- 1). Prune off any branches that overhang the roof with a pole-handled pruning saw, especially on the north- and west-facing sides of the house. These are the areas that receive sun last and are most likely to grow algae. Removing branches will also keep air circulating, thus evaporating moisture from the roof.
- 2). Rent a pressure washer and connect it to an outdoor faucet. Put on a safety harness, tether, hard hat and shoes that have good traction. Lean a ladder against the eave of the house and get up on the roof. Once there, tether yourself to the building's chimney. Algae-covered roofs are often slippery and treacherous.
- 3). Turn on the washer and spray from the peak of the roof downward, washing algae into the gutters with water. Do not use chlorine or other toxic chemicals because they will kill grass and plants as the water drains off the roof. Let the pressure do the work.
- 4). Cut lengths of copper sheet with tin snips that are 6 inches wide and as long as the sheeting itself. Nail it lengthwise, 3 inches from the peak with roofing nails and a hammer. Fold the strips over the peak and nail them down on the other side. As rain runs off it will leach trace amounts of oxidizing copper onto the roofing material, poisoning any algae that remains and preventing it from returning.
SHARE
