# Easily Cleaning Black Algae Stains Off a Roof



## roofrins (Jan 8, 2014)

*Black algae* can grow on the North faces of *roofs*, at least here in *Alabama* where I'm from. I've found that a product called "*Stain Solver*" does a great job of getting that stuff off. It's an oxygen bleach that's plant safe (produced by AskTheBuilder.com's *Tim Carter*). You simply mix it with hot water, spray it on, and rinse it off. It's still good to have a *pressure-washer* to rinse it off with (just works better), but you want to be careful not to get the tip close to the roof (like you would for a concrete driveway) because it will dislodge the granules and hurt the roof. For a before/after picture, check out* Pressure Washing Techniques*.​


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