I have been asked to de-moss a roof. The angle of the roof is probably shallow enough that I could walk on it. I can borrow a roofing ladder. I was thinking of getting up there with a wire brush and simply brushing moss off and bagging it up. Any thought's guys? Would iy be better to pressure wash it off? I don't really fancy this way as I would rather do it by hand off a roofing ladder as I would feel this is the safer option.