Originally Posted by rlitman
I used a tank sprayer with a nozzle like that to apply the oxy-clean to the roof. No ladders, no walking on the roof. Just spray the whole roof until everything was white and foamy, and let it soak in.
It's been a few weeks, and about half the moss has rolled off in this last rain. It is getting better every day.
But that was just 5 gallons of water to cover the whole roof of my 2 car garage.
I'd be wary about using even that sort of sprayer on a hose end. It may not be a pressure washer, but it will still remove more granules and shorten the roof's lifetime.
Sure, if that's what the customer insists on, and they need it looking clean and new now, what can you do? But they need to understand that anything more powerful than rain will cause deterioration (ok, not as much as the moss does itself, but it is still not a good thing).
I have done it many times on the end of a garden hose. House pressure 50 - 65 psi isn't as hard as a good thunderstorm.