How to Clean Mildew & Fungus Roof Stains
- 1). Fill the bucket with hot water, then add one cup of chlorine bleach. Be careful not to splash the bleach on your skin or clothing.
- 2). Dip a broom into the bucket of cleaner and whisk a generous amount onto the mildew and fungus stains, making sure you saturate the stains with cleaner. Let stand one half hour.
- 3). Repeat the wetting process, this time using the wet broom to sweep the mildew and fungus off the roof. The stains will be lifted and the fungus will roll off easily.
- 4). Rinse the roof with a garden hose, taking care to work from the top down to avoid spraying water up and under the shingles.
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