Went to home show over the weekend hoping to view some bathroom fixtures but all I got was contractors selling their services. One of them was for clearing moss and mold off roof. My roof does have moss on it so I got a quote. Now my question is - do I really need to worry @ the moss? The roof is @ 10 yrs old - only the one layer. When we replaced the roof the new shingles were supposedly moss resistant (I would have to check if there is a warranty @ the moss). Nothing is leaking of anything but parts of the roof definitely have moss. The area is shady and we're not planning to cut down all the trees so it will continue to be shady. So do I need to worry @ the moss impacting the durability or waterproofing of the roof?