My garage roof has a lot of moss on one side of it, some of it in large 3-4" inch patches about 1/2"-1" thick. I just got an estimate to clean it for $500.
It seems they just spray the roof with a cleaning mixture and eventually the moss dies and blows off the roof.

I've watched some videos on you tube of just spraying it with a one-to-one water and heavy-duty bleach mixture from the ground or on a ladder against the side of the garage.
Has anyone tried this or have any other suggestions on how I might clean it without going up on the roof?
Thanks