So I’m out of fresh wash and my local pw store doesn’t have fresh wash or any thing equivalent . So on a recommendation of the owner I bought a 12.00$ gallon bottle of his favorite car wash. I had 2 houses to wash that day. I mixed in maybe 2 cups or less in a 5 gallon bucket with 4-5 gallons of SH and I down streamed it on to the houses. By the time I was done applying chemical to one wall I looked back and the mildew was devolving and running of the trim and siding. After only a couple minutes of dwelling I quickly rinsed it off and whala, it was squeaky clean! After telling a buddy of mine who is a car detailer told me he uses the same car wash when he washes cars. He to claims he has tried others and always gos back to this particular one. I wonder if it will work in a roof mix.