Expect to pay between £550 and £950 per window fitted, with most homeowners settling around £650 for a standard uPVC casement. A typical three-bed semi with eight to ten windows usually lands between £5,500 and £7,500 for a full uPVC replacement. Replacement earns its keep fastest when units are misted, draughty or original single glazing; if your existing double glazing still works well, the energy savings alone rarely justify an early swap.
TL;DR:
- The cost of replacing a full house with uPVC windows typically ranges from £5,500 to £7,500, depending on size and location.
- Glass upgrades such as triple glazing, low-E coatings, and acoustic panels can add £50 to £150 per window, significantly increasing total costs.
- Labour, removal, and extras like scaffolding or structural repairs can account for up to half of the final price, so detailed quotes are essential.
- Pricing varies by region, with London and the South East costing 10 to 30 percent more than northern areas for identical specifications.
- Prioritize getting itemized quotes that specify glass U-value and verify installer certification before making a decision.
Table of Contents
- Double glazing cost at a glance
- What actually moves the price of your windows
- Installation costs and the extras that catch people out
- Worked whole-house examples for budgeting
- Building regulations and certification you need to check
- How to get accurate quotes and spot red flags
- Timescales and disruption during installation
- Our approach to windows and glazing across the North West
- What actually matters when you’re comparing quotes
- Get a fixed-price survey from a local, accredited team
- Sources
Double glazing cost at a glance
Frame material is the biggest single variable in any quote. uPVC remains the cheapest option and the benchmark most homeowners compare against; timber and composite frames sit well above it, and aluminium falls somewhere in the middle depending on the finish.
- uPVC casement: typically £550–£950 per window, around £550 on average
- Aluminium: typically £750–£1,200 per window
- Timber or composite: typically £800–£1,450 per window, often more for bespoke joinery
For a rough whole-house guide: a one-bed flat with several windows might cost a few thousand pounds; a two-bed terrace with several windows more; a four-bed detached with over a dozen windows could reach higher amounts. A typical three-bedroom house replacement with standard uPVC units commonly comes to £5,500–£7,500. Location matters too. Homeowners in London and the South East typically pay 10 to 30% more than those in the North West for identical specifications, which is one reason a Warrington or Wigan quote often looks better value than the same job priced in the capital.
What actually moves the price of your windows
Material is only part of the story. Glass specification adds up fast: low-E coatings, argon gas fills, acoustic laminated glass and triple glazing each push the per-window price higher, sometimes by £50 to £150 depending on the combination.
Window style matters just as much. A standard casement is the cheapest shape to manufacture and fit. Sash windows, bay windows and anything bespoke, curved or heritage-style require more joinery time and specialist fitting, which shows up directly in labour costs.
- Frame material: uPVC cheapest, aluminium mid-range, timber/composite priced highest
- Glass upgrades: triple glazing and acoustic laminated panels add noticeably to unit cost
- Style: bay and sash windows cost more than casements due to complexity and fitting time
Pro Tip: Ask every installer to quote the glass U-value, not just “double glazing” as a term. A lower U-value means better insulation, and comparing that single figure across quotes tells you far more than comparing headline prices alone.
Installation costs and the extras that catch people out
Labour and removal typically account for around 30–50% of the fitted price, so a quote that looks unusually cheap may be skimping here. Scaffolding for upper floors or awkward access adds £300–£1,200 depending on height and duration.
- Skip hire for old frame disposal: usually £150–£350
- Plastering and making good around new frames: £100–£300 per window
- Structural repairs to rotten lintels or sills: variable, but worth asking about upfront
Worked whole-house examples for budgeting
Real budgets depend on glazing area and window mix more than bedroom count alone, but these examples give a sensible starting point.
- Two-bed terrace, six standard uPVC casements: roughly £3,000–£5,700 fully fitted
- Three-bed semi, eight to ten uPVC casements: roughly £5,500–£7,500, the most commonly quoted UK benchmark
- Four-bed detached, twelve to fourteen mixed windows including one bay: roughly £7,000–£13,000, with the bay alone often adding £1,500–£2,500 over a standard casement
- Heritage or bespoke timber sash replacements: can push individual windows to £1,000–£1,800 each, so a full house easily exceeds £10,000
Building regulations and certification you need to check
Replacing windows and doors can require building-regulations approval, though most homeowners avoid the local authority route by using a FENSA or Certass registered installer, who self-certifies compliance instead.
- Ask for FENSA or Certass registration before signing anything
- Confirm the installer understands current thermal performance targets under Approved Document L (2026)
- Keep your compliance certificate; it matters for resale and warranty claims
How to get accurate quotes and spot red flags
A proper quote itemises frame material, glass U-value, finish, labour and every extra separately, not as one bundled figure. Compare quotes line by line rather than by the bottom number alone, since a lower total sometimes hides a lower spec.
- Missing FENSA or Certass registration
- Vague scope with no glass spec or U-value stated
- Large upfront deposits before any work has started
- Unrealistically fast lead times with no survey mentioned
Pro Tip: If two quotes for the “same” job differ by more than 20%, ask both installers to confirm the exact glass specification. Nine times out of ten, that’s where the gap comes from.
Timescales and disruption during installation
Most standard windows take 30–60 minutes each to fit; a typical house takes one to three days. Sash, bay and heritage jobs run longer and may need scaffold. Clear access, protect nearby furniture, and agree working hours in advance.
Our approach to windows and glazing across the North West
With over 35 years managing projects end to end, we deliver fixed-price, fully itemised quotes across Warrington, St Helens, Wigan and nearby towns, backed by hundreds of completed local jobs and handled building-regs paperwork.
What actually matters when you’re comparing quotes
Most guides fixate on the headline per-window price, and that’s the wrong place to start. The number that actually predicts whether you’ll be happy in a year is the glass U-value and the quality of the fit, not the total on page one of a quote.
Here’s where conventional advice falls short: it treats “double glazing” as one product, when in practice you’re buying two separate things, a frame and a glazing unit, and either can be compromised to hit a lower price. A cheap frame with excellent glass will still draught. Good glass in a poorly fitted frame will still condensate at the edges within two winters.
If you’re weighing up whether to replace at all, prioritise condition over age. Misted units and failed seals justify replacement on comfort grounds alone, whatever the energy-bill maths says. Working double glazing that’s merely “a bit dated” is a lower priority, and the payback on upgrading it purely for efficiency is often slower than homeowners expect.
What should you do differently? Get two or three itemised quotes, insist on seeing the U-value in writing, and check FENSA or Certass registration before you check the price. The order you do those three things in matters more than most people realise.
— Gareth
Get a fixed-price survey from a local, accredited team
Complete-Property-Solutions is the practical alternative to piecing together quotes from strangers and hoping the cheapest one holds up. Every survey we carry out results in a fixed-price quotation covering the full specification, glass U-value, finish, labour, FENSA or Certass certification assistance, and making good after fitting, so there are no surprise extras once work starts.
New A-Rated Windows and Door installed in Penketh.
We cover Warrington, St Helens, Wigan, Great Sankey, Penketh, Culcheth, Lowton, Rainhill and Haydock, with most straightforward jobs surveyed within a week or two and installed shortly after. If you’re weighing up windows alongside a larger renovation, our guide to home extensions that add value is worth a look before you commit to either project separately.
To book a survey, get in touch with a few photos of your current windows and rough measurements to hand. It helps us give you a more accurate initial estimate before we visit, and you’ll come away with a proper written quote, not a verbal guess.
Sources
Pricing and compliance figures come from Approved Document L, GOV.UK building-regulations guidance, and industry price surveys including Aluglaze and wider home energy efficiency guidance.
