Repair or Replace Your Windows? How to Decide

It's easy to assume a problem window needs replacing entirely, but that's rarely the cheapest or most sensible option. Here's how to think through the decision honestly, based on what we actually find when we inspect windows across London.

Start with the frame, not the symptom

The symptom you notice — misting, draughts, stiffness, a broken handle — is rarely the deciding factor on its own. What matters most is the condition of the frame itself. If the frame is sound, straight and free of rot or corrosion, almost every other fault is repairable.

Signs a repair is usually the right call

These are the situations where repair nearly always makes more sense than replacement.

Misted or cracked glass with an otherwise solid frame — just the unit needs swapping
Stiff, jammed or dropped sashes caused by worn hinges or hardware
A lock or handle that's failed but the door panel itself is undamaged
Draughts caused by worn seals rather than a warped frame
Timber that has some surface wear but no significant rot in structural sections

Signs replacement genuinely makes more sense

There are situations where repair would just be delaying the inevitable, and we'll tell you honestly if we think that's the case.

The frame itself is cracked, warped, or visibly out of square
Rusted internal reinforcement in a uPVC frame causing the frame to bow
Extensive rot through structural sections of a timber frame
Multiple compounding faults where the repair cost approaches replacement cost
You're planning wider changes (e.g. changing window style or improving thermal performance significantly)

A sensible way to approach it

Get the actual fault diagnosed rather than guessing from the symptom — a stiff window and a misted window can look similarly 'tired' but have completely different, and differently priced, fixes. We always inspect before quoting, and we'll say plainly if we think a repair isn't worth it for your specific window.

Want a professional to handle it?

Get a quote

Call Mark on 07535 916982 or request a callback.

Related repairs we handle

Covering Central London and out to the M25

Frequently asked questions

How do I know if my window frame is still sound?

Check for visible cracks, warping, or gaps where the frame meets the wall, and for uPVC, look for any bowing or discolouration that might suggest internal reinforcement has rusted. If in doubt, we can assess this for you on a callout.

Is it ever worth replacing just to improve energy efficiency?

Sometimes, especially with older single glazing or early double glazing with poor thermal performance — but upgrading the sealed unit within an existing sound frame can often achieve much of the improvement at a fraction of the cost.

Will you try to sell me a repair even if replacement is better value?

No — we're a repair-first company because most windows genuinely don't need full replacement, but we'll say clearly if we think your specific window has gone beyond a sensible repair.

Can you repair some windows in a property and replace others?

Yes — it's common for a property to have a mix, where some windows just need a unit or hardware repair and others (perhaps a very old, damaged frame) are better replaced.