What percentage of window jobs are repairs, honestly?

At the honest end of the trade, the large majority of call-outs are repairs or unit swaps. Replacement is the right answer maybe one time in five, warped frames, house-wide end-of-life, or deliberate upgrade.

How long should uPVC windows last?

Frames: 25–35 years for decent profiles. Sealed units: 15–25. Hardware: 10–15. The layers fail at different rates, which is exactly why repair-first works.

Will new windows add value to my house?

Fresh A-rated windows help saleability and EPC scores, but rarely return their full cost pound-for-pound. Replace for condition, comfort and bills, not as a value play.

Repair or replace? Deciding honestly

Repair when frames are square, sound and draught-free, hardware and glass problems cost £60–£150 to fix and frames last decades. Replace when frames have warped, seals and gaskets have failed house-wide, or you're upgrading for efficiency or looks. The £60–£120 repair and the £500 replacement often solve the same symptom.

The window industry makes its real money on replacement, so the default advice homeowners hear is often "new windows". The truth is more useful: most window problems are component failures in frames with decades left in them. This guide is the decision framework the honest end of the trade actually uses.

Problems that are almost always repairs (£60–£150)

Misted units, the glass has failed, not the window. Unit swap, £80–£150.
Jammed, stiff or broken handles, £60–£90, part included.
Windows that won't lock, espagnolette gearbox, £80–£120.
Draughts, gaskets, hinges or a dropped sash, £60–£120.
Dropped sashes catching the frame, realignment and new hinges, £70–£120.
Door alignment and multipoint locks, £70–£150 against £1,000+ for a new door.

The rule: if the frame is sound, everything attached to it is replaceable at repair prices.

Signs that genuinely point to replacement (£400–£700 per window)

Warped or racked frames, sashes that can't be aligned because the frame has moved. Common on very early uPVC and sun-baked south elevations.
Perished everything, gaskets crumbling, hardware obsolete, seals failed across multiple windows at once. The system, not the components, is done.
Repeated unit failures on the same frames, usually frame drainage or movement killing each new unit within a few years.
Single glazing or failed early double glazing house-wide, the efficiency gap is now large enough that modern A-rated units pay back meaningfully.
You want the change, colours, styles, bays, bigger glass. A legitimate reason; just know it's a want, not a need, and price it as such.

The middle case: units plus hardware refresh

The most under-used option on Teesside: keep sound frames, replace all the sealed units with modern low-e argon glass, and refresh hinges, handles and gaskets in the same programme. Roughly £1,200–£2,000 for a typical semi, half the price of full replacement, with most of the thermal benefit. Ask about it when you get quotes; not every firm volunteers it because the margin lives elsewhere.

The questions that sort honest quotes from upsells

Ask anyone quoting replacement: "What's actually failed that a repair won't fix?" and "What would a units-and-hardware refresh cost on these frames?" Honest specialists answer both happily. The ones who can't explain why repair won't work are selling, not surveying.

Getting both prices

The cleanest way through the decision is to hold both numbers at once. Describe the symptoms in the quote form and ask for repair and replacement pricing where relevant, up to 5 Trusted local specialists, usually within 24 hours.