If you live in a humid area surrounded by vegetation, you can confront with the appearance and development of algae, lichens and mold on the surface of the roof. They appear on most types of cover: bituminous, ceramic, stone etc., great for metal roofing this problem is not an issue.
Unfortunately, the formation and development of mold on the roof has a negative impact on the value of the house, due to the altered appearance of the cover. In some situations, mold stains are only an aesthetic problem, but they can also reflect other structural problems.
It is not difficult to identify the mold formation on the roof and, in most cases, simply removing it with adequate cleaning products prevents its recurrence. Fortunately, algae, lichens or mold removal from the roof is easy. DIY stores sell a wide variety of liquid biocide solutions specifically designed for such cleaning operations. However, biocides, chlorine and detergents are substances with a risk factor for the health of the vegetation around the house, so make sure to follow the manufacturers` indications to ensure adequate cleaning and protection at the same time.
Alternatively, you can prepare a safer mold repellent at home, using recipes based on water and liquid detergent or distillate vinegar, or hire a professional cleaner.