Double glazing is one of those jobs where two quotes for the same house can be £4,000 apart, and nothing on either piece of paper explains why. Part of that is genuine — frame material, glass specification and the amount of making-good all cost money. Part of it is sales technique, particularly the discount that only exists today.
This guide sets out what windows actually cost in the UK in 2026, supplied and fitted, and what sits behind the numbers. We fit windows across Central Scotland ourselves, so the figures below are the sort of thing we see day to day rather than a national average scraped off a comparison site.
Typical cost per window, supplied and fitted
Most homeowners buy windows one house at a time, but installers price them per unit. A single opening on a standard semi is usually somewhere between £450 and £900 fitted in white uPVC, and the number climbs with size, the number of opening sashes, colour, and any shaped or leaded detail.
The prices below are supplied and fitted, including removal of the old window, and assume a straightforward ground or first-floor opening with no scaffolding.
| Window type | White uPVC | Coloured / woodgrain uPVC | Aluminium |
|---|---|---|---|
| Small casement (600 x 900mm) | £380 – £520 | £450 – £620 | £650 – £850 |
| Standard casement (1200 x 1200mm) | £520 – £780 | £620 – £900 | £900 – £1,250 |
| Large casement (1800 x 1200mm) | £700 – £1,000 | £820 – £1,180 | £1,150 – £1,600 |
| Tilt and turn | £600 – £950 | £700 – £1,100 | £1,000 – £1,450 |
| Bay window (3 sections) | £1,400 – £2,400 | £1,700 – £2,900 | £2,400 – £3,800 |
| Sash-style uPVC | £800 – £1,300 | £950 – £1,500 | n/a |
Whole-house costs by property type
Doing the whole house at once is almost always cheaper per window than doing two at a time, because the fitting team, the delivery and the waste disposal are all shared across the job. If budget is tight, doing it in two phases is perfectly sensible — just expect to pay a small premium the second time.
| Property | Windows | White uPVC | Coloured uPVC |
|---|---|---|---|
| Flat / 1-bed | 4 – 5 | £2,200 – £3,600 | £2,700 – £4,300 |
| Terraced house | 6 – 8 | £3,400 – £5,600 | £4,000 – £6,600 |
| Semi-detached | 8 – 10 | £4,400 – £7,500 | £5,200 – £8,800 |
| Detached | 10 – 14 | £6,000 – £11,000 | £7,000 – £13,000 |
| Detached with bays | 10 – 14 | £7,500 – £14,000 | £8,800 – £16,000 |
What actually moves the price
Frame material and colour
uPVC remains the value option and, in a good profile system, will outlast most people's plans for the house. Anthracite grey and woodgrain foils typically add 10–20% because the foiled profile costs more and lead times are longer. Aluminium sits roughly 40–60% above uPVC for slimmer sightlines and a crisper look.
Glass specification
Standard A-rated units are the baseline. Toughened or laminated safety glass is required in critical locations — low-level glazing, doors and side panels — and adds cost. Obscure patterns, acoustic laminate for a busy road, and Georgian or leaded detail all add too.
Access and making good
Second-floor openings above a conservatory roof, or anything needing a tower or scaffold, cost more in time than in materials. Old timber frames often hide rotten sub-frames or crumbling lintels, and stone surrounds need careful cutting rather than brute force. A survey that spots this before the order is written is what stops the price changing on fitting day.
Where you can genuinely save money
What is not a saving is a quote that leaves out disposal, internal finishing or trims. That work still has to happen, and it will either appear as an extra later or simply be skipped, which is worse.
- Replace the failed glass unit rather than the whole window if the frame is sound — see our guide to misted double glazing repair costs.
- Stick to white or a single colour across the house rather than mixing foils.
- Keep the same opening configuration; changing where the sashes open means new frames rather than a like-for-like swap.
- Book outside the spring rush if you can be flexible on dates.
- Do the whole property in one visit rather than in dribs and drabs.
How to compare quotes fairly
Ask every installer for the same information in writing: profile system and glass specification, whether the price includes removal and disposal, who does the fitting, how the inside and outside will be finished, and what happens if something needs adjusting in six months.
Be wary of a price that halves while you sit at the kitchen table. A firm that can drop £3,000 on the spot was never charging £3,000 worth of value. Across Central Scotland we quote once, in writing, usually within 48 hours, and the survey price is the price you pay.
Common questions
Per window, yes. Fitting, delivery and waste disposal are shared across the job, so a whole-house order usually works out 10–15% cheaper per opening than doing two at a time.
Want a straight answer on your own windows or doors?
DM Installations fits and repairs windows and doors across Central Scotland — Cumbernauld, Glasgow, Falkirk, Stirling and the surrounding towns. Free survey, written quote, and an honest answer on whether you need a repair or a replacement.
Related guides
Misted Double Glazing Repair Cost
Failed units are usually a glass problem, not a window problem. Here is what replacing the pane costs against replacing the whole thing.
ComparisonsDouble vs Triple Glazing
U-values, realistic payback, noise reduction and the specific situations where triple glazing earns its keep.
When to call a proSigns You Need New Windows
A proper inspection checklist so you can tell a repair job from a replacement job before anyone quotes you.