If you look at your ceiling and think it is a bit worn, it may need a thorough cleaning. Sometimes algae and moss build-up on the roof can make shingles look worse than they actually are. A professional roofer can inspect your roof and discuss its condition with you. If they think cleaning is the best option, they can either do the job themselves or refer you to a reputable roof cleaning company.
If your roof needs to be replaced, your contractor may recommend shingles that contain copper or other materials that help repel algae growth. A roofer can also provide advice on how to keep the roof clean and how often to schedule cleanings.