[simonr]

pic is of glass in a factory roof,  they've tried pressure washing , it had hardly any affect they think its stained from the metal roof , would viroisol do anything to it

[Smurf]

That's why I don't get involved in those sorts of jobs as if I can't get them clean makes me look like a right plonker. 
For a start it don't look like glass too me.

pic is of glass in a factory roof,  they've tried pressure washing , it had hardly any affect they think its stained from the metal roof , would viroisol do anything to it

[Smurf]

Maybe phone this company up for advice?
http://www.pactek.co.uk/sky-light-cleaning.html

[simonr]

cheers i'll try them, it is glass though,  its my sons mate opening a gym in an old factory so its not dead important, i might give it a scrub with virosol anyway

[Matt.]

Simon, send me a text I have a pic for you

07968352201

[8weekly]

I'm with Smurf on this.

[Matt.]

I done these with virosol it's just finding the right chemical