Sweep off your roof. Use the broom to clear the roof of debris. You will likely dislodge some of the green stuff in the process.
Put on your safety gear. You should already be wearing slip-resistant shoes; put on gloves and goggles, too.
Mix your cleaning solution. In the pump sprayer, combine a gallon of water, a quart of bleach and 1/4 cup of TSP powder.
Wet the roof with the solution. Cover the roof with the cleaning solution using the pump sprayer. Work from top to bottom and left to right. Allow the solution to sit for no more than 15 minutes on the roof. If it sits longer, it can damage many types of shingles.
Rinse off the roof with the hose. Use the highest pressure that your garden hose can supply. If you notice any stubborn green stuff still hanging on, scrub it with the push broom until it disappears.
Things You Will Need
- Slip resistant shoes
- Safety goggles
- Rubber gloves
- Push broom
- Pump sprayer
- Trisodium Phosphate (TSP)
- Prevent recurrence of mold, mildew and algae by running a thin, copper strip under the top layer of shingles.
- Protect your landscaping from the diluted bleach runoff by spraying the plants down with water and covering them with plastic before you start working.