Cost calculator
New windows cost calculator
Window quotations are the classic example of a headline discount hiding a specification difference. Frame material, glass unit, hardware and how the opening is made good afterwards decide whether two prices are actually comparable.
Count each opening separately, including small ones.
Broad trade availability keeps day rates near the national average.
Estimated range, ex VAT
£4,600 – £12,500
- Labour (typical)
- £2,550
- Materials (typical)
- £5,900
Guidance only. A real quotation depends on site conditions, specification and access — which is exactly what an independent review of your own quote will tell you.
What affects the cost
Frame material
uPVC is cheapest, aluminium 40–70% more, timber and aluminium-clad timber higher again with maintenance implications.
Glazing specification
Standard double glazing, low-E coatings, acoustic laminate, obscure and triple glazing all sit at different price points.
Opening size and style
Bays, sashes and arched heads cost far more than a standard casement of the same area.
Making good
Plaster reveals, external sealant and sill replacement are separate work items that some installers exclude.
Conservation constraints
Listed buildings and conservation areas may require timber sashes or slim-profile heritage units.
Regional pricing differences
Materials cost roughly the same everywhere in the UK; labour does not. Use the region selector above to apply a local index — London and the South East typically run 15–30% above the national average, while the North East, Northern Ireland and Yorkshire sit below it.
Labour vs materials
Roughly 30% of this type of work is labour and 70% materials. Frames and glazing units are the bulk of the cost. Fitting is typically £120–£220 per window plus making good.
Common hidden costs
- Trickle vents, now required on most replacements — sometimes added after order.
- Structural lintel repairs discovered when the old frame is removed.
- Scaffolding for upper floors on three-storey or awkward-access properties.
- FENSA or Certass certificate registration, which you will need at resale.
How to save money
- Do the whole house at once — mobilisation and fitting rates improve significantly on volume.
- Ignore 'today only' discounts. Take three written quotes on identical specification and compare the U-value, not the sticker.
- Standard casement sizes cost far less than bespoke shapes.
- Check whether the quote includes removal and disposal of the old frames.
Frequently asked questions
How much do new windows cost for a 3 bed house?
Typically £5,500–£11,000 for uPVC across 8–10 windows, and £9,000–£18,000 in aluminium.
How long do replacement windows take to fit?
Most houses are done in one to three days once the units are manufactured, which takes 4–8 weeks.
Is triple glazing worth it?
Marginal on energy for most UK homes, but noticeably better for noise. Spend on good installation and airtightness first.
What certification should I get?
A FENSA or Certass certificate, or a building control completion certificate if the installer is not registered.
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Private
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