Cracked Or Discoloured uPVC Frames
Yellowing is cosmetic and treatable; splits at the welded corners are structural and aren't.
Most people landing here want one thing: to decide between cleaning, spraying and replacing yellowed or split uPVC. That's what this page answers — no scare tactics, no automatic upsell to a full replacement.
What you'll notice first
- white frames gone yellow or grey, worst on the sunniest elevation
- a hairline split running diagonally from a welded corner
- the surface feeling chalky and marking your hand when you touch it
- beading that has gone brittle and cracks when it's unclipped
What actually causes it
- 1UV degradation of the surface layer over twenty-plus years
- 2abrasive cleaners taking the gloss layer off and exposing porous material underneath
- 3thermal cycling stressing welded corners on dark or south-facing frames
- 4thin early-generation profiles with less UV stabiliser than modern extrusions
Your realistic options
A proper uPVC restorer on chalky but sound frames brings a surprising amount back. Cheapest first move and it tells you whether the profile is genuinely finished.
A specialist two-pack coating can recolour sound frames — for example white to anthracite — at far less than replacement cost. It needs sound, crack-free profile to bond to.
The right answer when corners have split, the profile has gone brittle, or the frames are old enough that gaskets and beads are no longer available.
Discolouration alone is not a reason to replace windows, and we'll say that plainly even though replacement is what we sell. Cracking at the welds is different — that's the frame telling you it has lost its integrity, and no coating fixes it.
What we check on survey
- we test whether the discolouration lifts with a restorer before recommending anything
- we inspect every welded corner, inside and out, for hairline splits
- we flex the beading to see whether the plastic has gone brittle
- we check whether gaskets for that profile are still obtainable
How it's priced
Cleaning is a DIY afternoon. Spraying is priced by frame count and access. Replacement is per opening, and doing a whole elevation together is meaningfully cheaper per window than one at a time.
How urgent is it? Cosmetic issues can wait. Cracked welds shouldn't, because a split corner lets water into the reinforcement and the frame loses rigidity from the inside out.
Stopping it coming back
- never use abrasive pads or cream cleaners on uPVC — they strip the gloss layer permanently
- wash frames twice a year with warm soapy water, especially near roads
- keep planters and hoses off the cill where they trap moisture against the frame
Cracked Or Discoloured uPVC Frames — questions we get asked
Can yellowed uPVC be brought back to white?
Partly, with a dedicated restorer, if the degradation is surface-level. Deeply oxidised profile won't fully return and spraying is the better answer.
Is spraying uPVC frames any good?
Done properly on sound frames with a two-pack coating, yes — it lasts well and it's a fraction of replacement cost. On brittle or split profile it's money wasted.
Should I replace all the windows at once?
Not necessarily, but doing an elevation together costs less per opening and gives you a consistent finish, which matters visually more than people expect.
Does a cracked frame corner matter?
Yes. The weld is the structural joint. Once it opens, water reaches the steel reinforcement and the frame's rigidity goes.
If replacement is the answer
10-year product guarantee, 2-year fit warranty, lifetime hardware servicing
10-year product, 2-year fitting, lifetime hardware servicing
10-year product on every frame, 2-year fitting on the whole package, single point of contact
10-year powder-coat guarantee, 2-year fit warranty
Cracked Or Discoloured uPVC Frames in your town
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