We have two “stains” on our roof from where we had our TV antenna. The antenna was removed about a year ago. Is there any way to remove these stains?
A TV antenna can cause two types of “stains.” Both types of stains will not damage a typical asphalt shingle roof, and don’t need to be removed. They may be ugly, but it’s not a serious maintenance issue.
A rusty colored, black stain is from rusting metal on the antenna or the fasteners. This type of stain will lighten with time as the weather and sun bleaches out the color. You could try a rust removal chemical like Whink Rust and Iron Stain Remover, but I suggest waiting for the stain to disappear.
The other type of “stain” may be a lack of fungus growing below the metal of the antenna. The zinc coating on the metal becomes an oxide with rainwater, and as it runs down the roof, it stops algae growth. If the stain is a light color, the rest of the roof has algae. The algae can be removed with Jomax or a similar product.
I don’t suggest a homeowner should attempt to clean a roof – it’s just too dangerous. A dry roof is dangerous enough. Adding cleaning solutions, water, and chemicals can make a roof slippery and even more dangerous. Leave the cleaning to professionals.