What are the black streaks on my Coral Springs roof?
Those dark streaks are usually a type of algae that thrives in warm, humid places. In South Florida it spreads easily because of the heat, regular rain and long summers. The streaks start small, often on the shaded or north-facing slopes, and then grow into broad dark stripes.
Other growth you might see includes green mildew, moss and lichen, especially under trees. On concrete or barrel tile, the surface turns gray, dark or blotchy.
This is not just a looks issue. Algae holds moisture against the roof surface, and it can wear it down over time. Cleaning removes the growth, but it does not repair a failing roof. If tiles are cracked, slipped or missing, you need a roofer to look at it, not just a cleaning crew.
