The Roof Cleaning Institute Of America Training & Certification Forum
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I will tell if you if you change that avatar LOL. i am sorry man that is got to be the weirdest thing i have ever seen ( A Fly With a Run-ee noise)lol don't take me serious i am just messing with you. 
to answer your question you need  to paint a better picture of the roof you are describing.how old how steep,what color and so on...