We use a 5 5 gallon system just for this reason.
Osphate cleaning concentrates for metal roofs.
Tsp can be very difficult to mix hot water is recommended but not needed here is a simple method.
Mixing tsp for roof cleaning when mixing the tsp with bleach for roof cleaning you will want to use a pressure washer with the black soft spray chemical injector tip.
It certainly will deliver on its promise which is to eradicate any signs of mossy growth or dark streaks.
Spray this mixture onto the roof and agitate it with a soft bristled brush to get it clean.
Clean off the loose stuff use a pressure washer if you can paint this on and wait.
It s unreal how well this stuff works.
1 3 cup of powdered laundry detergent 1 quart of bleach 5 solution 3 quarts of water.
I shared my discovery with a friend and he pointed me to the data sheets for this and klean strip s phosphoric prep and etch product.
Some spots got cleaned so well i could see shiny bare metal.
Pine sap decaying leaves and even road dirt that s drifted into the air can settle on your metal roof and stain it.
All in all if you are dealing with metal surfaces roof asphalt or even tough fabric materials as such then 6071 jomax roof cleaner can be one of the best options for you.
Lightly scrub the surface until the area is free of mildew or mold.
Dip a soft brush or rag in the cleanser and apply to affected areas.