While having your roof cleaned isn't an everyday task, it is certainly a necessary one. Getting your shingle roof soft washed has a multitude of benefits. Including: getting rid of unsightly stains, keeping growth from occurring causing premature wear, even maintaining the warranty of a newly installed roof. Soft washing is the way to go.
Ah yes, the metal roof. One of the most attractive items that can be purchased for your home. It is also one of the biggest investments you can make. Maintain the longevity of your metal roof by having it cleaned. Removing those hideous black streaks actually keeps your roof cooler, allowing the panel to breathe and doesn't store moisture on the roofs surface which could lead to premature paint or galvanized coating failure and even rust that can compromise the roofs structural integrity.
Revolutionary War financier and Innovator Robert Morris, was one of the first to install sheet iron on his Philadelphia mansion in 1794.
Another advocate for the "tin-plate" roof was Thomas Jefferson. Having installed such a roof on Monticello, his home in Albemarle County, Virginia.
Although I bet theirs won't be as clean as yours!