Old uPVC windows are good at hiding what they cost. They still open, they still close, they still keep the rain out, so they feel like they're free. They aren't. Greater Manchester has hundreds of thousands of windows left over from the double-glazing boom of the 1980s and 90s, and most of them are quietly taking money off their owners every month in ways that never show up on any single bill.
We survey houses like this every week, so we've done these sums more times than we can count. What follows is what a tired set of uPVC windows really costs to keep, and the point where replacing them becomes the cheaper choice.
Cost 1: The energy penalty (the big one)
A uPVC window fitted in 1995 typically carries a whole-window U-value of around 2.8-3.2. A modern A++ window manages 1.2 or better, so the old one leaks more than twice the heat through every square metre of frame and glass. On a typical 3-bed semi with 15-18m² of glazing, that gap is worth roughly £150-£250 a year at 2026 energy prices. Most people nurse old windows along for another decade or so, and over those ten years that's £1,500-£2,500 handed to the energy company for nothing. Most of a replacement budget, in other words. If you want the physics behind it, our heat loss guide breaks it all down.
Cost 2: The repair treadmill
Windows fail in clusters, because everything was fitted on the same day and has aged at the same rate. Somewhere around the 20-25 year mark, the faults start turning up together:
- Misted sealed units at £80-£150 each to replace, and once one seal goes its neighbours tend to follow
- Perished gaskets and seals, £40-£80 per window
- Failed friction hinges, £50-£90 per window
- Worn locks, handles and gearboxes, £60-£120 each
Taken on its own, any one of these is a perfectly sensible repair. Our repair team does them every day, and where the frame is sound we'll always fix rather than replace. But when a whole house starts failing on schedule, £300-£500 a year in drip-fed repairs is common. That's money spent propping up windows that still carry the full energy penalty above.
Cost 3: Condensation, mould and redecorating
Cold glass breeds condensation, and condensation breeds mould. This cost hides in the decorating budget. Fungicidal washes. Stain-block. Repainting the reveals every couple of years, curtains and blinds written off, and in the worse cases plaster damage around the openings. In a badly affected home, £100-£300 a year is realistic, and that's before you count what damp air does to anyone in the house with asthma.
Cost 4: What buyers knock off the price
Viewers clock tired windows from the pavement, and surveyors flag them in the report. Estate agents around Manchester tell us the same thing over and over. Visibly old glazing invites offers below asking, because buyers price the replacement in, and they price it generously in their own favour. A £6,000 window job has a way of turning into a £10,000 negotiation discount. If a sale is anywhere in your future, spend ten minutes with the sums in our guide to whether new windows add value.
The five-year test
| Keeping old windows (typical, per year) | Cost |
|---|---|
| Extra energy vs modern glazing | £150-£250 |
| Repairs (units, hinges, locks, seals) | £100-£300 |
| Condensation damage and redecorating | £50-£150 |
| Total over 5 years | £1,500-£3,500 |
Now set that against replacement. A whole-house uPVC job on a Manchester semi typically runs £4,500-£8,000, comes with a 10-year guarantee, and switches off all three running costs on day one, while throwing in kerb appeal and better security for free. Keep the old windows another five years and you'll often spend half the price of new ones, with nothing to show for it at the end.
When keeping them is right
Sometimes it is, and we'll say so. If your windows are under 15 years old, still square in their openings and just need a couple of units or hinges, repair is the right call, whatever a commission-hungry salesman tells you. The tipping point comes past 20 years, when faults arrive in clusters and frames have yellowed or moved. Not sure which side of the line you're on? Our 10 signs checklist and a free survey will settle it. We make made-to-measure replacements in Trafford Park and repair across all of Greater Manchester, so we genuinely don't mind which answer suits your house.
How to replace without overspending
If the maths says replace, put the budget where it earns. Get quotes on a whole-house basis, because per-window pricing improves a lot at volume, but ask for a phased option too so you can compare fairly. Make sure A++ glazing and warm-edge spacers sit in the base spec rather than being dangled as an upsell, and steer any spare money towards the elevations that face the weather and the rooms you actually live in. Not the box room. Above all, buy from a fabricator rather than a sales-led national brand. Stripping out the commission layer typically saves 20-30% on identical or better specification, and if anything ever needs attention you'll be talking to the people who made your frames.
One more tip for Manchester in particular. Book outside the autumn rush. Every October, the first cold week reminds thousands of homeowners about their windows at exactly the same time, and lead times stretch. A survey in spring or summer gets you better availability and a calmer decision.
Frequently asked questions
How much do old windows add to energy bills?
Failed or pre-2002 double glazing typically loses two to three times the heat of a modern A++ window. For an average 3-bed semi that works out at £150-£250 a year at 2026 prices, and more in larger or all-electric homes.
Are 25-year-old uPVC windows worth repairing?
Usually only as a stopgap. By that age the plastic is often brittle, the seals have hardened and the hardware is obsolete, so each repair buys less time than the last. Structural faults such as cracked welds or warped frames can't be repaired at all.
Do old uPVC windows affect a house sale?
Yes, and out of proportion to their real cost. Surveyors flag failed units, and buyers negotiate off visibly tired glazing, often by more than replacement would have cost you. Fresh windows also lift the EPC, which buyers increasingly check.
Can I replace windows a few at a time?
Absolutely. Phased replacement, worst elevation first, is a sensible way to spread the budget. We quote whole-house and phased options side by side so you can see exactly what the difference is.
What do replacement uPVC windows cost in Manchester?
Typically £450-£900 per window fitted depending on size and spec, or £4,500-£8,000 for a typical 3-bed semi. Buying direct from a fabricator strips out the sales-commission layer that national brands build into their prices.
Is it worth replacing windows before winter?
Yes. The savings start with the heating season, and each opening is only exposed for under an hour, so cold-weather fitting isn't a problem. Just book early, because autumn is the industry's busiest period in the North West and lead times stretch from October onwards.
Want the real number for your house?
WhatsApp us a few photos or book a free survey. We'll tell you straight what's worth repairing, what's due for replacement, and what either route costs, with windows made in our own Manchester factory and a 10-year guarantee behind them.
Call 07533 830717, WhatsApp us a photo for a fast quote, or request a free quote online.