You use very hot water and keep the roof wet until the stains disappear. Demo that I saw took most of the day.
If it dries you have to pressure washer it off.
__________________
Matthew C Perry General Manager Callahan Pro Wash Professional Exterior Cleaning Services Roof Cleaning, Pressure Washing, Paver Cleaning and Restoration 813-727-5161 callahanprowash.gmail.com
I will be glad to send you the "business in the box" from them It is brand new, used one time and lets just say "love" cleaned that mess up, Now I will just wait til "love" returns my lost money to my checkbook And I am sure it will, with the help all members of this forum provide. Thanks again for being here