Ealing, Chiswick, Putney, Wimbledon, Fulham, Hammersmith, Surbiton, Teddington, New Malden and Esher. The full list is on areas we cover.
Related: double glazing specifications, aluminium windows, double versus triple glazing and planning permission for new windows.
