How to Remove and Prevent Roof Moss

SOUTH SAN FRANCISCO — Does your roof have moss, algae or lichen growing on it? Here’s how to remove it and prevent it from reappearing:

Cleaning

Make a cleaning solution of bleach and water (if you want something more environmentally friendly, use potassium fatty acid in place of bleach). Spray the solution on your roof—this will kill the moss/algae/lichen growth. Do not attempt to power wash your roof or employ abrasive brushing, as these will do more harm than good. And remember: safety first. If you don’t feel comfortable getting up on your roof, call a licensed roofing professional to handle this job for you.

Prevention

Even if you completely remove fungal growth from your roof, if the conditions remain the same, it’ll soon return. A great way to prevent growth from reoccurring is to install a zinc strip at the ridgeline of your roof. This metal strip will naturally leach out electrons that eliminate moss, algae and lichen. Ideally, you would have the zinc strip installed when you replace your roof system.