DEAR TIM: Many roofs in my neighborhood, mine included, are covered with black streaks. What’s causing this to happen, and can the roofs be cleaned? I’m able to walk on my asphalt shingle roof with ...

QDEAR TIM: My roof needs cleaning. It's a newer asphalt shingle roof, but parts of it are covered with moss, lichens and algae. Is a pressure washer a good tool for cleaning roof shingles? Will it ...

Q: I have a newer asphalt shingle roof, but parts of it are covered with moss, lichens and algae. Is a pressure washer the best choice for cleaning roof shingles? Will it remove all of this growth?

Q - Our roof has dark streaks in various places even though there are no trees directly around our home; our neighbor says it needs to be cleaned. How would we clean the roof? The guy with his ...