How to Apply Metal Roof Cleaner
- 1). Mix 1/2 cup of TSP to 2 gallons of water in a large bucket. Mix 1/2 cup of chlorine bleach to the solution if the metal roof has mold or mildew present.
- 2). Pour a few ounces of the cleaning mixture onto a small section of the roof. Spread it evenly with a long-handled push broom and let it soak for 10 to 15 minutes.
- 3). Scrub with the broom to loosen any stuck-on dirt or residue. Rinse with a garden hose or power washer set at no higher than 1000 PSI (pounds per square inch). Continue this process across the entire roof.