Does anyone know of a really effective product to clean the black streak marks from white upvc? The bars on my conservatory roof look awful and it's only a year old. My usual favourite, Jif cream, doesn't get the marks off and I also tried a specialist product from Kleeneze which didn't work at all.
Jif cream is abrasive - all you are doing is putting tiny scratches on the surface. You need a specialist cleaner and any Upvc supplier will sell you one. This will dissolve the marks. The marks actually sound like tar or the black rubber gunge they use to seal the windows - give whoever put the conservatory a call and tell them you are still waiting for them to finish the job
Thanks for the reply, Markandshez. Yes, you're right - Jif is abrasive. I'll look in the local ads for a upvc supplier and try to get some cleaner that way.