How much does double glazing cost in the UK?
Double glazing costs £400 to £900 per window in the UK, typically around £550. What moves the price most is number and size of windows, so a simpler job sits near the bottom of that range and a larger or higher-spec one near the top. Prices reviewed June 2026.
Double glazing is priced per window, so the number and size of windows is the main factor, then frame material and glass spec.
Double glazing cost calculator
Use the calculator to price your double glazing in 2026. Adjust the options and area for a UK cost range. Nothing is sent anywhere.
To price the whole job, use the double glazing cost calculator.
Double glazing cost breakdown
Typical double glazing costs, by the unit:
| What | Typical UK cost |
|---|---|
| Per window, supplied and fitted | £400 to £700 per window |
| + Aluminium frames | add £150 to £350 per window |
| 5 windows | £2,000 to £3,500 |
| 9 windows (typical) | £3,600 to £6,300 |
| 18 windows | £7,200 to £12,600 |
What's included in the price?
Typical double glazing prices include:
- The window unit and frame
- Removal of the old window and fitting
- Trims, sealing and certification
- Standard A-rated glass
What changes the price?
The things that move double glazing prices most:
Number and size of windows
Frame material: uPVC is cheapest, then aluminium, then timber
Style: casement is cheapest, sash and shaped windows cost more
Glass spec and any colour or finish
How the price is built up
The figure on your quote covers the made to measure frame and sealed glass unit, the fitter's time to remove the old window and install the new one, and the trims, sealant and certification that finish the job. A standard white uPVC casement sits near the bottom of the band, from about £400 per window, with £550 being a fair typical figure once you account for average sizes and a reasonable glass spec. Larger openings, coloured or woodgrain finishes, sash mechanisms and upgraded glass push a window towards £900 or beyond, and access work such as scaffolding for upper floors is usually added on top. On a typical fitted window the frame and glass unit make up the larger share, with labour usually working out at roughly a third to two fifths of the per window price.
Ways to keep the cost down
- Get three quotes from local installers rather than national brands; the same window is often hundreds cheaper per opening once you strip out heavy advertising and commission.
- Order all windows in one visit so the fitting team only mobilises once, which spreads the fixed call out and setup time across the whole job.
- Stick to standard white uPVC casements where you can; coloured, woodgrain and sash options are a genuine upgrade in cost, not a small add on.
- Be wary of large 'today only' discounts off an inflated starting price, and check the firm registers your installation with FENSA or CERTASS so you are not paying separately for building control.
Does where you live change the cost?
In London, double glazing typically costs around £660 per window, about 20% above the UK average of £550. In the North, Scotland and Wales the guide figure is nearer £530.
| Region | From | Typical | Up to |
|---|---|---|---|
| Midlands / East (UK average) | £400 | £550 | £900 |
| London | £480 | £660 | £1,100 |
| South East / South West | £420 | £580 | £950 |
| North / Scotland / Wales | £390 | £530 | £870 |
Guide prices per window, scaled with the same regional multipliers as the calculator. Not quotes.
Double glazing cost in major UK cities
| City | From | Typical | Up to |
|---|---|---|---|
| Belfast | £380 | £520 | £860 |
| Birmingham | £400 | £550 | £900 |
| Bristol | £420 | £580 | £950 |
| Cardiff | £390 | £530 | £870 |
| Edinburgh | £390 | £530 | £870 |
| Glasgow | £390 | £530 | £870 |
| Leeds | £390 | £530 | £870 |
| Liverpool | £390 | £530 | £870 |
| London | £480 | £660 | £1,100 |
| Manchester | £390 | £530 | £870 |
| Newcastle | £390 | £530 | £870 |
| Sheffield | £390 | £530 | £870 |
City guide estimates, scaled by local labour costs. Indicative averages for double glazing, not quotes.
The gap is in the fitting. The units themselves cost much the same everywhere.
Compare this with a real quote
The figures above are guide prices. Two or three quotes for your double glazing tell you what it costs where you live.
Common questions
How much to double glaze a whole house?
A typical three bedroom house with around 8 to 10 windows costs roughly £4,500 to £7,500 in uPVC. Aluminium or timber pushes this higher.
Which window frames are cheapest?
uPVC casement windows are the cheapest. Aluminium costs more but is slimmer and stronger, and timber is the most expensive and needs maintenance.
How long does double glazing last before it needs replacing?
Double glazing typically lasts around 20 to 35 years before the units need replacing, though the frames often outlast the sealed glass. The first sign of wear is usually misting or condensation between the panes, which means the seal has failed on that unit. Replacing the glass unit alone is far cheaper than a full window, but once several units fail across a house it can be more sensible to budget for new windows at roughly £400 to £900 each rather than patching them one by one.
Does double glazing add value to a house?
Double glazing rarely pays for itself pound for pound, but tired or single glazed windows can put buyers off and drag down offers, so replacing them removes a negative rather than adding a clear premium. At a typical £550 per window, a full set on a three bed semi runs into several thousand pounds. The bigger day to day return is lower heating bills, less draught and reduced outside noise, which matter more to most owners than any headline uplift in valuation.
How long does it take to fit double glazing in a house?
Most installers fit a single window in a couple of hours, so a full three bed house of around eight to ten windows is commonly done in one to three days by a two person team. Sash windows, awkward access or bay windows take longer. This is already built into the per window price within the £400 to £900 band, so a faster job does not usually mean a cheaper one; you are paying for the window and a competent fit, not the hours alone.
How much does it cost to double glaze a 3 bed semi?
A 3 bed semi usually has around 8 to 10 windows, so at roughly £400 to £900 per window the whole job tends to fall between about £3,200 and £9,000 fitted. A typical uPVC casement job sits near the lower half of that range. Aluminium or timber frames, bay windows and awkward upstairs access push the total higher, so measure your own window count before assuming a figure.
Is it worth replacing 25 year old double glazing?
Double glazing that is 25 years old is often worth replacing if seals have failed, units have misted, or frames have warped, since older units insulate less well than modern coated, argon-filled glass. Full replacement runs from about £400 to £900 per window fitted. If the frames are still sound, replacing just the misted sealed units costs far less, so it is worth pricing both options before committing.
How much should 10 new uPVC windows cost?
Ten standard white uPVC casement windows typically cost £4,000 to £7,000 supplied and fitted, which is £400 to £700 per window. Larger openings, bays and sash styles push the per-window price up, and aluminium frames add roughly £150 to £350 each. If quotes come in far above this for ordinary casements, get more quotes: the spread between firms on identical specs is one of the widest of any home improvement.
Do new double glazed windows actually save energy?
Yes, but the saving is smaller than most sales pitches imply and it depends entirely on what you are replacing. Going from single glazing to modern double glazing makes a real difference to heat loss, draughts and how warm a room feels near the window. Going from 15-year-old double glazing to new double glazing is a much smaller step, because the big gain was made the first time. At £400 to £900 a window, a whole-house job runs into several thousand pounds, so treat the energy saving as one benefit among several rather than a payback calculation that stands on its own. The stronger reasons to replace are usually failed seals, misted units and draughts.
Do replacement windows need trickle vents?
In England, usually yes, and it is the most common thing missing from a quote. Approved Document F changed on 15 June 2022, and replacement windows in a habitable room now generally need background ventilation of 8,000mm² equivalent area, normally provided by trickle vents in the frame. That applies even where the old windows had none, which is the part that surprises people. The exception is replacing only the sealed glass unit inside an existing frame, which does not trigger it. Ask whether trickle vents are included before you compare prices, because a quote without them is both cheaper and not compliant, and a FENSA or CERTASS installer has to self-certify the work against the current regulations.
Can I fit double glazing myself?
You can fit replacement units yourself and save on labour, which is only about a third to two fifths of the per-window price, so the saving is smaller than on many jobs. The bigger issues are getting each frame square, sealed and weathertight, and that replacements must be building control compliant, usually through a FENSA-registered fitter who self-certifies. A poor seal causes draughts and misting, so most homeowners let an installer handle the whole window.
Check they are registered before they start
Replacement windows and doors have to comply with the building regulations. A fitter in an authorised scheme certifies their own work and gives you the certificate; without one you need a building control application. Checking takes about a minute and it is free.
- Find a FENSA approved installer FENSA · FENSA is one of the authorised schemes for replacement windows and doors, not the only one, so a fitter registered with Certass or another scheme can certify the work just as well
Cite this data
These figures are free to use in articles, reports and research under a CC BY 4.0 licence. All we ask is a credit to Costwise, and online a link. Where your style allows, please make "Costwise" the linked word so readers can check the figure for their own region.
Costwise (2026): Double glazing typically costs £550 in the UK, ranging from £400 to £900 per window. Reviewed June 2026. costwiseuk.co.ukSource: Costwise (costwiseuk.co.uk)Costwise (2026). Double glazing cost. Costwise UK cost data, version 2026-09-28. https://costwiseuk.co.uk/double-glazing-cost/2026-09-28 (156 jobs)Dataset DOI: 10.5281/zenodo.21159943 · also on Kaggle, Hugging Face and Figshare. Method: how we price. Downloadable CSV.
These are independent guide prices based on typical UK jobs in 2026. Your actual cost depends on your property, spec, access and where you live. Always get at least three written quotes before committing.