Roof cleaning/moss

[alsander55]

I sure this has been covered before, But what's the best way to clean my 5 year old roof. I have alot of fir needles, cones and of course, moss.
Will light presure washing affect of hurt the shingles? Expert advice is greatly appreciated!

[joneq]

Came across this in my travels. Need adobe reader.

http://www.asphaltroofing.org/pdf/tb_217.pdf