Cloudy headlights: why they go yellow and how restoration works
Headlights go cloudy and yellow because the plastic lens loses its factory UV coating and the surface starts to break down in the sun; restoration sands off that damaged layer, polishes the lens clear and seals it with a new UV coat.
Why the plastic yellows
Most modern headlight lenses are plastic, not glass. From the factory they have a clear protective coating. Years of sun, heat and road grit wear that coating away, and the exposed plastic oxidises: first a haze, then a yellow, cloudy surface.
Why it matters
A cloudy lens lets less light through, so you see less at night and other drivers see you later. It also makes a car look older than it is.
How restoration works
The lens is wet sanded to take the damaged surface off, working through finer grades until it is even. Then it is polished until it is clear. The last step is the one that makes it last: a UV protective coat, which replaces the factory coating.
Polishing on its own, without a new coating, can look good for a while and then yellow again quickly.
At your home or work
A pair takes about 60 to 90 minutes where the car is parked, and it comes with a 12 month guarantee against going yellow again. You can see the price and book a time on the headlight restoration page, and add a windscreen chip repair in the same visit.
Signs your headlights need it
The first sign is a haze you only notice in some light. Then the lenses turn yellow or cloudy, sometimes with a rough feel when you run a finger over them. At night the beam looks weaker and more scattered. If one headlight looks clearer than the other, the cloudy one has usually lost more of its coating.
Restoration or new headlights
New headlight units fix it too, but they cost far more than a restoration, and on many cars they have to be ordered in. If the lens is only cloudy on the outside, restoration brings back most of the clarity at a fraction of the cost. It is not the answer if the lens is cracked, or if moisture has got inside the headlight: then a new unit is the fix.
Looking after them afterwards
Park in the shade when you can, wash the lenses with car shampoo rather than harsh cleaners, and do not scrub them with abrasive pads. The UV coat does the heavy lifting, and gentle care helps it last.
How long it takes, and what you need to do
A pair takes about 60 to 90 minutes, depending on how far the lenses have gone. I need the car parked where I can work at the front, out of direct rain. You do not need to be there for the whole job.
When I finish, the lenses are clear and sealed, and you can drive straight away. If you have a chip on the windscreen too, add it when you book and it is done in the same visit, for one trip.
Is it worth doing on an older car?
Often more than on a newer one. Older cars are the ones whose lenses have had the most sun, and a clear pair of headlights changes how the whole front of the car looks. If you are selling, clear headlights make the car look looked after in the photos. If you are keeping it, you get your night vision back for a fraction of the price of new units.
Questions
Do toothpaste and bug spray fixes work?
They can clear a light haze for a short time, but they do not replace the UV coating, so the yellowing comes back.
How long does a restoration last?
With a UV protective coat it lasts much longer than polishing alone. Mine comes with a 12 month guarantee against yellowing again.
Can you do one headlight?
Ask by text when you book; the online price is for the pair.