[JackieW]

Cleaned a lean to glass roof recently using Virosol first, followed by pure water. Got rid of the algae and cleaned the glass but the tops have lots of stains on the top 8-12 inches that looks like they've run down from the lead flashing.

A quick search on this site hasn't really come up with a definite answer as to how to remove these.

I'd like to spray something on and then water off.

Any suggestions or answers?

Thanks

[rosskesava]

If the lead stains have been there a while, there's not much that can be done.

If I remember rightly, that stain is lead carbonate which is a hard as hell and once it's on the glass for any period of time.......

[dd]

Not much point cleaning the marks as they will re-appear shortly with more rain.

[sunshine windows]

Crystal clear's Winsol 500 will remove hardened limescale marks and lead stains no problem