Came across this job today. Its a 12 year old metal roof, green in color. The house has an addition on the left hand side that shows the color of the roof and newer metal that is still the original color. The light, puke green color is oxidation. There is still plenty of good color left under the this, just need an effective and timely way to remove it.
I was considering a 20% mix of f-13 gutter grenade, then lots of rinsing with the booster pump. Anyone else have ideas or come across a situation like this before?
Ray, I had the same exact call here in central florida on a 4000sq ft 7 year old roof....same color. I tried test spots for the customer.....the F13 w/brushing did help but a light pressure washing no chems did the same with less time. Customer still did not like the results so we both agreed to pass on the cleaning.